java/15 : java.desktop/com/sun/imageio/plugins/tiff/TIFFDecompressor.java

TIFFDecompressor
https://openjdk.java.net/
GPLv2 + Classpath Exception
/*
 * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.sun.imageio.plugins.tiff;

import java.awt.Rectangle;
import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.ComponentColorModel;
import java.awt.image.ComponentSampleModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.DataBufferDouble;
import java.awt.image.DataBufferFloat;
import java.awt.image.DataBufferInt;
import java.awt.image.DataBufferShort;
import java.awt.image.DataBufferUShort;
import java.awt.image.MultiPixelPackedSampleModel;
import java.awt.image.PixelInterleavedSampleModel;
import java.awt.image.Raster;
import java.awt.image.SampleModel;
import java.awt.image.SinglePixelPackedSampleModel;
import java.awt.image.WritableRaster;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.nio.ByteOrder;
import javax.imageio.IIOException;
import javax.imageio.ImageReader;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.MemoryCacheImageInputStream;
import javax.imageio.plugins.tiff.BaselineTIFFTagSet;
import com.sun.imageio.plugins.common.ImageUtil;
import com.sun.imageio.plugins.common.BogusColorSpace;
import com.sun.imageio.plugins.common.SimpleCMYKColorSpace;

A class defining a pluggable TIFF decompressor.
 The mapping between source and destination Y coordinates is
given by the equations:
dx = (sx - sourceXOffset)/subsampleX + dstXOffset;
dy = (sy - sourceYOffset)/subsampleY + dstYOffset;

Note that the mapping from source coordinates to destination
coordinates is not one-to-one if subsampling is being used, since
only certain source pixels are to be copied to the
destination. However, * the inverse mapping is always one-to-one:
sx = (dx - dstXOffset)*subsampleX + sourceXOffset;
sy = (dy - dstYOffset)*subsampleY + sourceYOffset;

 Decompressors may be written with various levels of complexity. The most complex decompressors will override the decode method, and will perform all the work of decoding, subsampling, offsetting, clipping, and format conversion. This approach may be the most efficient, since it is possible to avoid the use of extra image buffers, and it may be possible to avoid decoding portions of the image that will not be copied into the destination. 
 Less ambitious decompressors may override the decodeRaw method, which is responsible for decompressing the entire tile or strip into a byte array (or other appropriate datatype). The default implementation of decode will perform all necessary setup of buffers, call decodeRaw to perform the actual decoding, perform subsampling, and copy the results into the final destination image. Where possible, it will pass the real image buffer to decodeRaw in order to avoid making an extra copy. 
 Slightly more ambitious decompressors may override decodeRaw, but avoid writing pixels that will be discarded in the subsampling phase. /**
 * A class defining a pluggable TIFF decompressor.
 *
 * <p> The mapping between source and destination Y coordinates is
 * given by the equations:
 *
 * <pre>
 * dx = (sx - sourceXOffset)/subsampleX + dstXOffset;
 * dy = (sy - sourceYOffset)/subsampleY + dstYOffset;
 * </pre>
 *
 * Note that the mapping from source coordinates to destination
 * coordinates is not one-to-one if subsampling is being used, since
 * only certain source pixels are to be copied to the
 * destination. However, * the inverse mapping is always one-to-one:
 *
 * <pre>
 * sx = (dx - dstXOffset)*subsampleX + sourceXOffset;
 * sy = (dy - dstYOffset)*subsampleY + sourceYOffset;
 * </pre>
 *
 * <p> Decompressors may be written with various levels of complexity.
 * The most complex decompressors will override the
 * {@code decode} method, and will perform all the work of
 * decoding, subsampling, offsetting, clipping, and format conversion.
 * This approach may be the most efficient, since it is possible to
 * avoid the use of extra image buffers, and it may be possible to
 * avoid decoding portions of the image that will not be copied into
 * the destination.
 *
 * <p> Less ambitious decompressors may override the
 * {@code decodeRaw} method, which is responsible for
 * decompressing the entire tile or strip into a byte array (or other
 * appropriate datatype).  The default implementation of
 * {@code decode} will perform all necessary setup of buffers,
 * call {@code decodeRaw} to perform the actual decoding, perform
 * subsampling, and copy the results into the final destination image.
 * Where possible, it will pass the real image buffer to
 * {@code decodeRaw} in order to avoid making an extra copy.
 *
 * <p> Slightly more ambitious decompressors may override
 * {@code decodeRaw}, but avoid writing pixels that will be
 * discarded in the subsampling phase.
 */
public abstract class TIFFDecompressor {

    The ImageReader calling this TIFFDecompressor. /**
     * The {@code ImageReader} calling this
     * {@code TIFFDecompressor}.
     */
    protected ImageReader reader;

    The IIOMetadata object containing metadata for the current image. /**
     * The {@code IIOMetadata} object containing metadata for the
     * current image.
     */
    protected IIOMetadata metadata;

    The value of the PhotometricInterpretation tag. Legal values are BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_WHITE_IS_ZERO, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_BLACK_IS_ZERO, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_RGB, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_PALETTE_COLOR, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_TRANSPARENCY_MASK, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_Y_CB_CR, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_CIELAB, BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_ICCLAB, or other value defined by a TIFF extension. /**
     * The value of the {@code PhotometricInterpretation} tag.
     * Legal values are {@link
     * BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_WHITE_IS_ZERO },
     * {@link
     * BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_BLACK_IS_ZERO},
     * {@link BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_RGB},
     * {@link
     * BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_PALETTE_COLOR},
     * {@link
     * BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_TRANSPARENCY_MASK},
     * {@link BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_Y_CB_CR},
     * {@link BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_CIELAB},
     * {@link BaselineTIFFTagSet#PHOTOMETRIC_INTERPRETATION_ICCLAB},
     * or other value defined by a TIFF extension.
     */
    protected int photometricInterpretation;

    The value of the Compression tag. Legal values are BaselineTIFFTagSet.COMPRESSION_NONE, BaselineTIFFTagSet.COMPRESSION_CCITT_RLE, BaselineTIFFTagSet.COMPRESSION_CCITT_T_4, BaselineTIFFTagSet.COMPRESSION_CCITT_T_6, BaselineTIFFTagSet.COMPRESSION_LZW, BaselineTIFFTagSet.COMPRESSION_OLD_JPEG, BaselineTIFFTagSet.COMPRESSION_JPEG, BaselineTIFFTagSet.COMPRESSION_ZLIB, BaselineTIFFTagSet.COMPRESSION_PACKBITS, BaselineTIFFTagSet.COMPRESSION_DEFLATE, or other value defined by a TIFF extension. /**
     * The value of the {@code Compression} tag. Legal values are
     * {@link BaselineTIFFTagSet#COMPRESSION_NONE}, {@link
     * BaselineTIFFTagSet#COMPRESSION_CCITT_RLE}, {@link
     * BaselineTIFFTagSet#COMPRESSION_CCITT_T_4}, {@link
     * BaselineTIFFTagSet#COMPRESSION_CCITT_T_6}, {@link
     * BaselineTIFFTagSet#COMPRESSION_LZW}, {@link
     * BaselineTIFFTagSet#COMPRESSION_OLD_JPEG}, {@link
     * BaselineTIFFTagSet#COMPRESSION_JPEG}, {@link
     * BaselineTIFFTagSet#COMPRESSION_ZLIB}, {@link
     * BaselineTIFFTagSet#COMPRESSION_PACKBITS}, {@link
     * BaselineTIFFTagSet#COMPRESSION_DEFLATE}, or other value
     * defined by a TIFF extension.
     */
    protected int compression;

    true if the image is encoded using separate planes. /**
     * {@code true} if the image is encoded using separate planes.
     */
    protected boolean planar;

    The planar band to decode; ignored for chunky (interleaved) images.
/**
     * The planar band to decode; ignored for chunky (interleaved) images.
     */
    protected int planarBand = 0;

    The value of the SamplesPerPixel tag. /**
     * The value of the {@code SamplesPerPixel} tag.
     */
    protected int samplesPerPixel;

    The value of the BitsPerSample tag. /**
     * The value of the {@code BitsPerSample} tag.
     *
     */
    protected int[] bitsPerSample;

    The value of the SampleFormat tag. Legal values are BaselineTIFFTagSet.SAMPLE_FORMAT_UNSIGNED_INTEGER, BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER, BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT, BaselineTIFFTagSet.SAMPLE_FORMAT_UNDEFINED, or other value defined by a TIFF extension. /**
     * The value of the {@code SampleFormat} tag.  Legal values
     * are {@link BaselineTIFFTagSet#SAMPLE_FORMAT_UNSIGNED_INTEGER},
     * {@link BaselineTIFFTagSet#SAMPLE_FORMAT_SIGNED_INTEGER}, {@link
     * BaselineTIFFTagSet#SAMPLE_FORMAT_FLOATING_POINT}, {@link
     * BaselineTIFFTagSet#SAMPLE_FORMAT_UNDEFINED}, or other value
     * defined by a TIFF extension.
     */
    protected int[] sampleFormat =
        new int[] {BaselineTIFFTagSet.SAMPLE_FORMAT_UNSIGNED_INTEGER};

    The value of the ExtraSamples tag. Legal values are BaselineTIFFTagSet.EXTRA_SAMPLES_UNSPECIFIED, BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA, BaselineTIFFTagSet.EXTRA_SAMPLES_UNASSOCIATED_ALPHA, or other value defined by a TIFF extension. /**
     * The value of the {@code ExtraSamples} tag.  Legal values
     * are {@link BaselineTIFFTagSet#EXTRA_SAMPLES_UNSPECIFIED},
     * {@link BaselineTIFFTagSet#EXTRA_SAMPLES_ASSOCIATED_ALPHA},
     * {@link BaselineTIFFTagSet#EXTRA_SAMPLES_UNASSOCIATED_ALPHA},
     * or other value defined by a TIFF extension.
     */
    protected int[] extraSamples;

    The value of the ColorMap tag. /**
     * The value of the {@code ColorMap} tag.
     *
     */
    protected char[] colorMap;

    // Region of input stream containing the data

    The ImageInputStream containing the TIFF source data. /**
     * The {@code ImageInputStream} containing the TIFF source
     * data.
     */
    protected ImageInputStream stream;

    The offset in the source ImageInputStream of the start of the data to be decompressed. /**
     * The offset in the source {@code ImageInputStream} of the
     * start of the data to be decompressed.
     */
    protected long offset;

    The number of bytes of data from the source ImageInputStream to be decompressed. /**
     * The number of bytes of data from the source
     * {@code ImageInputStream} to be decompressed.
     */
    protected int byteCount;

    // Region of the file image represented in the stream
    // This is unaffected by subsampling

    The X coordinate of the upper-left pixel of the source region
being decoded from the source stream.  This value is not affected
by source subsampling.
/**
     * The X coordinate of the upper-left pixel of the source region
     * being decoded from the source stream.  This value is not affected
     * by source subsampling.
     */
    protected int srcMinX;

    The Y coordinate of the upper-left pixel of the source region
being decoded from the source stream.  This value is not affected
by source subsampling.
/**
     * The Y coordinate of the upper-left pixel of the source region
     * being decoded from the source stream.  This value is not affected
     * by source subsampling.
     */
    protected int srcMinY;

    The width of the source region being decoded from the source
stream.  This value is not affected by source subsampling.
/**
     * The width of the source region being decoded from the source
     * stream.  This value is not affected by source subsampling.
     */
    protected int srcWidth;

    The height of the source region being decoded from the source
stream.  This value is not affected by source subsampling.
/**
     * The height of the source region being decoded from the source
     * stream.  This value is not affected by source subsampling.
     */
    protected int srcHeight;

    // Subsampling to be performed

    The source X offset used, along with dstXOffset and subsampleX, to map between horizontal source and destination pixel coordinates. /**
     * The source X offset used, along with {@code dstXOffset}
     * and {@code subsampleX}, to map between horizontal source
     * and destination pixel coordinates.
     */
    protected int sourceXOffset;

    The horizontal destination offset used, along with sourceXOffset and subsampleX, to map between horizontal source and destination pixel coordinates. See the comment for sourceXOffset for the mapping equations. /**
     * The horizontal destination offset used, along with
     * {@code sourceXOffset} and {@code subsampleX}, to map
     * between horizontal source and destination pixel coordinates.
     * See the comment for {@link #sourceXOffset sourceXOffset} for
     * the mapping equations.
     */
    protected int dstXOffset;

    The source Y offset used, along with dstYOffset and subsampleY, to map between vertical source and destination pixel coordinates. /**
     * The source Y offset used, along with {@code dstYOffset}
     * and {@code subsampleY}, to map between vertical source and
     * destination pixel coordinates.
     */
    protected int sourceYOffset;

    The vertical destination offset used, along with sourceYOffset and subsampleY, to map between horizontal source and destination pixel coordinates. See the comment for sourceYOffset for the mapping equations. /**
     * The vertical destination offset used, along with
     * {@code sourceYOffset} and {@code subsampleY}, to map
     * between horizontal source and destination pixel coordinates.
     * See the comment for {@link #sourceYOffset sourceYOffset} for
     * the mapping equations.
     */
    protected int dstYOffset;

    The horizontal subsampling factor.  A factor of 1 means that
every column is copied to the destination; a factor of 2 means
that every second column is copied, etc.
/**
     * The horizontal subsampling factor.  A factor of 1 means that
     * every column is copied to the destination; a factor of 2 means
     * that every second column is copied, etc.
     */
    protected int subsampleX;

    The vertical subsampling factor.  A factor of 1 means that
every row is copied to the destination; a factor of 2 means
that every second row is copied, etc.
/**
     * The vertical subsampling factor.  A factor of 1 means that
     * every row is copied to the destination; a factor of 2 means
     * that every second row is copied, etc.
     */
    protected int subsampleY;

    // Band subsetting/rearrangement

    The sequence of source bands that are to be copied into the
destination.
/**
     * The sequence of source bands that are to be copied into the
     * destination.
     */
    protected int[] sourceBands;

    The sequence of destination bands to receive the source data.
/**
     * The sequence of destination bands to receive the source data.
     */
    protected int[] destinationBands;

    // Destination for decodeRaw

    A BufferedImage for the decodeRaw method to write into. /**
     * A {@code BufferedImage} for the {@code decodeRaw}
     * method to write into.
     */
    protected BufferedImage rawImage;

    // Destination

    The final destination image.
/**
     * The final destination image.
     */
    protected BufferedImage image;

    The X coordinate of the upper left pixel to be written in the
destination image.
/**
     * The X coordinate of the upper left pixel to be written in the
     * destination image.
     */
    protected int dstMinX;

    The Y coordinate of the upper left pixel to be written in the
destination image.
/**
     * The Y coordinate of the upper left pixel to be written in the
     * destination image.
     */
    protected int dstMinY;

    The width of the region of the destination image to be written.
/**
     * The width of the region of the destination image to be written.
     */
    protected int dstWidth;

    The height of the region of the destination image to be written.
/**
     * The height of the region of the destination image to be written.
     */
    protected int dstHeight;

    // Region of source contributing to the destination

    The X coordinate of the upper-left source pixel that will actually be copied into the destination image, taking into account all subsampling, offsetting, and clipping. That is, the pixel at (activeSrcMinX, activeSrcMinY) is to be copied into the destination pixel at (dstMinX, dstMinY).  The pixels in the source region to be copied are those with X coordinates of the form activeSrcMinX +
k*subsampleX, where k is an integer such that 0 <= k < dstWidth. /**
     * The X coordinate of the upper-left source pixel that will
     * actually be copied into the destination image, taking into
     * account all subsampling, offsetting, and clipping.  That is,
     * the pixel at ({@code activeSrcMinX},
     * {@code activeSrcMinY}) is to be copied into the
     * destination pixel at ({@code dstMinX},
     * {@code dstMinY}).
     *
     * <p> The pixels in the source region to be copied are
     * those with X coordinates of the form {@code activeSrcMinX +
     * k*subsampleX}, where {@code k} is an integer such
     * that {@code 0 <= k < dstWidth}.
     */
    protected int activeSrcMinX;

    The Y coordinate of the upper-left source pixel that will
actually be copied into the destination image, taking into account
all subsampling, offsetting, and clipping.
 The pixels in the source region to be copied are those with Y coordinates of the form activeSrcMinY +
k*subsampleY, where k is an integer such that 0 <= k < dstHeight. /**
     * The Y coordinate of the upper-left source pixel that will
     * actually be copied into the destination image, taking into account
     * all subsampling, offsetting, and clipping.
     *
     * <p> The pixels in the source region to be copied are
     * those with Y coordinates of the form {@code activeSrcMinY +
     * k*subsampleY}, where {@code k} is an integer such
     * that {@code 0 <= k < dstHeight}.
     */
    protected int activeSrcMinY;

    The width of the source region that will actually be copied
into the destination image, taking into account all
susbampling, offsetting, and clipping.
 The active source width will always be equal to (dstWidth - 1)*subsampleX + 1. /**
     * The width of the source region that will actually be copied
     * into the destination image, taking into account all
     * susbampling, offsetting, and clipping.
     *
     * <p> The active source width will always be equal to
     * {@code (dstWidth - 1)*subsampleX + 1}.
     */
    protected int activeSrcWidth;

    The height of the source region that will actually be copied
into the destination image, taking into account all
susbampling, offsetting, and clipping.
 The active source height will always be equal to (dstHeight - 1)*subsampleY + 1. /**
     * The height of the source region that will actually be copied
     * into the destination image, taking into account all
     * susbampling, offsetting, and clipping.
     *
     * <p> The active source height will always be equal to
     * {@code (dstHeight - 1)*subsampleY + 1}.
     */
    protected int activeSrcHeight;

    A TIFFColorConverter object describing the color space of the encoded pixel data, or null. /**
     * A {@code TIFFColorConverter} object describing the color space of
     * the encoded pixel data, or {@code null}.
     */
    protected TIFFColorConverter colorConverter;

    private boolean isBilevel;
    private boolean isContiguous;
    private boolean isImageSimple;
    private boolean adjustBitDepths;
    private int[][] bitDepthScale;

    // source pixel at (sx, sy) should map to dst pixel (dx, dy), where:
    //
    // dx = (sx - sourceXOffset)/subsampleX + dstXOffset;
    // dy = (sy - sourceYOffset)/subsampleY + dstYOffset;
    //
    // Note that this mapping is many-to-one.  Source pixels such that
    // (sx - sourceXOffset) % subsampleX != 0 should not be copied
    // (and similarly for y).
    //
    // The backwards mapping from dest to source is one-to-one:
    //
    // sx = (dx - dstXOffset)*subsampleX + sourceXOffset;
    // sy = (dy - dstYOffset)*subsampleY + sourceYOffset;
    //
    // The reader will always hand us the full source region as it
    // exists in the file.  It will take care of clipping the dest region
    // to exactly those dest pixels that are present in the source region.

    Create a PixelInterleavedSampleModel for use in creating an ImageTypeSpecifier. Its dimensions will be 1x1 and it will have ascending band offsets as {0, 1, 2, ..., numBands}. 
Params: dataType – The data type (DataBuffer.TYPE_*).
numBands – The number of bands.
Returns: A PixelInterleavedSampleModel./**
     * Create a {@code PixelInterleavedSampleModel} for use in creating
     * an {@code ImageTypeSpecifier}.  Its dimensions will be 1x1 and
     * it will have ascending band offsets as {0, 1, 2, ..., numBands}.
     *
     * @param dataType The data type (DataBuffer.TYPE_*).
     * @param numBands The number of bands.
     * @return A {@code PixelInterleavedSampleModel}.
     */
    static SampleModel createInterleavedSM(int dataType,
                                           int numBands) {
        int[] bandOffsets = new int[numBands];
        for(int i = 0; i < numBands; i++) {
            bandOffsets[i] = i;
        }
        return new PixelInterleavedSampleModel(dataType,
                                               1, // width
                                               1, // height
                                               numBands, // pixelStride,
                                               numBands, // scanlineStride
                                               bandOffsets);
    }

    Create a ComponentColorModel for use in creating an ImageTypeSpecifier. /**
     * Create a {@code ComponentColorModel} for use in creating
     * an {@code ImageTypeSpecifier}.
     */
    // This code was inspired by the method of the same name in
    // javax.imageio.ImageTypeSpecifier
    static ColorModel createComponentCM(ColorSpace colorSpace,
                                        int numBands,
                                        int[] bitsPerSample,
                                        int dataType,
                                        boolean hasAlpha,
                                        boolean isAlphaPremultiplied) {
        int transparency =
            hasAlpha ? Transparency.TRANSLUCENT : Transparency.OPAQUE;

        return new ComponentColorModel(colorSpace,
                                       bitsPerSample,
                                       hasAlpha,
                                       isAlphaPremultiplied,
                                       transparency,
                                       dataType);
    }

    private static int createMask(int[] bitsPerSample, int band) {
        int mask = (1 << bitsPerSample[band]) - 1;
        for (int i = band + 1; i < bitsPerSample.length; i++) {
            mask <<= bitsPerSample[i];
        }

        return mask;
    }

    private static int getDataTypeFromNumBits(int numBits, boolean isSigned) {
        int dataType;

        if (numBits <= 8) {
            dataType = DataBuffer.TYPE_BYTE;
        } else if (numBits <= 16) {
            dataType = isSigned ?
                DataBuffer.TYPE_SHORT : DataBuffer.TYPE_USHORT;
        } else {
            dataType = DataBuffer.TYPE_INT;
        }

        return dataType;
    }

    private static boolean areIntArraysEqual(int[] a, int[] b) {
        if(a == null || b == null) {
            if(a == null && b == null) {
                return true;
            } else { // one is null and one is not
                return false;
            }
        }

        if(a.length != b.length) {
            return false;
        }

        int length = a.length;
        for(int i = 0; i < length; i++) {
            if(a[i] != b[i]) {
                return false;
            }
        }

        return true;
    }

    Return the number of bits occupied by dataType which must be one of the DataBuffer TYPEs. /**
     * Return the number of bits occupied by {@code dataType}
     * which must be one of the {@code DataBuffer} {@code TYPE}s.
     */
    private static int getDataTypeSize(int dataType) throws IIOException {
        int dataTypeSize = 0;
        switch(dataType) {
        case DataBuffer.TYPE_BYTE:
            dataTypeSize = 8;
            break;
        case DataBuffer.TYPE_SHORT:
        case DataBuffer.TYPE_USHORT:
            dataTypeSize = 16;
            break;
        case DataBuffer.TYPE_INT:
        case DataBuffer.TYPE_FLOAT:
            dataTypeSize = 32;
            break;
        case DataBuffer.TYPE_DOUBLE:
            dataTypeSize = 64;
            break;
        default:
            throw new IIOException("Unknown data type "+dataType);
        }

        return dataTypeSize;
    }

    Returns the number of bits per pixel.
/**
     * Returns the number of bits per pixel.
     */
    private static int getBitsPerPixel(SampleModel sm) {
        int bitsPerPixel = 0;
        int[] sampleSize = sm.getSampleSize();
        int numBands = sampleSize.length;
        for(int i = 0; i < numBands; i++) {
            bitsPerPixel += sampleSize[i];
        }
        return bitsPerPixel;
    }

    Returns whether all samples have the same number of bits.
/**
     * Returns whether all samples have the same number of bits.
     */
    private static boolean areSampleSizesEqual(SampleModel sm) {
        boolean allSameSize = true;
        int[] sampleSize = sm.getSampleSize();
        int sampleSize0 = sampleSize[0];
        int numBands = sampleSize.length;

        for(int i = 1; i < numBands; i++) {
            if(sampleSize[i] != sampleSize0) {
                allSameSize = false;
                break;
            }
        }

        return allSameSize;
    }

    Determines whether the DataBuffer is filled without any interspersed padding bits. /**
     * Determines whether the {@code DataBuffer} is filled without
     * any interspersed padding bits.
     */
    private static boolean isDataBufferBitContiguous(SampleModel sm,
        int[] bitsPerSample)
        throws IIOException {
        int dataTypeSize = getDataTypeSize(sm.getDataType());

        if(sm instanceof ComponentSampleModel) {
            int numBands = sm.getNumBands();
            for(int i = 0; i < numBands; i++) {
                if(bitsPerSample[i] != dataTypeSize) {
                    // Sample does not fill data element.
                    return false;
                }
            }
        } else if(sm instanceof MultiPixelPackedSampleModel) {
            MultiPixelPackedSampleModel mppsm =
                (MultiPixelPackedSampleModel)sm;
            if(dataTypeSize % mppsm.getPixelBitStride() != 0) {
                // Pixels do not fill the data element.
                return false;
            }
        } else if(sm instanceof SinglePixelPackedSampleModel) {
            SinglePixelPackedSampleModel sppsm =
                (SinglePixelPackedSampleModel)sm;
            int numBands = sm.getNumBands();
            int numBits = 0;
            for(int i = 0; i < numBands; i++) {
                numBits += sm.getSampleSize(i);
            }
            if(numBits != dataTypeSize) {
                // Pixel does not fill the data element.
                return false;
            }
        } else {
            // Unknown SampleModel class.
            return false;
        }

        return true;
    }

    Reformats data read as bytes into a short or int buffer.
/**
     * Reformats data read as bytes into a short or int buffer.
     */
    private static void reformatData(byte[] buf,
                                     int bytesPerRow,
                                     int numRows,
                                     short[] shortData,
                                     int[] intData,
                                     int outOffset,
                                     int outStride)
        throws IIOException {

        if(shortData != null) {
            int inOffset = 0;
            int shortsPerRow = bytesPerRow/2;
            int numExtraBytes = bytesPerRow % 2;
            for(int j = 0; j < numRows; j++) {
                int k = outOffset;
                for(int i = 0; i < shortsPerRow; i++) {
                    shortData[k++] =
                        (short)(((buf[inOffset++]&0xff) << 8) |
                                (buf[inOffset++]&0xff));
                }
                if(numExtraBytes != 0) {
                    shortData[k++] = (short)((buf[inOffset++]&0xff) << 8);
                }
                outOffset += outStride;
            }
        } else if(intData != null) {
            int inOffset = 0;
            int intsPerRow = bytesPerRow/4;
            int numExtraBytes = bytesPerRow % 4;
            for(int j = 0; j < numRows; j++) {
                int k = outOffset;
                for(int i = 0; i < intsPerRow; i++) {
                    intData[k++] =
                        ((buf[inOffset++]&0xff) << 24) |
                        ((buf[inOffset++]&0xff) << 16) |
                        ((buf[inOffset++]&0xff) << 8) |
                        (buf[inOffset++]&0xff);
                }
                if(numExtraBytes != 0) {
                    int shift = 24;
                    int ival = 0;
                    for(int b = 0; b < numExtraBytes; b++) {
                        ival |= (buf[inOffset++]&0xff) << shift;
                        shift -= 8;
                    }
                    intData[k++] = ival;
                }
                outOffset += outStride;
            }
        } else {
            throw new IIOException("shortData == null && intData == null!");
        }
    }

    Reformats bit-discontiguous data into the DataBuffer of the supplied WritableRaster. /**
     * Reformats bit-discontiguous data into the {@code DataBuffer}
     * of the supplied {@code WritableRaster}.
     */
    private static void reformatDiscontiguousData(byte[] buf,
                                                  int[] bitsPerSample,
                                                  int stride,
                                                  int w,
                                                  int h,
                                                  WritableRaster raster)
        throws IOException {

        // Get SampleModel info.
        SampleModel sm = raster.getSampleModel();
        int numBands = sm.getNumBands();

        // Initialize input stream.
        ByteArrayInputStream is = new ByteArrayInputStream(buf);
        ImageInputStream iis = new MemoryCacheImageInputStream(is);

        // Reformat.
        long iisPosition = 0L;
        int y = raster.getMinY();
        for(int j = 0; j < h; j++, y++) {
            iis.seek(iisPosition);
            int x = raster.getMinX();
            for(int i = 0; i < w; i++, x++) {
                for(int b = 0; b < numBands; b++) {
                    long bits = iis.readBits(bitsPerSample[b]);
                    raster.setSample(x, y, b, (int)bits);
                }
            }
            iisPosition += stride;
        }
    }

    A utility method that returns an ImageTypeSpecifier suitable for decoding an image with the given parameters. 
Params: photometricInterpretation – the value of the PhotometricInterpretation field.
compression – the value of the Compression field.
samplesPerPixel – the value of the SamplesPerPixel field.
bitsPerSample – the value of the BitsPerSample field.
sampleFormat – the value of the SampleFormat field.
extraSamples – the value of the ExtraSamples field.
colorMap – the value of the ColorMap field.
Returns: a suitable ImageTypeSpecifier, or null if it is not possible to create one./**
     * A utility method that returns an
     * {@code ImageTypeSpecifier} suitable for decoding an image
     * with the given parameters.
     *
     * @param photometricInterpretation the value of the
     * {@code PhotometricInterpretation} field.
     * @param compression the value of the {@code Compression} field.
     * @param samplesPerPixel the value of the
     * {@code SamplesPerPixel} field.
     * @param bitsPerSample the value of the {@code BitsPerSample} field.
     * @param sampleFormat the value of the {@code SampleFormat} field.
     * @param extraSamples the value of the {@code ExtraSamples} field.
     * @param colorMap the value of the {@code ColorMap} field.
     *
     * @return a suitable {@code ImageTypeSpecifier}, or
     * {@code null} if it is not possible to create one.
     */
    public static ImageTypeSpecifier
        getRawImageTypeSpecifier(int photometricInterpretation,
                                 int compression,
                                 int samplesPerPixel,
                                 int[] bitsPerSample,
                                 int[] sampleFormat,
                                 int[] extraSamples,
                                 char[] colorMap) {

        //
        // Types to support:
        //
        // 1, 2, 4, 8, or 16 bit grayscale or indexed
        // 8,8-bit gray+alpha
        // 16,16-bit gray+alpha
        // 8,8,8-bit RGB
        // 8,8,8,8-bit RGB+alpha
        // 16,16,16-bit RGB
        // 16,16,16,16-bit RGB+alpha
        // R+G+B = 8-bit RGB
        // R+G+B+A = 8-bit RGB
        // R+G+B = 16-bit RGB
        // R+G+B+A = 16-bit RGB
        // 8X-bits/sample, arbitrary numBands.
        // Arbitrary non-indexed, non-float layouts (discontiguous).
        //

        // Band-sequential

        // 1, 2, 4, 8, or 16 bit grayscale or indexed images
        if (samplesPerPixel == 1 &&
            (bitsPerSample[0] == 1 ||
             bitsPerSample[0] == 2 ||
             bitsPerSample[0] == 4 ||
             bitsPerSample[0] == 8 ||
             bitsPerSample[0] == 16)) {

            // 2 and 16 bits images are not in the baseline
            // specification, but we will allow them anyway
            // since they fit well into Java2D
            //
            // this raises the issue of how to write such images...

            if (colorMap == null) {
                // Grayscale
                boolean isSigned = (sampleFormat[0] ==
                              BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER);
                int dataType;
                if (bitsPerSample[0] <= 8) {
                    dataType = DataBuffer.TYPE_BYTE;
                } else {
                    dataType = sampleFormat[0] ==
                        BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER ?
                        DataBuffer.TYPE_SHORT :
                        DataBuffer.TYPE_USHORT;
                }

                return ImageTypeSpecifier.createGrayscale(bitsPerSample[0],
                                                          dataType,
                                                          isSigned);
            } else {
                // Indexed
                int mapSize = 1 << bitsPerSample[0];
                byte[] redLut = new byte[mapSize];
                byte[] greenLut = new byte[mapSize];
                byte[] blueLut = new byte[mapSize];
                byte[] alphaLut = null;

                int idx = 0;
                for (int i = 0; i < mapSize; i++) {
                    redLut[i] = (byte)((colorMap[i]*255)/65535);
                    greenLut[i] = (byte)((colorMap[mapSize + i]*255)/65535);
                    blueLut[i] = (byte)((colorMap[2*mapSize + i]*255)/65535);
                }

                int dataType;
                if (bitsPerSample[0] <= 8) {
                    dataType = DataBuffer.TYPE_BYTE;
                } else if (sampleFormat[0] ==
                    BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER) {
                    dataType = DataBuffer.TYPE_SHORT;
                } else {
                    dataType = DataBuffer.TYPE_USHORT;
                }
                return ImageTypeSpecifier.createIndexed(redLut,
                                                        greenLut,
                                                        blueLut,
                                                        alphaLut,
                                                        bitsPerSample[0],
                                                        dataType);
            }
        }

        // 8-bit gray-alpha
        if (samplesPerPixel == 2 &&
            bitsPerSample[0] == 8 &&
            bitsPerSample[1] == 8) {
            int dataType = DataBuffer.TYPE_BYTE;
            boolean alphaPremultiplied = false;
            if (extraSamples != null &&
                extraSamples[0] ==
                BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                alphaPremultiplied = true;
            }
            return ImageTypeSpecifier.createGrayscale(8,
                                                      dataType,
                                                      false,
                                                      alphaPremultiplied);
        }

        // 16-bit gray-alpha
        if (samplesPerPixel == 2 &&
            bitsPerSample[0] == 16 &&
            bitsPerSample[1] == 16) {
            int dataType = sampleFormat[0] ==
                BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER ?
                DataBuffer.TYPE_SHORT :
                DataBuffer.TYPE_USHORT;
            boolean alphaPremultiplied = false;
            if (extraSamples != null &&
                extraSamples[0] ==
                BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                alphaPremultiplied = true;
            }
            boolean isSigned = dataType == DataBuffer.TYPE_SHORT;
            return ImageTypeSpecifier.createGrayscale(16,
                                                      dataType,
                                                      isSigned,
                                                      alphaPremultiplied);
        }

        ColorSpace rgb = ColorSpace.getInstance(ColorSpace.CS_sRGB);

        // 8-bit RGB
        if (samplesPerPixel == 3 &&
            bitsPerSample[0] == 8 &&
            bitsPerSample[1] == 8 &&
            bitsPerSample[2] == 8) {
            int[] bandOffsets = new int[3];
            bandOffsets[0] = 0;
            bandOffsets[1] = 1;
            bandOffsets[2] = 2;
            int dataType = DataBuffer.TYPE_BYTE;
            ColorSpace theColorSpace;
            if((photometricInterpretation ==
                BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_Y_CB_CR &&
                compression != BaselineTIFFTagSet.COMPRESSION_JPEG &&
                compression != BaselineTIFFTagSet.COMPRESSION_OLD_JPEG) ||
               photometricInterpretation ==
               BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_CIELAB) {
                theColorSpace =
                    ColorSpace.getInstance(ColorSpace.CS_LINEAR_RGB);
            } else {
                theColorSpace = rgb;
            }
            return ImageTypeSpecifier.createInterleaved(theColorSpace,
                                                        bandOffsets,
                                                        dataType,
                                                        false,
                                                        false);
        }

        // 8-bit RGBA
        if (samplesPerPixel == 4 &&
            bitsPerSample[0] == 8 &&
            bitsPerSample[1] == 8 &&
            bitsPerSample[2] == 8 &&
            bitsPerSample[3] == 8) {
            int[] bandOffsets = new int[4];
            bandOffsets[0] = 0;
            bandOffsets[1] = 1;
            bandOffsets[2] = 2;
            bandOffsets[3] = 3;
            int dataType = DataBuffer.TYPE_BYTE;

            ColorSpace theColorSpace;
            boolean hasAlpha;
            boolean alphaPremultiplied = false;
            if(photometricInterpretation ==
               BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_CMYK) {
                theColorSpace = SimpleCMYKColorSpace.getInstance();
                hasAlpha = false;
            } else {
                theColorSpace = rgb;
                hasAlpha = true;
                if (extraSamples != null &&
                    extraSamples[0] ==
                    BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                    alphaPremultiplied = true;
                }
            }

            return ImageTypeSpecifier.createInterleaved(theColorSpace,
                                                        bandOffsets,
                                                        dataType,
                                                        hasAlpha,
                                                        alphaPremultiplied);
        }

        // 16-bit RGB
        if (samplesPerPixel == 3 &&
            bitsPerSample[0] == 16 &&
            bitsPerSample[1] == 16 &&
            bitsPerSample[2] == 16) {
            int[] bandOffsets = new int[3];
            bandOffsets[0] = 0;
            bandOffsets[1] = 1;
            bandOffsets[2] = 2;
            int dataType = sampleFormat[0] ==
                BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER ?
                DataBuffer.TYPE_SHORT :
                DataBuffer.TYPE_USHORT;
            return ImageTypeSpecifier.createInterleaved(rgb,
                                                        bandOffsets,
                                                        dataType,
                                                        false,
                                                        false);
        }

        // 16-bit RGBA
        if (samplesPerPixel == 4 &&
            bitsPerSample[0] == 16 &&
            bitsPerSample[1] == 16 &&
            bitsPerSample[2] == 16 &&
            bitsPerSample[3] == 16) {
            int[] bandOffsets = new int[4];
            bandOffsets[0] = 0;
            bandOffsets[1] = 1;
            bandOffsets[2] = 2;
            bandOffsets[3] = 3;
            int dataType = sampleFormat[0] ==
                BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER ?
                DataBuffer.TYPE_SHORT :
                DataBuffer.TYPE_USHORT;

            boolean alphaPremultiplied = false;
            if (extraSamples != null &&
                extraSamples[0] ==
                BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                alphaPremultiplied = true;
            }
            return ImageTypeSpecifier.createInterleaved(rgb,
                                                        bandOffsets,
                                                        dataType,
                                                        true,
                                                        alphaPremultiplied);
        }

        // Compute bits per pixel.
        int totalBits = 0;
        for (int i = 0; i < bitsPerSample.length; i++) {
            totalBits += bitsPerSample[i];
        }

        // Packed: 3- or 4-band, 8- or 16-bit.
        if ((samplesPerPixel == 3 || samplesPerPixel == 4) &&
            (totalBits == 8 || totalBits == 16)) {
            int redMask = createMask(bitsPerSample, 0);
            int greenMask = createMask(bitsPerSample, 1);
            int blueMask = createMask(bitsPerSample, 2);
            int alphaMask = (samplesPerPixel == 4) ?
                createMask(bitsPerSample, 3) : 0;
            int transferType = totalBits == 8 ?
                DataBuffer.TYPE_BYTE : DataBuffer.TYPE_USHORT;
            boolean alphaPremultiplied = false;
            if (extraSamples != null &&
                extraSamples[0] ==
                BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                alphaPremultiplied = true;
            }
            return ImageTypeSpecifier.createPacked(rgb,
                                                   redMask,
                                                   greenMask,
                                                   blueMask,
                                                   alphaMask,
                                                   transferType,
                                                   alphaPremultiplied);
        }

        // Generic components with 8X bits per sample.
        if(bitsPerSample[0] % 8 == 0) {
            // Check whether all bands have same bit depth.
            boolean allSameBitDepth = true;
            for(int i = 1; i < bitsPerSample.length; i++) {
                if(bitsPerSample[i] != bitsPerSample[i-1]) {
                    allSameBitDepth = false;
                    break;
                }
            }

            // Proceed if all bands have same bit depth.
            if(allSameBitDepth) {
                // Determine the data type.
                int dataType = -1;
                boolean isDataTypeSet = false;
                switch(bitsPerSample[0]) {
                case 8:
                    if(sampleFormat[0] !=
                       BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {
                        // Ignore whether signed or unsigned:
                        // treat all as unsigned.
                        dataType = DataBuffer.TYPE_BYTE;
                        isDataTypeSet = true;
                    }
                    break;
                case 16:
                    if(sampleFormat[0] !=
                       BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {
                        if(sampleFormat[0] ==
                           BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER) {
                            dataType = DataBuffer.TYPE_SHORT;
                        } else {
                            dataType = DataBuffer.TYPE_USHORT;
                        }
                        isDataTypeSet = true;
                    }
                    break;
                case 32:
                    if(sampleFormat[0] ==
                       BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {
                        dataType = DataBuffer.TYPE_FLOAT;
                    } else {
                        dataType = DataBuffer.TYPE_INT;
                    }
                    isDataTypeSet = true;
                    break;
                case 64:
                    if(sampleFormat[0] ==
                       BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {
                        dataType = DataBuffer.TYPE_DOUBLE;
                        isDataTypeSet = true;
                    }
                    break;
                }

                if(isDataTypeSet) {
                    // Create the SampleModel.
                    SampleModel sm = createInterleavedSM(dataType,
                                                         samplesPerPixel);

                    // Create the ColorModel.
                    ColorModel cm;
                    if(samplesPerPixel >= 1 && samplesPerPixel <= 4 &&
                       (dataType == DataBuffer.TYPE_INT ||
                        dataType == DataBuffer.TYPE_FLOAT)) {
                        // Handle the 32-bit cases for 1-4 bands.
                        ColorSpace cs = samplesPerPixel <= 2 ?
                            ColorSpace.getInstance(ColorSpace.CS_GRAY) : rgb;
                        boolean hasAlpha = ((samplesPerPixel % 2) == 0);
                        boolean alphaPremultiplied = false;
                        if(hasAlpha && extraSamples != null &&
                           extraSamples[0] ==
                           BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                            alphaPremultiplied = true;
                        }

                        cm = createComponentCM(cs,
                                               samplesPerPixel,
                                               bitsPerSample,
                                               dataType,
                                               hasAlpha,
                                               alphaPremultiplied);
                    } else {
                        ColorSpace cs = new BogusColorSpace(samplesPerPixel);
                        cm = createComponentCM(cs,
                                               samplesPerPixel,
                                               bitsPerSample,
                                               dataType,
                                               false, // hasAlpha
                                               false); // alphaPremultiplied
                    }
                    return new ImageTypeSpecifier(cm, sm);
                }
            }
        }

        // Other more bizarre cases including discontiguous DataBuffers
        // such as for the image in bug 4918959.

        if(colorMap == null &&
           sampleFormat[0] !=
           BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {

            // Determine size of largest sample.
            int maxBitsPerSample = 0;
            for(int i = 0; i < bitsPerSample.length; i++) {
                if(bitsPerSample[i] > maxBitsPerSample) {
                    maxBitsPerSample = bitsPerSample[i];
                }
            }

            // Determine whether data are signed.
            boolean isSigned =
                (sampleFormat[0] ==
                 BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER);

            // Grayscale
            if(samplesPerPixel == 1 &&
                (bitsPerSample[0] == 1 || bitsPerSample[0] == 2 ||
                 bitsPerSample[0] == 4 || bitsPerSample[0] == 8 ||
                 bitsPerSample[0] == 16)) {
                int dataType = getDataTypeFromNumBits(maxBitsPerSample, isSigned);

                return ImageTypeSpecifier.createGrayscale(bitsPerSample[0],
                                                          dataType,
                                                          isSigned);
            }

            // Gray-alpha
            if (samplesPerPixel == 2 &&
                bitsPerSample[0] == bitsPerSample[1] &&
                (bitsPerSample[0] == 1 || bitsPerSample[0] == 2 ||
                 bitsPerSample[0] == 4 || bitsPerSample[0] == 8 ||
                 bitsPerSample[0] == 16)) {
                boolean alphaPremultiplied = false;
                if (extraSamples != null &&
                    extraSamples[0] ==
                    BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                    alphaPremultiplied = true;
                }

                int dataType =
                    getDataTypeFromNumBits(maxBitsPerSample, isSigned);

                return ImageTypeSpecifier.createGrayscale(maxBitsPerSample,
                                                          dataType,
                                                          false,
                                                          alphaPremultiplied);
            }

            if (samplesPerPixel == 3 || samplesPerPixel == 4) {
                int dataType = getDataTypeFromNumBits(maxBitsPerSample, isSigned);
                int dataTypeSize;
                try {
                    dataTypeSize = getDataTypeSize(dataType);
                } catch (IIOException ignored) {
                    dataTypeSize = maxBitsPerSample;
                }
                if(totalBits <= 32 && !isSigned) {
                    // Packed RGB or RGBA
                    int redMask = createMask(bitsPerSample, 0);
                    int greenMask = createMask(bitsPerSample, 1);
                    int blueMask = createMask(bitsPerSample, 2);
                    int alphaMask = (samplesPerPixel == 4) ?
                        createMask(bitsPerSample, 3) : 0;
                    int transferType =
                        getDataTypeFromNumBits(totalBits, false);
                    boolean alphaPremultiplied = false;
                    if (extraSamples != null &&
                        extraSamples[0] ==
                        BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                        alphaPremultiplied = true;
                    }
                    return ImageTypeSpecifier.createPacked(rgb,
                                                           redMask,
                                                           greenMask,
                                                           blueMask,
                                                           alphaMask,
                                                           transferType,
                                                           alphaPremultiplied);
                } else if(samplesPerPixel == 3 &&
                    dataTypeSize == bitsPerSample[0] &&
                    bitsPerSample[0] == bitsPerSample[1] &&
                    bitsPerSample[1] == bitsPerSample[2]) {
                    // Interleaved RGB
                    int[] bandOffsets = new int[] {0, 1, 2};
                    return ImageTypeSpecifier.createInterleaved(rgb,
                                                                bandOffsets,
                                                                dataType,
                                                                false,
                                                                false);
                } else if(samplesPerPixel == 4 &&
                    dataTypeSize == bitsPerSample[0] &&
                    bitsPerSample[0] == bitsPerSample[1] &&
                    bitsPerSample[1] == bitsPerSample[2] &&
                    bitsPerSample[2] == bitsPerSample[3]) {
                    // Interleaved RGBA
                    int[] bandOffsets = new int[] {0, 1, 2, 3};
                    boolean alphaPremultiplied = false;
                    if (extraSamples != null &&
                        extraSamples[0] ==
                        BaselineTIFFTagSet.EXTRA_SAMPLES_ASSOCIATED_ALPHA) {
                        alphaPremultiplied = true;
                    }
                    return ImageTypeSpecifier.createInterleaved(rgb,
                                                                bandOffsets,
                                                                dataType,
                                                                true,
                                                                alphaPremultiplied);
                }
            }

            // Arbitrary Interleaved.
            int dataType =
                getDataTypeFromNumBits(maxBitsPerSample, isSigned);
            SampleModel sm = createInterleavedSM(dataType,
                                                 samplesPerPixel);
            ColorSpace cs;
            if (samplesPerPixel <= 2) {
                cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
            } else if (samplesPerPixel <= 4) {
                cs = rgb;
            } else {
                cs = new BogusColorSpace(samplesPerPixel);
            }
            ColorModel cm = createComponentCM(cs,
                                              samplesPerPixel,
                                              bitsPerSample,
                                              dataType,
                                              false, // hasAlpha
                                              false); // alphaPremultiplied
            return new ImageTypeSpecifier(cm, sm);
        }

        return null;
    }

    Sets the value of the reader field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: reader – the current ImageReader./**
     * Sets the value of the {@code reader} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param reader the current {@code ImageReader}.
     */
    public void setReader(ImageReader reader) {
        this.reader = reader;
    }

    Sets the value of the metadata field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: metadata – the IIOMetadata object for the image being read./**
     * Sets the value of the {@code metadata} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param metadata the {@code IIOMetadata} object for the
     * image being read.
     */
    public void setMetadata(IIOMetadata metadata) {
        this.metadata = metadata;
    }

    Sets the value of the photometricInterpretation field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: photometricInterpretation – the photometric interpretation
value./**
     * Sets the value of the {@code photometricInterpretation}
     * field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param photometricInterpretation the photometric interpretation
     * value.
     */
    public void setPhotometricInterpretation(int photometricInterpretation) {
        this.photometricInterpretation = photometricInterpretation;
    }

    Sets the value of the compression field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: compression – the compression type./**
     * Sets the value of the {@code compression} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param compression the compression type.
     */
    public void setCompression(int compression) {
        this.compression = compression;
    }

    Sets the value of the planar field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: planar – true if the image to be decoded is stored in planar format./**
     * Sets the value of the {@code planar} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param planar {@code true} if the image to be decoded is
     * stored in planar format.
     */
    public void setPlanar(boolean planar) {
        this.planar = planar;
    }

    Sets the index of the planar configuration band to be decoded. This value
is ignored for chunky (interleaved) images.
Params: planarBand – the index of the planar band to decode/**
     * Sets the index of the planar configuration band to be decoded. This value
     * is ignored for chunky (interleaved) images.
     *
     * @param planarBand the index of the planar band to decode
     */
    public void setPlanarBand(int planarBand) { this.planarBand = planarBand; }

    Sets the value of the samplesPerPixel field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: samplesPerPixel – the number of samples in each source
pixel./**
     * Sets the value of the {@code samplesPerPixel} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param samplesPerPixel the number of samples in each source
     * pixel.
     */
    public void setSamplesPerPixel(int samplesPerPixel) {
        this.samplesPerPixel = samplesPerPixel;
    }

    Sets the value of the bitsPerSample field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: bitsPerSample – the number of bits for each source image
sample./**
     * Sets the value of the {@code bitsPerSample} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param bitsPerSample the number of bits for each source image
     * sample.
     */
    public void setBitsPerSample(int[] bitsPerSample) {
        this.bitsPerSample = bitsPerSample == null ?
            null : bitsPerSample.clone();
    }

    Sets the value of the sampleFormat field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: sampleFormat – the format of the source image data,
for example unsigned integer or floating-point./**
     * Sets the value of the {@code sampleFormat} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param sampleFormat the format of the source image data,
     * for example unsigned integer or floating-point.
     */
    public void setSampleFormat(int[] sampleFormat) {
        this.sampleFormat = sampleFormat == null ?
            new int[] {BaselineTIFFTagSet.SAMPLE_FORMAT_UNSIGNED_INTEGER} :
            sampleFormat.clone();
    }

    Sets the value of the extraSamples field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: extraSamples – the interpretation of any samples in the
source file beyond those used for basic color or grayscale
information./**
     * Sets the value of the {@code extraSamples} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param extraSamples the interpretation of any samples in the
     * source file beyond those used for basic color or grayscale
     * information.
     */
    public void setExtraSamples(int[] extraSamples) {
        this.extraSamples = extraSamples == null ?
            null : extraSamples.clone();
    }

    Sets the value of the colorMap field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: colorMap – the color map to apply to the source data, as an array of chars./**
     * Sets the value of the {@code colorMap} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param colorMap the color map to apply to the source data,
     * as an array of {@code char}s.
     */
    public void setColorMap(char[] colorMap) {
        this.colorMap = colorMap == null ?
            null : colorMap.clone();
    }

    Sets the value of the stream field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: stream – the ImageInputStream to be read./**
     * Sets the value of the {@code stream} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param stream the {@code ImageInputStream} to be read.
     */
    public void setStream(ImageInputStream stream) {
        this.stream = stream;
    }

    Sets the value of the offset field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: offset – the offset of the beginning of the compressed
data./**
     * Sets the value of the {@code offset} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param offset the offset of the beginning of the compressed
     * data.
     */
    public void setOffset(long offset) {
        this.offset = offset;
    }

    Sets the value of the byteCount field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: byteCount – the number of bytes of compressed data./**
     * Sets the value of the {@code byteCount} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param byteCount the number of bytes of compressed data.
     */
    public void setByteCount(int byteCount) {
        this.byteCount = byteCount;
    }

    // Region of the file image represented in the stream

    Sets the value of the srcMinX field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: srcMinX – the minimum X coordinate of the source region
being decoded, irrespective of how it will be copied into the
destination./**
     * Sets the value of the {@code srcMinX} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param srcMinX the minimum X coordinate of the source region
     * being decoded, irrespective of how it will be copied into the
     * destination.
     */
    public void setSrcMinX(int srcMinX) {
        this.srcMinX = srcMinX;
    }

    Sets the value of the srcMinY field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: srcMinY – the minimum Y coordinate of the source region
being decoded, irrespective of how it will be copied into the
destination./**
     * Sets the value of the {@code srcMinY} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param srcMinY the minimum Y coordinate of the source region
     * being decoded, irrespective of how it will be copied into the
     * destination.
     */
    public void setSrcMinY(int srcMinY) {
        this.srcMinY = srcMinY;
    }

    Sets the value of the srcWidth field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: srcWidth – the width of the source region being decoded,
irrespective of how it will be copied into the destination./**
     * Sets the value of the {@code srcWidth} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param srcWidth the width of the source region being decoded,
     * irrespective of how it will be copied into the destination.
     */
    public void setSrcWidth(int srcWidth) {
        this.srcWidth = srcWidth;
    }

    Sets the value of the srcHeight field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: srcHeight – the height of the source region being decoded,
irrespective of how it will be copied into the destination./**
     * Sets the value of the {@code srcHeight} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param srcHeight the height of the source region being decoded,
     * irrespective of how it will be copied into the destination.
     */
    public void setSrcHeight(int srcHeight) {
        this.srcHeight = srcHeight;
    }

    // First source pixel to be read

    Sets the value of the sourceXOffset field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: sourceXOffset – the horizontal source offset to be used when
mapping between source and destination coordinates./**
     * Sets the value of the {@code sourceXOffset} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param sourceXOffset the horizontal source offset to be used when
     * mapping between source and destination coordinates.
     */
    public void setSourceXOffset(int sourceXOffset) {
        this.sourceXOffset = sourceXOffset;
    }

    Sets the value of the dstXOffset field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstXOffset – the horizontal destination offset to be
used when mapping between source and destination coordinates./**
     * Sets the value of the {@code dstXOffset} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstXOffset the horizontal destination offset to be
     * used when mapping between source and destination coordinates.
     */
    public void setDstXOffset(int dstXOffset) {
        this.dstXOffset = dstXOffset;
    }

    Sets the value of the sourceYOffset.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: sourceYOffset – the vertical source offset to be used when
mapping between source and destination coordinates./**
     * Sets the value of the {@code sourceYOffset}.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param sourceYOffset the vertical source offset to be used when
     * mapping between source and destination coordinates.
     */
    public void setSourceYOffset(int sourceYOffset) {
        this.sourceYOffset = sourceYOffset;
    }

    Sets the value of the dstYOffset field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstYOffset – the vertical destination offset to be
used when mapping between source and destination coordinates./**
     * Sets the value of the {@code dstYOffset} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstYOffset the vertical destination offset to be
     * used when mapping between source and destination coordinates.
     */
    public void setDstYOffset(int dstYOffset) {
        this.dstYOffset = dstYOffset;
    }

    // Subsampling to be performed

    Sets the value of the subsampleX field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: subsampleX – the horizontal subsampling factor.
Throws: IllegalArgumentException – if subsampleX is less than or equal to 0./**
     * Sets the value of the {@code subsampleX} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param subsampleX the horizontal subsampling factor.
     *
     * @throws IllegalArgumentException if {@code subsampleX} is
     * less than or equal to 0.
     */
    public void setSubsampleX(int subsampleX) {
        if (subsampleX <= 0) {
            throw new IllegalArgumentException("subsampleX <= 0!");
        }
        this.subsampleX = subsampleX;
    }

    Sets the value of the subsampleY field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: subsampleY – the vertical subsampling factor.
Throws: IllegalArgumentException – if subsampleY is less than or equal to 0./**
     * Sets the value of the {@code subsampleY} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param subsampleY the vertical subsampling factor.
     *
     * @throws IllegalArgumentException if {@code subsampleY} is
     * less than or equal to 0.
     */
    public void setSubsampleY(int subsampleY) {
        if (subsampleY <= 0) {
            throw new IllegalArgumentException("subsampleY <= 0!");
        }
        this.subsampleY = subsampleY;
    }

    // Band subsetting/rearrangement

    Sets the value of the sourceBands field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: sourceBands – an array of ints specifying the source bands to be read./**
     * Sets the value of the {@code sourceBands} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param sourceBands an array of {@code int}s
     * specifying the source bands to be read.
     */
    public void setSourceBands(int[] sourceBands) {
        this.sourceBands = sourceBands == null ?
            null : sourceBands.clone();
    }

    Sets the value of the destinationBands field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: destinationBands – an array of ints specifying the destination bands to be written./**
     * Sets the value of the {@code destinationBands} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param destinationBands an array of {@code int}s
     * specifying the destination bands to be written.
     */
    public void setDestinationBands(int[] destinationBands) {
        this.destinationBands = destinationBands == null ?
            null : destinationBands.clone();
    }

    // Destination image and region

    Sets the value of the image field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: image – the destination BufferedImage./**
     * Sets the value of the {@code image} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param image the destination {@code BufferedImage}.
     */
    public void setImage(BufferedImage image) {
        this.image = image;
    }

    Sets the value of the dstMinX field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstMinX – the minimum X coordinate of the destination
region./**
     * Sets the value of the {@code dstMinX} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstMinX the minimum X coordinate of the destination
     * region.
     */
    public void setDstMinX(int dstMinX) {
        this.dstMinX = dstMinX;
    }

    Sets the value of the dstMinY field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstMinY – the minimum Y coordinate of the destination
region./**
     * Sets the value of the {@code dstMinY} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstMinY the minimum Y coordinate of the destination
     * region.
     */
    public void setDstMinY(int dstMinY) {
        this.dstMinY = dstMinY;
    }

    Sets the value of the dstWidth field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstWidth – the width of the destination region./**
     * Sets the value of the {@code dstWidth} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstWidth the width of the destination region.
     */
    public void setDstWidth(int dstWidth) {
        this.dstWidth = dstWidth;
    }

    Sets the value of the dstHeight field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: dstHeight – the height of the destination region./**
     * Sets the value of the {@code dstHeight} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param dstHeight the height of the destination region.
     */
    public void setDstHeight(int dstHeight) {
        this.dstHeight = dstHeight;
    }

    // Active source region

    Sets the value of the activeSrcMinX field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: activeSrcMinX – the minimum X coordinate of the active
source region./**
     * Sets the value of the {@code activeSrcMinX} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param activeSrcMinX the minimum X coordinate of the active
     * source region.
     */
    public void setActiveSrcMinX(int activeSrcMinX) {
        this.activeSrcMinX = activeSrcMinX;
    }

    Sets the value of the activeSrcMinY field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: activeSrcMinY – the minimum Y coordinate of the active
source region./**
     * Sets the value of the {@code activeSrcMinY} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param activeSrcMinY the minimum Y coordinate of the active
     * source region.
     */
    public void setActiveSrcMinY(int activeSrcMinY) {
        this.activeSrcMinY = activeSrcMinY;
    }

    Sets the value of the activeSrcWidth field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: activeSrcWidth – the width of the active source region./**
     * Sets the value of the {@code activeSrcWidth} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param activeSrcWidth the width of the active source region.
     */
    public void setActiveSrcWidth(int activeSrcWidth) {
        this.activeSrcWidth = activeSrcWidth;
    }

    Sets the value of the activeSrcHeight field.  If this method is called, the beginDecoding method must be called prior to calling any of the decode methods. 
Params: activeSrcHeight – the height of the active source region./**
     * Sets the value of the {@code activeSrcHeight} field.
     *
     * <p> If this method is called, the {@code beginDecoding}
     * method must be called prior to calling any of the decode
     * methods.
     *
     * @param activeSrcHeight the height of the active source region.
     */
    public void setActiveSrcHeight(int activeSrcHeight) {
        this.activeSrcHeight = activeSrcHeight;
    }

    Sets the TIFFColorConverter object describing the color space of the encoded data in the input stream. If no TIFFColorConverter is set, no conversion will be performed. 
Params: colorConverter – a TIFFColorConverter object, or null./**
     * Sets the {@code TIFFColorConverter} object describing the color
     * space of the encoded data in the input stream.  If no
     * {@code TIFFColorConverter} is set, no conversion will be performed.
     *
     * @param colorConverter a {@code TIFFColorConverter} object, or
     * {@code null}.
     */
    public void setColorConverter(TIFFColorConverter colorConverter) {
        this.colorConverter = colorConverter;
    }

    Returns an ImageTypeSpecifier describing an image whose underlying data array has the same format as the raw source pixel data. 
Returns: an ImageTypeSpecifier./**
     * Returns an {@code ImageTypeSpecifier} describing an image
     * whose underlying data array has the same format as the raw
     * source pixel data.
     *
     * @return an {@code ImageTypeSpecifier}.
     */
    public ImageTypeSpecifier getRawImageType() {
        ImageTypeSpecifier its =
            getRawImageTypeSpecifier(photometricInterpretation,
                                     compression,
                                     samplesPerPixel,
                                     bitsPerSample,
                                     sampleFormat,
                                     extraSamples,
                                     colorMap);
        return its;
    }

    Creates a BufferedImage whose underlying data array will be suitable for holding the raw decoded output of the decodeRaw method.  The default implementation calls getRawImageType, and calls the resulting ImageTypeSpecifier's createBufferedImage method. 
Returns: a BufferedImage whose underlying data array has the same format as the raw source pixel data, or null if it is not possible to create such an image./**
     * Creates a {@code BufferedImage} whose underlying data
     * array will be suitable for holding the raw decoded output of
     * the {@code decodeRaw} method.
     *
     * <p> The default implementation calls
     * {@code getRawImageType}, and calls the resulting
     * {@code ImageTypeSpecifier}'s
     * {@code createBufferedImage} method.
     *
     * @return a {@code BufferedImage} whose underlying data
     * array has the same format as the raw source pixel data, or
     * {@code null} if it is not possible to create such an
     * image.
     */
    public BufferedImage createRawImage() {
        if (planar) {
            // Create a single-banded image of the appropriate data type.

            // Get the number of bits per sample.
            int bps = bitsPerSample[sourceBands[0]];

            // Determine the data type.
            int dataType;
            if(sampleFormat[0] ==
               BaselineTIFFTagSet.SAMPLE_FORMAT_FLOATING_POINT) {
                if(bps <= 32) {
                    dataType = DataBuffer.TYPE_FLOAT;
                } else {
                    dataType = DataBuffer.TYPE_DOUBLE;
                }
            } else if(bps <= 8) {
                dataType = DataBuffer.TYPE_BYTE;
            } else if(bps <= 16) {
                if(sampleFormat[0] ==
                   BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER) {
                    dataType = DataBuffer.TYPE_SHORT;
                } else {
                    dataType = DataBuffer.TYPE_USHORT;
                }
            } else {
                dataType = DataBuffer.TYPE_INT;
            }

            ColorSpace csGray = ColorSpace.getInstance(ColorSpace.CS_GRAY);
            ImageTypeSpecifier its =
                ImageTypeSpecifier.createInterleaved(csGray,
                                                     new int[] {0},
                                                     dataType,
                                                     false,
                                                     false);

            return its.createBufferedImage(srcWidth, srcHeight);
        } else {
            ImageTypeSpecifier its = getRawImageType();
            if (its == null) {
                return null;
            }

            BufferedImage bi = its.createBufferedImage(srcWidth, srcHeight);
            return bi;
        }
    }

    Decodes the source data into the provided byte array b, starting at the offset given by dstOffset. Each pixel occupies bitsPerPixel bits, with no padding between pixels. Scanlines are separated by scanlineStride bytes. 
Params: b – a byte array to be written.
dstOffset – the starting offset in b to be written.
bitsPerPixel – the number of bits for each pixel.
scanlineStride – the number of bytes to advance between that starting pixels of each scanline.
Throws: IOException – if an error occurs reading from the source ImageInputStream./**
     * Decodes the source data into the provided {@code byte}
     * array {@code b}, starting at the offset given by
     * {@code dstOffset}.  Each pixel occupies
     * {@code bitsPerPixel} bits, with no padding between pixels.
     * Scanlines are separated by {@code scanlineStride}
     * {@code byte}s.
     *
     * @param b a {@code byte} array to be written.
     * @param dstOffset the starting offset in {@code b} to be
     * written.
     * @param bitsPerPixel the number of bits for each pixel.
     * @param scanlineStride the number of {@code byte}s to
     * advance between that starting pixels of each scanline.
     *
     * @throws IOException if an error occurs reading from the source
     * {@code ImageInputStream}.
     */
    public abstract void decodeRaw(byte[] b,
                                   int dstOffset,
                                   int bitsPerPixel,
                                   int scanlineStride) throws IOException;

    Decodes the source data into the provided short array s, starting at the offset given by dstOffset. Each pixel occupies bitsPerPixel bits, with no padding between pixels. Scanlines are separated by scanlineStride shorts  The default implementation calls decodeRaw(byte[] b,
...) and copies the resulting data into s. 
Params: s – a short array to be written.
dstOffset – the starting offset in s to be written.
bitsPerPixel – the number of bits for each pixel.
scanlineStride – the number of shorts to advance between that starting pixels of each scanline.
Throws: IOException – if an error occurs reading from the source ImageInputStream./**
     * Decodes the source data into the provided {@code short}
     * array {@code s}, starting at the offset given by
     * {@code dstOffset}.  Each pixel occupies
     * {@code bitsPerPixel} bits, with no padding between pixels.
     * Scanlines are separated by {@code scanlineStride}
     * {@code short}s
     *
     * <p> The default implementation calls {@code decodeRaw(byte[] b,
     * ...)} and copies the resulting data into {@code s}.
     *
     * @param s a {@code short} array to be written.
     * @param dstOffset the starting offset in {@code s} to be
     * written.
     * @param bitsPerPixel the number of bits for each pixel.
     * @param scanlineStride the number of {@code short}s to
     * advance between that starting pixels of each scanline.
     *
     * @throws IOException if an error occurs reading from the source
     * {@code ImageInputStream}.
     */
    public void decodeRaw(short[] s,
                          int dstOffset,
                          int bitsPerPixel,
                          int scanlineStride) throws IOException {
        int bytesPerRow = (srcWidth*bitsPerPixel + 7)/8;
        int shortsPerRow = bytesPerRow/2;

        byte[] b = new byte[bytesPerRow*srcHeight];
        decodeRaw(b, 0, bitsPerPixel, bytesPerRow);

        int bOffset = 0;
        if(stream.getByteOrder() == ByteOrder.BIG_ENDIAN) {
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < shortsPerRow; i++) {
                    short hiVal = b[bOffset++];
                    short loVal = b[bOffset++];
                    short sval = (short)((hiVal << 8) | (loVal & 0xff));
                    s[dstOffset + i] = sval;
                }

                dstOffset += scanlineStride;
            }
        } else { // ByteOrder.LITLE_ENDIAN
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < shortsPerRow; i++) {
                    short loVal = b[bOffset++];
                    short hiVal = b[bOffset++];
                    short sval = (short)((hiVal << 8) | (loVal & 0xff));
                    s[dstOffset + i] = sval;
                }

                dstOffset += scanlineStride;
            }
        }
    }

    Decodes the source data into the provided int array i, starting at the offset given by dstOffset. Each pixel occupies bitsPerPixel bits, with no padding between pixels. Scanlines are separated by scanlineStride ints.  The default implementation calls decodeRaw(byte[] b,
...) and copies the resulting data into i. 
Params: i – an int array to be written.
dstOffset – the starting offset in i to be written.
bitsPerPixel – the number of bits for each pixel.
scanlineStride – the number of ints to advance between that starting pixels of each scanline.
Throws: IOException – if an error occurs reading from the source ImageInputStream./**
     * Decodes the source data into the provided {@code int}
     * array {@code i}, starting at the offset given by
     * {@code dstOffset}.  Each pixel occupies
     * {@code bitsPerPixel} bits, with no padding between pixels.
     * Scanlines are separated by {@code scanlineStride}
     * {@code int}s.
     *
     * <p> The default implementation calls {@code decodeRaw(byte[] b,
     * ...)} and copies the resulting data into {@code i}.
     *
     * @param i an {@code int} array to be written.
     * @param dstOffset the starting offset in {@code i} to be
     * written.
     * @param bitsPerPixel the number of bits for each pixel.
     * @param scanlineStride the number of {@code int}s to
     * advance between that starting pixels of each scanline.
     *
     * @throws IOException if an error occurs reading from the source
     * {@code ImageInputStream}.
     */
    public void decodeRaw(int[] i,
                          int dstOffset,
                          int bitsPerPixel,
                          int scanlineStride) throws IOException {
        int numBands = bitsPerPixel/32;
        int intsPerRow = srcWidth*numBands;
        int bytesPerRow = intsPerRow*4;

        byte[] b = new byte[bytesPerRow*srcHeight];
        decodeRaw(b, 0, bitsPerPixel, bytesPerRow);

        int bOffset = 0;
        if(stream.getByteOrder() == ByteOrder.BIG_ENDIAN) {
            for (int j = 0; j < srcHeight; j++) {
                for (int k = 0; k < intsPerRow; k++) {
                    int v0 = b[bOffset++] & 0xff;
                    int v1 = b[bOffset++] & 0xff;
                    int v2 = b[bOffset++] & 0xff;
                    int v3 = b[bOffset++] & 0xff;
                    int ival = (v0 << 24) | (v1 << 16) | (v2 << 8) | v3;
                    i[dstOffset + k] = ival;
                }

                dstOffset += scanlineStride;
            }
        } else { // ByteOrder.LITLE_ENDIAN
            for (int j = 0; j < srcHeight; j++) {
                for (int k = 0; k < intsPerRow; k++) {
                    int v3 = b[bOffset++] & 0xff;
                    int v2 = b[bOffset++] & 0xff;
                    int v1 = b[bOffset++] & 0xff;
                    int v0 = b[bOffset++] & 0xff;
                    int ival = (v0 << 24) | (v1 << 16) | (v2 << 8) | v3;
                    i[dstOffset + k] = ival;
                }

                dstOffset += scanlineStride;
            }
        }
    }

    Decodes the source data into the provided float array f, starting at the offset given by dstOffset. Each pixel occupies bitsPerPixel bits, with no padding between pixels. Scanlines are separated by scanlineStride floats.  The default implementation calls decodeRaw(byte[] b,
...) and copies the resulting data into f. 
Params: f – a float array to be written.
dstOffset – the starting offset in f to be written.
bitsPerPixel – the number of bits for each pixel.
scanlineStride – the number of floats to advance between that starting pixels of each scanline.
Throws: IOException – if an error occurs reading from the source ImageInputStream./**
     * Decodes the source data into the provided {@code float}
     * array {@code f}, starting at the offset given by
     * {@code dstOffset}.  Each pixel occupies
     * {@code bitsPerPixel} bits, with no padding between pixels.
     * Scanlines are separated by {@code scanlineStride}
     * {@code float}s.
     *
     * <p> The default implementation calls {@code decodeRaw(byte[] b,
     * ...)} and copies the resulting data into {@code f}.
     *
     * @param f a {@code float} array to be written.
     * @param dstOffset the starting offset in {@code f} to be
     * written.
     * @param bitsPerPixel the number of bits for each pixel.
     * @param scanlineStride the number of {@code float}s to
     * advance between that starting pixels of each scanline.
     *
     * @throws IOException if an error occurs reading from the source
     * {@code ImageInputStream}.
     */
    public void decodeRaw(float[] f,
                          int dstOffset,
                          int bitsPerPixel,
                          int scanlineStride) throws IOException {
        int numBands = bitsPerPixel/32;
        int floatsPerRow = srcWidth*numBands;
        int bytesPerRow = floatsPerRow*4;

        byte[] b = new byte[bytesPerRow*srcHeight];
        decodeRaw(b, 0, bitsPerPixel, bytesPerRow);

        int bOffset = 0;
        if(stream.getByteOrder() == ByteOrder.BIG_ENDIAN) {
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < floatsPerRow; i++) {
                    int v0 = b[bOffset++] & 0xff;
                    int v1 = b[bOffset++] & 0xff;
                    int v2 = b[bOffset++] & 0xff;
                    int v3 = b[bOffset++] & 0xff;
                    int ival = (v0 << 24) | (v1 << 16) | (v2 << 8) | v3;
                    float fval = Float.intBitsToFloat(ival);
                    f[dstOffset + i] = fval;
                }

                dstOffset += scanlineStride;
            }
        } else { // ByteOrder.LITLE_ENDIAN
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < floatsPerRow; i++) {
                    int v3 = b[bOffset++] & 0xff;
                    int v2 = b[bOffset++] & 0xff;
                    int v1 = b[bOffset++] & 0xff;
                    int v0 = b[bOffset++] & 0xff;
                    int ival = (v0 << 24) | (v1 << 16) | (v2 << 8) | v3;
                    float fval = Float.intBitsToFloat(ival);
                    f[dstOffset + i] = fval;
                }

                dstOffset += scanlineStride;
            }
        }
    }

    Decodes the source data into the provided double array f, starting at the offset given by dstOffset. Each pixel occupies bitsPerPixel bits, with no padding between pixels. Scanlines are separated by scanlineStride doubles.  The default implementation calls decodeRaw(byte[] b,
...) and copies the resulting data into f. 
Params: d – a double array to be written.
dstOffset – the starting offset in f to be written.
bitsPerPixel – the number of bits for each pixel.
scanlineStride – the number of doubles to advance between that starting pixels of each scanline.
Throws: IOException – if an error occurs reading from the source ImageInputStream./**
     * Decodes the source data into the provided {@code double}
     * array {@code f}, starting at the offset given by
     * {@code dstOffset}.  Each pixel occupies
     * {@code bitsPerPixel} bits, with no padding between pixels.
     * Scanlines are separated by {@code scanlineStride}
     * {@code double}s.
     *
     * <p> The default implementation calls {@code decodeRaw(byte[] b,
     * ...)} and copies the resulting data into {@code f}.
     *
     * @param d a {@code double} array to be written.
     * @param dstOffset the starting offset in {@code f} to be
     * written.
     * @param bitsPerPixel the number of bits for each pixel.
     * @param scanlineStride the number of {@code double}s to
     * advance between that starting pixels of each scanline.
     *
     * @throws IOException if an error occurs reading from the source
     * {@code ImageInputStream}.
     */
    public void decodeRaw(double[] d,
                          int dstOffset,
                          int bitsPerPixel,
                          int scanlineStride) throws IOException {
        int numBands = bitsPerPixel/64;
        int doublesPerRow = srcWidth*numBands;
        int bytesPerRow = doublesPerRow*8;

        byte[] b = new byte[bytesPerRow*srcHeight];
        decodeRaw(b, 0, bitsPerPixel, bytesPerRow);

        int bOffset = 0;
        if(stream.getByteOrder() == ByteOrder.BIG_ENDIAN) {
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < doublesPerRow; i++) {
                    long v0 = b[bOffset++] & 0xff;
                    long v1 = b[bOffset++] & 0xff;
                    long v2 = b[bOffset++] & 0xff;
                    long v3 = b[bOffset++] & 0xff;
                    long v4 = b[bOffset++] & 0xff;
                    long v5 = b[bOffset++] & 0xff;
                    long v6 = b[bOffset++] & 0xff;
                    long v7 = b[bOffset++] & 0xff;
                    long lval =
                        (v0 << 56) | (v1 << 48) | (v2 << 40) | (v3 << 32)
                        | (v4 << 24) | (v5 << 16) | (v6 << 8) | v7;
                    double dval = Double.longBitsToDouble(lval);
                    d[dstOffset + i] = dval;
                }

                dstOffset += scanlineStride;
            }
        } else { // ByteOrder.LITLE_ENDIAN
            for (int j = 0; j < srcHeight; j++) {
                for (int i = 0; i < doublesPerRow; i++) {
                    long v7 = b[bOffset++] & 0xff;
                    long v6 = b[bOffset++] & 0xff;
                    long v5 = b[bOffset++] & 0xff;
                    long v4 = b[bOffset++] & 0xff;
                    long v3 = b[bOffset++] & 0xff;
                    long v2 = b[bOffset++] & 0xff;
                    long v1 = b[bOffset++] & 0xff;
                    long v0 = b[bOffset++] & 0xff;
                    long lval =
                        (v0 << 56) | (v1 << 48) | (v2 << 40) | (v3 << 32)
                        | (v4 << 24) | (v5 << 16) | (v6 << 8) | v7;
                    double dval = Double.longBitsToDouble(lval);
                    d[dstOffset + i] = dval;
                }

                dstOffset += scanlineStride;
            }
        }
    }

    //
    // Values used to prevent unneeded recalculation of bit adjustment table.
    //
    private boolean isFirstBitDepthTable = true;
    private boolean planarCache = false;
    private int[] destBitsPerSampleCache = null;
    private int[] sourceBandsCache = null;
    private int[] bitsPerSampleCache = null;
    private int[] destinationBandsCache = null;

    This routine is called prior to a sequence of calls to the decode method, in order to allow any necessary tables or other structures to be initialized based on metadata values. This routine is guaranteed to be called any time the metadata values have changed.  The default implementation computes tables used by the decode method to rescale components to different bit depths. Thus, if this method is overridden, it is important for the subclass method to call super(), unless it overrides decode as well. /**
     * This routine is called prior to a sequence of calls to the
     * {@code decode} method, in order to allow any necessary
     * tables or other structures to be initialized based on metadata
     * values.  This routine is guaranteed to be called any time the
     * metadata values have changed.
     *
     * <p> The default implementation computes tables used by the
     * {@code decode} method to rescale components to different
     * bit depths.  Thus, if this method is overridden, it is
     * important for the subclass method to call {@code super()},
     * unless it overrides {@code decode} as well.
     */
    public void beginDecoding() {
        // Note: This method assumes that sourceBands, destinationBands,
        // and bitsPerSample are all non-null which is true as they are
        // set up that way in TIFFImageReader. Also the lengths and content
        // of sourceBands and destinationBands are checked in TIFFImageReader
        // before the present method is invoked.

        // Determine if all of the relevant output bands have the
        // same bit depth as the source data
        this.adjustBitDepths = false;
        int numBands = destinationBands.length;
        int[] destBitsPerSample = null;
        if(planar) {
            int totalNumBands = bitsPerSample.length;
            destBitsPerSample = new int[totalNumBands];
            int dbps = image.getSampleModel().getSampleSize(0);
            for(int b = 0; b < totalNumBands; b++) {
                destBitsPerSample[b] = dbps;
            }
        } else {
            destBitsPerSample = image.getSampleModel().getSampleSize();
        }

        for (int b = 0; b < numBands; b++) {
            if (destBitsPerSample[destinationBands[b]] !=
                bitsPerSample[sourceBands[b]]) {
                adjustBitDepths = true;
                break;
            }
        }

        // If the bit depths differ, create a lookup table
        // per band to perform the conversion
        if(adjustBitDepths) {
            // Compute the table only if this is the first time one is
            // being computed or if any of the variables on which the
            // table is based have changed.
            if(this.isFirstBitDepthTable ||
               planar != planarCache ||
               !areIntArraysEqual(destBitsPerSample,
                                  destBitsPerSampleCache) ||
               !areIntArraysEqual(sourceBands,
                                  sourceBandsCache) ||
               !areIntArraysEqual(bitsPerSample,
                                  bitsPerSampleCache) ||
               !areIntArraysEqual(destinationBands,
                                  destinationBandsCache)) {

                this.isFirstBitDepthTable = false;

                // Cache some variables.
                this.planarCache = planar;
                this.destBitsPerSampleCache =
                    destBitsPerSample.clone(); // never null ...
                this.sourceBandsCache = sourceBands == null ?
                    null : sourceBands.clone();
                this.bitsPerSampleCache = bitsPerSample == null ?
                    null : bitsPerSample.clone();
                this.destinationBandsCache = destinationBands.clone();

                // Allocate and fill the table.
                bitDepthScale = new int[numBands][];
                for (int b = 0; b < numBands; b++) {
                    int maxInSample = (1 << bitsPerSample[sourceBands[b]]) - 1;
                    int halfMaxInSample = maxInSample/2;

                    int maxOutSample =
                        (1 << destBitsPerSample[destinationBands[b]]) - 1;

                    bitDepthScale[b] = new int[maxInSample + 1];
                    for (int s = 0; s <= maxInSample; s++) {
                        bitDepthScale[b][s] =
                            (s*maxOutSample + halfMaxInSample)/
                            maxInSample;
                    }
                }
            }
        } else { // !adjustBitDepths
            // Clear any prior table.
            this.bitDepthScale = null;
        }

        // Determine whether source and destination band lists are ramps.
        // Note that these conditions will be true for planar images if
        // and only if samplesPerPixel == 1, sourceBands[0] == 0, and
        // destinationBands[0] == 0. For the purposes of this method, the
        // only difference between such a planar image and a chunky image
        // is the setting of the PlanarConfiguration field.
        boolean sourceBandsNormal = false;
        boolean destinationBandsNormal = false;
        if (numBands == samplesPerPixel) {
            sourceBandsNormal = true;
            destinationBandsNormal = true;
            for (int i = 0; i < numBands; i++) {
                if (sourceBands[i] != i) {
                    sourceBandsNormal = false;
                }
                if (destinationBands[i] != i) {
                    destinationBandsNormal = false;
                }
            }
        }

        // Determine whether the image is bilevel and/or contiguous.
        // Note that a planar image could be bilevel but it will not
        // be contiguous unless it has a single component band stored
        // in a single bank.
        this.isBilevel =
            ImageUtil.isBinary(this.image.getRaster().getSampleModel());
        this.isContiguous = this.isBilevel ?
            true : ImageUtil.imageIsContiguous(this.image);

        // Analyze destination image to see if we can copy into it
        // directly

        this.isImageSimple =
            (colorConverter == null) &&
            (subsampleX == 1) && (subsampleY == 1) &&
            (srcWidth == dstWidth) && (srcHeight == dstHeight) &&
            ((dstMinX + dstWidth) <= image.getWidth()) &&
            ((dstMinY + dstHeight) <= image.getHeight()) &&
            sourceBandsNormal && destinationBandsNormal &&
            !adjustBitDepths;
    }

    Decodes the input bit stream (located in the ImageInputStream stream, at offset offset, and continuing for byteCount bytes) into the output BufferedImage image.  The default implementation analyzes the destination image to determine if it is suitable as the destination for the decodeRaw method. If not, a suitable image is created. Next, decodeRaw is called to perform the actual decoding, and the results are copied into the destination image if necessary. Subsampling and offsetting are performed automatically. 
 The precise responsibilities of this routine are as follows. The input bit stream is defined by the instance variables stream, offset, and byteCount. These bits contain the data for the region of the source image defined by srcMinX, srcMinY, srcWidth, and srcHeight. 
 The source data is required to be subsampling, starting at the sourceXOffsetth column and including every subsampleXth pixel thereafter (and similarly for sourceYOffset and subsampleY). 
 Pixels are copied into the destination with an addition shift of (dstXOffset, dstYOffset). The complete set of formulas relating the source and destination coordinate spaces are: 
dx = (sx - sourceXOffset)/subsampleX + dstXOffset;
dy = (sy - sourceYOffset)/subsampleY + dstYOffset;
 Only source pixels such that (sx - sourceXOffset) %
subsampleX == 0 and (sy - sourceYOffset) %
subsampleY == 0 are copied.  The inverse mapping, from destination to source coordinates,
is one-to-one:
sx = (dx - dstXOffset)*subsampleX + sourceXOffset;
sy = (dy - dstYOffset)*subsampleY + sourceYOffset;

 The region of the destination image to be updated is given by the instance variables dstMinX, dstMinY, dstWidth, and dstHeight. 
 It is possible that not all of the source data being read will contribute to the destination image. For example, the destination offsets could be set such that some of the source pixels land outside of the bounds of the image. As a convenience, the bounds of the active source region (that is, the region of the strip or tile being read that actually contributes to the destination image, taking clipping into account) are available as activeSrcMinX, activeSrcMinY, activeSrcWidth and activeSrcHeight. Thus, the source pixel at (activeSrcMinX, activeSrcMinY) will map to the destination pixel (dstMinX, dstMinY). 
 The sequence of source bands given by sourceBands are to be copied into the sequence of bands in the destination given by destinationBands. 
 Some standard tag information is provided the instance variables photometricInterpretation, compression, samplesPerPixel, bitsPerSample, sampleFormat, extraSamples, and colorMap. 
 In practice, unless there is a significant performance advantage to be gained by overriding this routine, most users will prefer to use the default implementation of this routine, and instead override the decodeRaw and/or getRawImageType methods. 
Throws: IOException – if an error occurs in decodeRaw./**
     * Decodes the input bit stream (located in the
     * {@code ImageInputStream} {@code stream}, at offset
     * {@code offset}, and continuing for {@code byteCount}
     * bytes) into the output {@code BufferedImage}
     * {@code image}.
     *
     * <p> The default implementation analyzes the destination image
     * to determine if it is suitable as the destination for the
     * {@code decodeRaw} method.  If not, a suitable image is
     * created.  Next, {@code decodeRaw} is called to perform the
     * actual decoding, and the results are copied into the
     * destination image if necessary.  Subsampling and offsetting are
     * performed automatically.
     *
     * <p> The precise responsibilities of this routine are as
     * follows.  The input bit stream is defined by the instance
     * variables {@code stream}, {@code offset}, and
     * {@code byteCount}.  These bits contain the data for the
     * region of the source image defined by {@code srcMinX},
     * {@code srcMinY}, {@code srcWidth}, and
     * {@code srcHeight}.
     *
     * <p> The source data is required to be subsampling, starting at
     * the {@code sourceXOffset}th column and including
     * every {@code subsampleX}th pixel thereafter (and similarly
     * for {@code sourceYOffset} and
     * {@code subsampleY}).
     *
     * <p> Pixels are copied into the destination with an addition shift of
     * ({@code dstXOffset}, {@code dstYOffset}).  The complete
     * set of formulas relating the source and destination coordinate spaces
     * are:
     *
     * <pre>
     * dx = (sx - sourceXOffset)/subsampleX + dstXOffset;
     * dy = (sy - sourceYOffset)/subsampleY + dstYOffset;
     * </pre>
     *
     * Only source pixels such that {@code (sx - sourceXOffset) %
     * subsampleX == 0} and {@code (sy - sourceYOffset) %
     * subsampleY == 0} are copied.
     *
     * <p> The inverse mapping, from destination to source coordinates,
     * is one-to-one:
     *
     * <pre>
     * sx = (dx - dstXOffset)*subsampleX + sourceXOffset;
     * sy = (dy - dstYOffset)*subsampleY + sourceYOffset;
     * </pre>
     *
     * <p> The region of the destination image to be updated is given
     * by the instance variables {@code dstMinX},
     * {@code dstMinY}, {@code dstWidth}, and
     * {@code dstHeight}.
     *
     * <p> It is possible that not all of the source data being read
     * will contribute to the destination image.  For example, the
     * destination offsets could be set such that some of the source
     * pixels land outside of the bounds of the image.  As a
     * convenience, the bounds of the active source region (that is,
     * the region of the strip or tile being read that actually
     * contributes to the destination image, taking clipping into
     * account) are available as {@code activeSrcMinX},
     * {@code activeSrcMinY}, {@code activeSrcWidth} and
     * {@code activeSrcHeight}.  Thus, the source pixel at
     * ({@code activeSrcMinX}, {@code activeSrcMinY}) will
     * map to the destination pixel ({@code dstMinX},
     * {@code dstMinY}).
     *
     * <p> The sequence of source bands given by
     * {@code sourceBands} are to be copied into the sequence of
     * bands in the destination given by
     * {@code destinationBands}.
     *
     * <p> Some standard tag information is provided the instance
     * variables {@code photometricInterpretation},
     * {@code compression}, {@code samplesPerPixel},
     * {@code bitsPerSample}, {@code sampleFormat},
     * {@code extraSamples}, and {@code colorMap}.
     *
     * <p> In practice, unless there is a significant performance
     * advantage to be gained by overriding this routine, most users
     * will prefer to use the default implementation of this routine,
     * and instead override the {@code decodeRaw} and/or
     * {@code getRawImageType} methods.
     *
     * @exception IOException if an error occurs in
     * {@code decodeRaw}.
     */
    public void decode() throws IOException {
        byte[] byteData = null;
        short[] shortData = null;
        int[] intData = null;
        float[] floatData = null;
        double[] doubleData = null;

        int dstOffset = 0;
        int pixelBitStride = 1;
        int scanlineStride = 0;

        // Analyze raw image

        this.rawImage = null;
        if(isImageSimple) {
            if(isBilevel) {
                rawImage = this.image;
            } else if (isContiguous) {
                rawImage =
                    image.getSubimage(dstMinX, dstMinY, dstWidth, dstHeight);
            }
        }

        boolean isDirectCopy = rawImage != null;

        if(rawImage == null) {
            rawImage = createRawImage();
            if (rawImage == null) {
                throw new IIOException("Couldn't create image buffer!");
            }
        }

        WritableRaster ras = rawImage.getRaster();

        if(isBilevel) {
            Rectangle rect = isImageSimple ?
                new Rectangle(dstMinX, dstMinY, dstWidth, dstHeight) :
                ras.getBounds();
            byteData = ImageUtil.getPackedBinaryData(ras, rect);
            dstOffset = 0;
            pixelBitStride = 1;
            scanlineStride = (rect.width + 7)/8;
        } else {
            SampleModel sm = ras.getSampleModel();
            DataBuffer db = ras.getDataBuffer();

            boolean isSupportedType = false;

            if (sm instanceof ComponentSampleModel) {
                ComponentSampleModel csm = (ComponentSampleModel)sm;
                dstOffset = csm.getOffset(-ras.getSampleModelTranslateX(),
                                          -ras.getSampleModelTranslateY());
                scanlineStride = csm.getScanlineStride();
                if(db instanceof DataBufferByte) {
                    DataBufferByte dbb = (DataBufferByte)db;

                    byteData = dbb.getData();
                    pixelBitStride = csm.getPixelStride()*8;
                    isSupportedType = true;
                } else if(db instanceof DataBufferUShort) {
                    DataBufferUShort dbus = (DataBufferUShort)db;

                    shortData = dbus.getData();
                    pixelBitStride = csm.getPixelStride()*16;
                    isSupportedType = true;
                } else if(db instanceof DataBufferShort) {
                    DataBufferShort dbs = (DataBufferShort)db;

                    shortData = dbs.getData();
                    pixelBitStride = csm.getPixelStride()*16;
                    isSupportedType = true;
                } else if(db instanceof DataBufferInt) {
                    DataBufferInt dbi = (DataBufferInt)db;

                    intData = dbi.getData();
                    pixelBitStride = csm.getPixelStride()*32;
                    isSupportedType = true;
                } else if(db instanceof DataBufferFloat) {
                    DataBufferFloat dbf = (DataBufferFloat)db;

                    floatData = dbf.getData();
                    pixelBitStride = csm.getPixelStride()*32;
                    isSupportedType = true;
                } else if(db instanceof DataBufferDouble) {
                    DataBufferDouble dbd = (DataBufferDouble)db;

                    doubleData = dbd.getData();
                    pixelBitStride = csm.getPixelStride()*64;
                    isSupportedType = true;
                }
            } else if (sm instanceof MultiPixelPackedSampleModel) {
                MultiPixelPackedSampleModel mppsm =
                    (MultiPixelPackedSampleModel)sm;
                dstOffset =
                    mppsm.getOffset(-ras.getSampleModelTranslateX(),
                                    -ras.getSampleModelTranslateY());
                pixelBitStride = mppsm.getPixelBitStride();
                scanlineStride = mppsm.getScanlineStride();
                if(db instanceof DataBufferByte) {
                    DataBufferByte dbb = (DataBufferByte)db;

                    byteData = dbb.getData();
                    isSupportedType = true;
                } else if(db instanceof DataBufferUShort) {
                    DataBufferUShort dbus = (DataBufferUShort)db;

                    shortData = dbus.getData();
                    isSupportedType = true;
                } else if(db instanceof DataBufferInt) {
                    DataBufferInt dbi = (DataBufferInt)db;

                    intData = dbi.getData();
                    isSupportedType = true;
                }
            } else if (sm instanceof SinglePixelPackedSampleModel) {
                SinglePixelPackedSampleModel sppsm =
                    (SinglePixelPackedSampleModel)sm;
                dstOffset =
                    sppsm.getOffset(-ras.getSampleModelTranslateX(),
                                    -ras.getSampleModelTranslateY());
                scanlineStride = sppsm.getScanlineStride();
                if(db instanceof DataBufferByte) {
                    DataBufferByte dbb = (DataBufferByte)db;

                    byteData = dbb.getData();
                    pixelBitStride = 8;
                    isSupportedType = true;
                } else if(db instanceof DataBufferUShort) {
                    DataBufferUShort dbus = (DataBufferUShort)db;

                    shortData = dbus.getData();
                    pixelBitStride = 16;
                    isSupportedType = true;
                } else if(db instanceof DataBufferInt) {
                    DataBufferInt dbi = (DataBufferInt)db;

                    intData = dbi.getData();
                    pixelBitStride = 32;
                    isSupportedType = true;
                }
            }

            if(!isSupportedType) {
                throw new IIOException
                    ("Unsupported raw image type: SampleModel = "+sm+
                     "; DataBuffer = "+db);
            }
        }

        if(isBilevel) {
            // Bilevel data are always in a contiguous byte buffer.
            decodeRaw(byteData, dstOffset, pixelBitStride, scanlineStride);
        } else {
            SampleModel sm = ras.getSampleModel();

            // Branch based on whether data are bit-contiguous, i.e.,
            // data are packaed as tightly as possible leaving no unused
            // bits except at the end of a row.
            if(isDataBufferBitContiguous(sm, bitsPerSample)) {
                // Use byte or float data directly.
                if (byteData != null) {
                    decodeRaw(byteData, dstOffset,
                              pixelBitStride, scanlineStride);
                } else if (floatData != null) {
                    decodeRaw(floatData, dstOffset,
                              pixelBitStride, scanlineStride);
                } else if (doubleData != null) {
                    decodeRaw(doubleData, dstOffset,
                              pixelBitStride, scanlineStride);
                } else {
                    if (shortData != null) {
                        if(areSampleSizesEqual(sm) &&
                           sm.getSampleSize(0) == 16) {
                            // Decode directly into short data.
                            decodeRaw(shortData, dstOffset,
                                      pixelBitStride, scanlineStride);
                        } else {
                            // Decode into bytes and reformat into shorts.
                            int bpp = getBitsPerPixel(sm);
                            int bytesPerRow = (bpp*srcWidth + 7)/8;
                            byte[] buf = new byte[bytesPerRow*srcHeight];
                            decodeRaw(buf, 0, bpp, bytesPerRow);
                            reformatData(buf, bytesPerRow, srcHeight,
                                         shortData, null,
                                         dstOffset, scanlineStride);
                        }
                    } else if (intData != null) {
                        if(areSampleSizesEqual(sm) &&
                           sm.getSampleSize(0) == 32) {
                            // Decode directly into int data.
                            decodeRaw(intData, dstOffset,
                                      pixelBitStride, scanlineStride);
                        } else {
                            // Decode into bytes and reformat into ints.
                            int bpp = getBitsPerPixel(sm);
                            int bytesPerRow = (bpp*srcWidth + 7)/8;
                            byte[] buf = new byte[bytesPerRow*srcHeight];
                            decodeRaw(buf, 0, bpp, bytesPerRow);
                            reformatData(buf, bytesPerRow, srcHeight,
                                         null, intData,
                                         dstOffset, scanlineStride);
                        }
                    }
                }
            } else {
                // Read discontiguous data into bytes and set the samples
                // into the Raster.
                int bpp;
                if (planar) {
                    bpp = bitsPerSample[planarBand];
                } else {
                    bpp = 0;
                    for (int bps : bitsPerSample) {
                        bpp += bps;
                    }
                }
                int bytesPerRow = (bpp*srcWidth + 7)/8;
                byte[] buf = new byte[bytesPerRow*srcHeight];
                decodeRaw(buf, 0, bpp, bytesPerRow);
                reformatDiscontiguousData(buf, bitsPerSample, bytesPerRow,
                                          srcWidth, srcHeight,
                                          ras);
            }
        }

        if (colorConverter != null) {
            float[] rgb = new float[3];

            if(byteData != null) {
                for (int j = 0; j < dstHeight; j++) {
                    int idx = dstOffset;
                    for (int i = 0; i < dstWidth; i++) {
                        float x0 = (float)(byteData[idx] & 0xff);
                        float x1 = (float)(byteData[idx + 1] & 0xff);
                        float x2 = (float)(byteData[idx + 2] & 0xff);

                        colorConverter.toRGB(x0, x1, x2, rgb);

                        byteData[idx] = (byte)(rgb[0]);
                        byteData[idx + 1] = (byte)(rgb[1]);
                        byteData[idx + 2] = (byte)(rgb[2]);

                        idx += 3;
                    }

                    dstOffset += scanlineStride;
                }
            } else if(shortData != null) {
                if(sampleFormat[0] ==
                   BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER) {
                    for (int j = 0; j < dstHeight; j++) {
                        int idx = dstOffset;
                        for (int i = 0; i < dstWidth; i++) {
                            float x0 = (float)shortData[idx];
                            float x1 = (float)shortData[idx + 1];
                            float x2 = (float)shortData[idx + 2];

                            colorConverter.toRGB(x0, x1, x2, rgb);

                            shortData[idx] = (short)(rgb[0]);
                            shortData[idx + 1] = (short)(rgb[1]);
                            shortData[idx + 2] = (short)(rgb[2]);

                            idx += 3;
                        }

                        dstOffset += scanlineStride;
                    }
                } else {
                    for (int j = 0; j < dstHeight; j++) {
                        int idx = dstOffset;
                        for (int i = 0; i < dstWidth; i++) {
                            float x0 = (float)(shortData[idx] & 0xffff);
                            float x1 = (float)(shortData[idx + 1] & 0xffff);
                            float x2 = (float)(shortData[idx + 2] & 0xffff);

                            colorConverter.toRGB(x0, x1, x2, rgb);

                            shortData[idx] = (short)(rgb[0]);
                            shortData[idx + 1] = (short)(rgb[1]);
                            shortData[idx + 2] = (short)(rgb[2]);

                            idx += 3;
                        }

                        dstOffset += scanlineStride;
                    }
                }
            } else if(intData != null) {
                for (int j = 0; j < dstHeight; j++) {
                    int idx = dstOffset;
                    for (int i = 0; i < dstWidth; i++) {
                        float x0 = (float)intData[idx];
                        float x1 = (float)intData[idx + 1];
                        float x2 = (float)intData[idx + 2];

                        colorConverter.toRGB(x0, x1, x2, rgb);

                        intData[idx] = (int)(rgb[0]);
                        intData[idx + 1] = (int)(rgb[1]);
                        intData[idx + 2] = (int)(rgb[2]);

                        idx += 3;
                    }

                    dstOffset += scanlineStride;
                }
            } else if(floatData != null) {
                for (int j = 0; j < dstHeight; j++) {
                    int idx = dstOffset;
                    for (int i = 0; i < dstWidth; i++) {
                        float x0 = floatData[idx];
                        float x1 = floatData[idx + 1];
                        float x2 = floatData[idx + 2];

                        colorConverter.toRGB(x0, x1, x2, rgb);

                        floatData[idx] = rgb[0];
                        floatData[idx + 1] = rgb[1];
                        floatData[idx + 2] = rgb[2];

                        idx += 3;
                    }

                    dstOffset += scanlineStride;
                }
            } else if(doubleData != null) {
                for (int j = 0; j < dstHeight; j++) {
                    int idx = dstOffset;
                    for (int i = 0; i < dstWidth; i++) {
                        // Note: Possible loss of precision.
                        float x0 = (float)doubleData[idx];
                        float x1 = (float)doubleData[idx + 1];
                        float x2 = (float)doubleData[idx + 2];

                        colorConverter.toRGB(x0, x1, x2, rgb);

                        doubleData[idx] = rgb[0];
                        doubleData[idx + 1] = rgb[1];
                        doubleData[idx + 2] = rgb[2];

                        idx += 3;
                    }

                    dstOffset += scanlineStride;
                }
            }
        }

        if (photometricInterpretation ==
            BaselineTIFFTagSet.PHOTOMETRIC_INTERPRETATION_WHITE_IS_ZERO) {
            if(byteData != null) {
                int bytesPerRow = (srcWidth*pixelBitStride + 7)/8;
                for (int y = 0; y < srcHeight; y++) {
                    int offset = dstOffset + y*scanlineStride;
                    for (int i = 0; i < bytesPerRow; i++) {
                        byteData[offset + i] ^= 0xff;
                    }
                }
            } else if(shortData != null) {
                int shortsPerRow = (srcWidth*pixelBitStride + 15)/16;
                if(sampleFormat[0] ==
                   BaselineTIFFTagSet.SAMPLE_FORMAT_SIGNED_INTEGER) {
                    for (int y = 0; y < srcHeight; y++) {
                        int offset = dstOffset + y*scanlineStride;
                        for (int i = 0; i < shortsPerRow; i++) {
                            int shortOffset = offset + i;
                            shortData[shortOffset] =
                                (short)(Short.MAX_VALUE -
                                        shortData[shortOffset]);
                        }
                    }
                } else {
                    for (int y = 0; y < srcHeight; y++) {
                        int offset = dstOffset + y*scanlineStride;
                        for (int i = 0; i < shortsPerRow; i++) {
                            shortData[offset + i] ^= 0xffff;
                        }
                    }
                }
            } else if(intData != null) {
                int intsPerRow = (srcWidth*pixelBitStride + 31)/32;
                for (int y = 0; y < srcHeight; y++) {
                    int offset = dstOffset + y*scanlineStride;
                    for (int i = 0; i < intsPerRow; i++) {
                        int intOffset = offset + i;
                        intData[intOffset] =
                            Integer.MAX_VALUE - intData[intOffset];
                    }
                }
            } else if(floatData != null) {
                int floatsPerRow = (srcWidth*pixelBitStride + 31)/32;
                for (int y = 0; y < srcHeight; y++) {
                    int offset = dstOffset + y*scanlineStride;
                    for (int i = 0; i < floatsPerRow; i++) {
                        int floatOffset = offset + i;
                        floatData[floatOffset] =
                            1.0F - floatData[floatOffset];
                    }
                }
            } else if(doubleData != null) {
                int doublesPerRow = (srcWidth*pixelBitStride + 63)/64;
                for (int y = 0; y < srcHeight; y++) {
                    int offset = dstOffset + y*scanlineStride;
                    for (int i = 0; i < doublesPerRow; i++) {
                        int doubleOffset = offset + i;
                        doubleData[doubleOffset] =
                            1.0F - doubleData[doubleOffset];
                    }
                }
            }
        }

        if(isBilevel) {
            Rectangle rect = isImageSimple ?
                new Rectangle(dstMinX, dstMinY, dstWidth, dstHeight) :
                ras.getBounds();
            ImageUtil.setPackedBinaryData(byteData, ras, rect);
        }

        if (isDirectCopy) { // rawImage == image) {
            return;
        }

        // Copy the raw image data into the true destination image
        Raster src = rawImage.getRaster();

        // Create band child of source
        Raster srcChild = src.createChild(0, 0,
                                          srcWidth, srcHeight,
                                          srcMinX, srcMinY,
                                          planar ? null : sourceBands);

        WritableRaster dst = image.getRaster();

        // Create dst child covering area and bands to be written
        WritableRaster dstChild = dst.createWritableChild(dstMinX, dstMinY,
                                                          dstWidth, dstHeight,
                                                          dstMinX, dstMinY,
                                                          destinationBands);

        if (subsampleX == 1 && subsampleY == 1 && !adjustBitDepths) {
            srcChild = srcChild.createChild(activeSrcMinX,
                                            activeSrcMinY,
                                            activeSrcWidth, activeSrcHeight,
                                            dstMinX, dstMinY,
                                            null);

            dstChild.setRect(srcChild);
        } else if (subsampleX == 1 && !adjustBitDepths) {
            int sy = activeSrcMinY;
            int dy = dstMinY;
            while (sy < srcMinY + srcHeight) {
                Raster srcRow = srcChild.createChild(activeSrcMinX, sy,
                                                     activeSrcWidth, 1,
                                                     dstMinX, dy,
                                                     null);
                dstChild.setRect(srcRow);

                sy += subsampleY;
                ++dy;
            }
        } else {
            int[] p = srcChild.getPixel(srcMinX, srcMinY, (int[])null);
            int numBands = p.length;

            int sy = activeSrcMinY;
            int dy = dstMinY;

            while (sy < activeSrcMinY + activeSrcHeight) {
                int sx = activeSrcMinX;
                int dx = dstMinX;

                while (sx < activeSrcMinX + activeSrcWidth) {
                    srcChild.getPixel(sx, sy, p);
                    if (adjustBitDepths) {
                        for (int band = 0; band < numBands; band++) {
                            p[band] = bitDepthScale[band][p[band]];
                        }
                    }
                    dstChild.setPixel(dx, dy, p);

                    sx += subsampleX;
                    ++dx;
                }

                sy += subsampleY;
                ++dy;
            }
        }
    }
}
Params:	dataType – The data type (DataBuffer.TYPE_*). numBands – The number of bands.
Returns:	A `PixelInterleavedSampleModel`.
Params:	subsampleX – the horizontal subsampling factor.
Throws:	IllegalArgumentException – if `subsampleX` is less than or equal to 0.
Params:	subsampleY – the vertical subsampling factor.
Throws:	IllegalArgumentException – if `subsampleY` is less than or equal to 0.
Params:	b – a `byte` array to be written. dstOffset – the starting offset in `b` to be written. bitsPerPixel – the number of bits for each pixel. scanlineStride – the number of `byte`s to advance between that starting pixels of each scanline.
Throws:	IOException – if an error occurs reading from the source `ImageInputStream`.
Params:	s – a `short` array to be written. dstOffset – the starting offset in `s` to be written. bitsPerPixel – the number of bits for each pixel. scanlineStride – the number of `short`s to advance between that starting pixels of each scanline.
Throws:	IOException – if an error occurs reading from the source `ImageInputStream`.
Params:	i – an `int` array to be written. dstOffset – the starting offset in `i` to be written. bitsPerPixel – the number of bits for each pixel. scanlineStride – the number of `int`s to advance between that starting pixels of each scanline.
Throws:	IOException – if an error occurs reading from the source `ImageInputStream`.
Params:	f – a `float` array to be written. dstOffset – the starting offset in `f` to be written. bitsPerPixel – the number of bits for each pixel. scanlineStride – the number of `float`s to advance between that starting pixels of each scanline.
Throws:	IOException – if an error occurs reading from the source `ImageInputStream`.
Params:	d – a `double` array to be written. dstOffset – the starting offset in `f` to be written. bitsPerPixel – the number of bits for each pixel. scanlineStride – the number of `double`s to advance between that starting pixels of each scanline.
Throws:	IOException – if an error occurs reading from the source `ImageInputStream`.
/

java/ 15/ java.desktop/com/sun/imageio/plugins/tiff/TIFFDecompressor.java
