https://openjdk.java.net/ 
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 * Copyright (c) 1995, 2013, 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
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 */

package java.awt.image;

import java.util.Hashtable;
import java.awt.image.ImageProducer;
import java.awt.image.ImageConsumer;
import java.awt.image.ColorModel;
import java.awt.Image;


The PixelGrabber class implements an ImageConsumer which can be attached
to an Image or ImageProducer object to retrieve a subset of the pixels
in that image.  Here is an example:


public void handlesinglepixel(int x, int y, int pixel) {
     int alpha = (pixel >> 24) & 0xff;
     int red   = (pixel >> 16) & 0xff;
     int green = (pixel >>  8) & 0xff;
     int blue  = (pixel      ) & 0xff;
     // Deal with the pixel as necessary...
 }
public void handlepixels(Image img, int x, int y, int w, int h) {
     int[] pixels = new int[w * h];
     PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
     try {
         pg.grabPixels();
     } catch (InterruptedException e) {
         System.err.println("interrupted waiting for pixels!");
         return;
     }
     if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
         System.err.println("image fetch aborted or errored");
         return;
     }
     for (int j = 0; j < h; j++) {
         for (int i = 0; i < w; i++) {
             handlesinglepixel(x+i, y+j, pixels[j * w + i]);
         }
     }
 }



Author:     Jim Graham
See Also:
/**
 * The PixelGrabber class implements an ImageConsumer which can be attached
 * to an Image or ImageProducer object to retrieve a subset of the pixels
 * in that image.  Here is an example:
 * <pre>{@code
 *
 * public void handlesinglepixel(int x, int y, int pixel) {
 *      int alpha = (pixel >> 24) & 0xff;
 *      int red   = (pixel >> 16) & 0xff;
 *      int green = (pixel >>  8) & 0xff;
 *      int blue  = (pixel      ) & 0xff;
 *      // Deal with the pixel as necessary...
 * }
 *
 * public void handlepixels(Image img, int x, int y, int w, int h) {
 *      int[] pixels = new int[w * h];
 *      PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
 *      try {
 *          pg.grabPixels();
 *      } catch (InterruptedException e) {
 *          System.err.println("interrupted waiting for pixels!");
 *          return;
 *      }
 *      if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
 *          System.err.println("image fetch aborted or errored");
 *          return;
 *      }
 *      for (int j = 0; j < h; j++) {
 *          for (int i = 0; i < w; i++) {
 *              handlesinglepixel(x+i, y+j, pixels[j * w + i]);
 *          }
 *      }
 * }
 *
 * }</pre>
 *
 * @see ColorModel#getRGBdefault
 *
 * @author      Jim Graham
 */
public class PixelGrabber implements ImageConsumer {
    ImageProducer producer;

    int dstX;
    int dstY;
    int dstW;
    int dstH;

    ColorModel imageModel;
    byte[] bytePixels;
    int[] intPixels;
    int dstOff;
    int dstScan;

    private boolean grabbing;
    private int flags;

    private static final int GRABBEDBITS = (ImageObserver.FRAMEBITS
                                            | ImageObserver.ALLBITS);
    private static final int DONEBITS = (GRABBEDBITS
                                         | ImageObserver.ERROR);

    
Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the specified image into the given array. The pixels are stored into the array in the default RGB ColorModel. The RGB data for pixel (i, j) where (i, j) is inside the rectangle (x, y, w, h) is stored in the array at pix[(j - y) * scansize + (i - x) + off]. 
Params:
  • img – the image to retrieve pixels from
  • x – the x coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image, relative to the default
(unscaled) size of the image
  • y – the y coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image
  • w – the width of the rectangle of pixels to retrieve
  • h – the height of the rectangle of pixels to retrieve
  • pix – the array of integers which are to be used to hold the
RGB pixels retrieved from the image
  • off – the offset into the array of where to store the first pixel
  • scansize – the distance from one row of pixels to the next in
the array
See Also:
/**
     * Create a PixelGrabber object to grab the (x, y, w, h) rectangular
     * section of pixels from the specified image into the given array.
     * The pixels are stored into the array in the default RGB ColorModel.
     * The RGB data for pixel (i, j) where (i, j) is inside the rectangle
     * (x, y, w, h) is stored in the array at
     * {@code pix[(j - y) * scansize + (i - x) + off]}.
     * @see ColorModel#getRGBdefault
     * @param img the image to retrieve pixels from
     * @param x the x coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image, relative to the default
     * (unscaled) size of the image
     * @param y the y coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image
     * @param w the width of the rectangle of pixels to retrieve
     * @param h the height of the rectangle of pixels to retrieve
     * @param pix the array of integers which are to be used to hold the
     * RGB pixels retrieved from the image
     * @param off the offset into the array of where to store the first pixel
     * @param scansize the distance from one row of pixels to the next in
     * the array
     */
    public PixelGrabber(Image img, int x, int y, int w, int h,
                        int[] pix, int off, int scansize) {
        this(img.getSource(), x, y, w, h, pix, off, scansize);
    }

    
Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the image produced by the specified ImageProducer into the given array. The pixels are stored into the array in the default RGB ColorModel. The RGB data for pixel (i, j) where (i, j) is inside the rectangle (x, y, w, h) is stored in the array at pix[(j - y) * scansize + (i - x) + off]. 
Params:
  • ip – the ImageProducer that produces the image from which to retrieve pixels
  • x – the x coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image, relative to the default
(unscaled) size of the image
  • y – the y coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image
  • w – the width of the rectangle of pixels to retrieve
  • h – the height of the rectangle of pixels to retrieve
  • pix – the array of integers which are to be used to hold the
RGB pixels retrieved from the image
  • off – the offset into the array of where to store the first pixel
  • scansize – the distance from one row of pixels to the next in
the array
See Also:
/**
     * Create a PixelGrabber object to grab the (x, y, w, h) rectangular
     * section of pixels from the image produced by the specified
     * ImageProducer into the given array.
     * The pixels are stored into the array in the default RGB ColorModel.
     * The RGB data for pixel (i, j) where (i, j) is inside the rectangle
     * (x, y, w, h) is stored in the array at
     * {@code pix[(j - y) * scansize + (i - x) + off]}.
     * @param ip the {@code ImageProducer} that produces the
     * image from which to retrieve pixels
     * @param x the x coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image, relative to the default
     * (unscaled) size of the image
     * @param y the y coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image
     * @param w the width of the rectangle of pixels to retrieve
     * @param h the height of the rectangle of pixels to retrieve
     * @param pix the array of integers which are to be used to hold the
     * RGB pixels retrieved from the image
     * @param off the offset into the array of where to store the first pixel
     * @param scansize the distance from one row of pixels to the next in
     * the array
     * @see ColorModel#getRGBdefault
     */
    public PixelGrabber(ImageProducer ip, int x, int y, int w, int h,
                        int[] pix, int off, int scansize) {
        producer = ip;
        dstX = x;
        dstY = y;
        dstW = w;
        dstH = h;
        dstOff = off;
        dstScan = scansize;
        intPixels = pix;
        imageModel = ColorModel.getRGBdefault();
    }

    
Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the specified image. The pixels are accumulated in the original ColorModel if the same ColorModel is used for every call to setPixels, otherwise the pixels are accumulated in the default RGB ColorModel. If the forceRGB parameter is true, then the pixels will be accumulated in the default RGB ColorModel anyway. A buffer is allocated by the PixelGrabber to hold the pixels in either case. If (w < 0) or (h < 0), then they will default to the remaining width and height of the source data when that information is delivered. 
Params:
  • img – the image to retrieve the image data from
  • x – the x coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image, relative to the default
(unscaled) size of the image
  • y – the y coordinate of the upper left corner of the rectangle
of pixels to retrieve from the image
  • w – the width of the rectangle of pixels to retrieve
  • h – the height of the rectangle of pixels to retrieve
  • forceRGB – true if the pixels should always be converted to
the default RGB ColorModel
/**
     * Create a PixelGrabber object to grab the (x, y, w, h) rectangular
     * section of pixels from the specified image.  The pixels are
     * accumulated in the original ColorModel if the same ColorModel
     * is used for every call to setPixels, otherwise the pixels are
     * accumulated in the default RGB ColorModel.  If the forceRGB
     * parameter is true, then the pixels will be accumulated in the
     * default RGB ColorModel anyway.  A buffer is allocated by the
     * PixelGrabber to hold the pixels in either case.  If {@code (w < 0)} or
     * {@code (h < 0)}, then they will default to the remaining width and
     * height of the source data when that information is delivered.
     * @param img the image to retrieve the image data from
     * @param x the x coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image, relative to the default
     * (unscaled) size of the image
     * @param y the y coordinate of the upper left corner of the rectangle
     * of pixels to retrieve from the image
     * @param w the width of the rectangle of pixels to retrieve
     * @param h the height of the rectangle of pixels to retrieve
     * @param forceRGB true if the pixels should always be converted to
     * the default RGB ColorModel
     */
    public PixelGrabber(Image img, int x, int y, int w, int h,
                        boolean forceRGB)
    {
        producer = img.getSource();
        dstX = x;
        dstY = y;
        dstW = w;
        dstH = h;
        if (forceRGB) {
            imageModel = ColorModel.getRGBdefault();
        }
    }

    
Request the PixelGrabber to start fetching the pixels.

/**
     * Request the PixelGrabber to start fetching the pixels.
     */
    public synchronized void startGrabbing() {
        if ((flags & DONEBITS) != 0) {
            return;
        }
        if (!grabbing) {
            grabbing = true;
            flags &= ~(ImageObserver.ABORT);
            producer.startProduction(this);
        }
    }

    
Request the PixelGrabber to abort the image fetch.

/**
     * Request the PixelGrabber to abort the image fetch.
     */
    public synchronized void abortGrabbing() {
        imageComplete(IMAGEABORTED);
    }

    
Request the Image or ImageProducer to start delivering pixels and
wait for all of the pixels in the rectangle of interest to be
delivered.

Throws:
Returns:true if the pixels were successfully grabbed, false on
abort, error or timeout
/**
     * Request the Image or ImageProducer to start delivering pixels and
     * wait for all of the pixels in the rectangle of interest to be
     * delivered.
     * @return true if the pixels were successfully grabbed, false on
     * abort, error or timeout
     * @exception InterruptedException
     *            Another thread has interrupted this thread.
     */
    public boolean grabPixels() throws InterruptedException {
        return grabPixels(0);
    }

    
Request the Image or ImageProducer to start delivering pixels and wait for all of the pixels in the rectangle of interest to be delivered or until the specified timeout has elapsed. This method behaves in the following ways, depending on the value of ms: 
    

  •  If ms == 0, waits until all pixels are delivered 
  •  If ms > 0, waits until all pixels are delivered as timeout expires. 
  •  If ms < 0, returns true if all pixels are grabbed, false otherwise and does not wait. 


Params:
  • ms – the number of milliseconds to wait for the image pixels
to arrive before timing out
Throws:
Returns:true if the pixels were successfully grabbed, false on
abort, error or timeout
/**
     * Request the Image or ImageProducer to start delivering pixels and
     * wait for all of the pixels in the rectangle of interest to be
     * delivered or until the specified timeout has elapsed.  This method
     * behaves in the following ways, depending on the value of
     * {@code ms}:
     * <ul>
     * <li> If {@code ms == 0}, waits until all pixels are delivered
     * <li> If {@code ms > 0}, waits until all pixels are delivered
     * as timeout expires.
     * <li> If {@code ms < 0}, returns {@code true} if all pixels
     * are grabbed, {@code false} otherwise and does not wait.
     * </ul>
     * @param ms the number of milliseconds to wait for the image pixels
     * to arrive before timing out
     * @return true if the pixels were successfully grabbed, false on
     * abort, error or timeout
     * @exception InterruptedException
     *            Another thread has interrupted this thread.
     */
    public synchronized boolean grabPixels(long ms)
        throws InterruptedException
    {
        if ((flags & DONEBITS) != 0) {
            return (flags & GRABBEDBITS) != 0;
        }
        long end = ms + System.currentTimeMillis();
        if (!grabbing) {
            grabbing = true;
            flags &= ~(ImageObserver.ABORT);
            producer.startProduction(this);
        }
        while (grabbing) {
            long timeout;
            if (ms == 0) {
                timeout = 0;
            } else {
                timeout = end - System.currentTimeMillis();
                if (timeout <= 0) {
                    break;
                }
            }
            wait(timeout);
        }
        return (flags & GRABBEDBITS) != 0;
    }

    
Return the status of the pixels.  The ImageObserver flags
representing the available pixel information are returned.

See Also:
Returns:the bitwise OR of all relevant ImageObserver flags
/**
     * Return the status of the pixels.  The ImageObserver flags
     * representing the available pixel information are returned.
     * @return the bitwise OR of all relevant ImageObserver flags
     * @see ImageObserver
     */
    public synchronized int getStatus() {
        return flags;
    }

    
Get the width of the pixel buffer (after adjusting for image width).
If no width was specified for the rectangle of pixels to grab then
then this information will only be available after the image has
delivered the dimensions.

See Also:
Returns:the final width used for the pixel buffer or -1 if the width
is not yet known
/**
     * Get the width of the pixel buffer (after adjusting for image width).
     * If no width was specified for the rectangle of pixels to grab then
     * then this information will only be available after the image has
     * delivered the dimensions.
     * @return the final width used for the pixel buffer or -1 if the width
     * is not yet known
     * @see #getStatus
     */
    public synchronized int getWidth() {
        return (dstW < 0) ? -1 : dstW;
    }

    
Get the height of the pixel buffer (after adjusting for image height).
If no width was specified for the rectangle of pixels to grab then
then this information will only be available after the image has
delivered the dimensions.

See Also:
Returns:the final height used for the pixel buffer or -1 if the height
is not yet known
/**
     * Get the height of the pixel buffer (after adjusting for image height).
     * If no width was specified for the rectangle of pixels to grab then
     * then this information will only be available after the image has
     * delivered the dimensions.
     * @return the final height used for the pixel buffer or -1 if the height
     * is not yet known
     * @see #getStatus
     */
    public synchronized int getHeight() {
        return (dstH < 0) ? -1 : dstH;
    }

    
Get the pixel buffer.  If the PixelGrabber was not constructed
with an explicit pixel buffer to hold the pixels then this method
will return null until the size and format of the image data is
known.
Since the PixelGrabber may fall back on accumulating the data
in the default RGB ColorModel at any time if the source image
uses more than one ColorModel to deliver the data, the array
object returned by this method may change over time until the
image grab is complete.

See Also:
Returns:either a byte array or an int array
/**
     * Get the pixel buffer.  If the PixelGrabber was not constructed
     * with an explicit pixel buffer to hold the pixels then this method
     * will return null until the size and format of the image data is
     * known.
     * Since the PixelGrabber may fall back on accumulating the data
     * in the default RGB ColorModel at any time if the source image
     * uses more than one ColorModel to deliver the data, the array
     * object returned by this method may change over time until the
     * image grab is complete.
     * @return either a byte array or an int array
     * @see #getStatus
     * @see #setPixels(int, int, int, int, ColorModel, byte[], int, int)
     * @see #setPixels(int, int, int, int, ColorModel, int[], int, int)
     */
    public synchronized Object getPixels() {
        return (bytePixels == null)
            ? ((Object) intPixels)
            : ((Object) bytePixels);
    }

    
Get the ColorModel for the pixels stored in the array.  If the
PixelGrabber was constructed with an explicit pixel buffer then
this method will always return the default RGB ColorModel,
otherwise it may return null until the ColorModel used by the
ImageProducer is known.
Since the PixelGrabber may fall back on accumulating the data
in the default RGB ColorModel at any time if the source image
uses more than one ColorModel to deliver the data, the ColorModel
object returned by this method may change over time until the
image grab is complete and may not reflect any of the ColorModel
objects that was used by the ImageProducer to deliver the pixels.

See Also:
Returns:the ColorModel object used for storing the pixels
/**
     * Get the ColorModel for the pixels stored in the array.  If the
     * PixelGrabber was constructed with an explicit pixel buffer then
     * this method will always return the default RGB ColorModel,
     * otherwise it may return null until the ColorModel used by the
     * ImageProducer is known.
     * Since the PixelGrabber may fall back on accumulating the data
     * in the default RGB ColorModel at any time if the source image
     * uses more than one ColorModel to deliver the data, the ColorModel
     * object returned by this method may change over time until the
     * image grab is complete and may not reflect any of the ColorModel
     * objects that was used by the ImageProducer to deliver the pixels.
     * @return the ColorModel object used for storing the pixels
     * @see #getStatus
     * @see ColorModel#getRGBdefault
     * @see #setColorModel(ColorModel)
     */
    public synchronized ColorModel getColorModel() {
        return imageModel;
    }

    
The setDimensions method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • width – the width of the dimension
  • height – the height of the dimension
/**
     * The setDimensions method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param width the width of the dimension
     * @param height the height of the dimension
     */
    public void setDimensions(int width, int height) {
        if (dstW < 0) {
            dstW = width - dstX;
        }
        if (dstH < 0) {
            dstH = height - dstY;
        }
        if (dstW <= 0 || dstH <= 0) {
            imageComplete(STATICIMAGEDONE);
        } else if (intPixels == null &&
                   imageModel == ColorModel.getRGBdefault()) {
            intPixels = new int[dstW * dstH];
            dstScan = dstW;
            dstOff = 0;
        }
        flags |= (ImageObserver.WIDTH | ImageObserver.HEIGHT);
    }

    
The setHints method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • hints – a set of hints used to process the pixels
/**
     * The setHints method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param hints a set of hints used to process the pixels
     */
    public void setHints(int hints) {
        return;
    }

    
The setProperties method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • props – the list of properties
/**
     * The setProperties method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param props the list of properties
     */
    public void setProperties(Hashtable<?,?> props) {
        return;
    }

    
The setColorModel method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • model – the specified ColorModel
See Also:
/**
     * The setColorModel method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param model the specified {@code ColorModel}
     * @see #getColorModel
     */
    public void setColorModel(ColorModel model) {
        return;
    }

    private void convertToRGB() {
        int size = dstW * dstH;
        int newpixels[] = new int[size];
        if (bytePixels != null) {
            for (int i = 0; i < size; i++) {
                newpixels[i] = imageModel.getRGB(bytePixels[i] & 0xff);
            }
        } else if (intPixels != null) {
            for (int i = 0; i < size; i++) {
                newpixels[i] = imageModel.getRGB(intPixels[i]);
            }
        }
        bytePixels = null;
        intPixels = newpixels;
        dstScan = dstW;
        dstOff = 0;
        imageModel = ColorModel.getRGBdefault();
    }

    
The setPixels method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • srcX – the X coordinate of the upper-left corner
       of the area of pixels to be set
  • srcY – the Y coordinate of the upper-left corner
       of the area of pixels to be set
  • srcW – the width of the area of pixels
  • srcH – the height of the area of pixels
  • model – the specified ColorModel
  • pixels – the array of pixels
  • srcOff – the offset into the pixels array
  • srcScan – the distance from one row of pixels to the next
       in the pixels array
See Also:
/**
     * The setPixels method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param srcX the X coordinate of the upper-left corner
     *        of the area of pixels to be set
     * @param srcY the Y coordinate of the upper-left corner
     *        of the area of pixels to be set
     * @param srcW the width of the area of pixels
     * @param srcH the height of the area of pixels
     * @param model the specified {@code ColorModel}
     * @param pixels the array of pixels
     * @param srcOff the offset into the pixels array
     * @param srcScan the distance from one row of pixels to the next
     *        in the pixels array
     * @see #getPixels
     */
    public void setPixels(int srcX, int srcY, int srcW, int srcH,
                          ColorModel model,
                          byte pixels[], int srcOff, int srcScan) {
        if (srcY < dstY) {
            int diff = dstY - srcY;
            if (diff >= srcH) {
                return;
            }
            srcOff += srcScan * diff;
            srcY += diff;
            srcH -= diff;
        }
        if (srcY + srcH > dstY + dstH) {
            srcH = (dstY + dstH) - srcY;
            if (srcH <= 0) {
                return;
            }
        }
        if (srcX < dstX) {
            int diff = dstX - srcX;
            if (diff >= srcW) {
                return;
            }
            srcOff += diff;
            srcX += diff;
            srcW -= diff;
        }
        if (srcX + srcW > dstX + dstW) {
            srcW = (dstX + dstW) - srcX;
            if (srcW <= 0) {
                return;
            }
        }
        int dstPtr = dstOff + (srcY - dstY) * dstScan + (srcX - dstX);
        if (intPixels == null) {
            if (bytePixels == null) {
                bytePixels = new byte[dstW * dstH];
                dstScan = dstW;
                dstOff = 0;
                imageModel = model;
            } else if (imageModel != model) {
                convertToRGB();
            }
            if (bytePixels != null) {
                for (int h = srcH; h > 0; h--) {
                    System.arraycopy(pixels, srcOff, bytePixels, dstPtr, srcW);
                    srcOff += srcScan;
                    dstPtr += dstScan;
                }
            }
        }
        if (intPixels != null) {
            int dstRem = dstScan - srcW;
            int srcRem = srcScan - srcW;
            for (int h = srcH; h > 0; h--) {
                for (int w = srcW; w > 0; w--) {
                    intPixels[dstPtr++] = model.getRGB(pixels[srcOff++]&0xff);
                }
                srcOff += srcRem;
                dstPtr += dstRem;
            }
        }
        flags |= ImageObserver.SOMEBITS;
    }

    
The setPixels method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • srcX – the X coordinate of the upper-left corner
       of the area of pixels to be set
  • srcY – the Y coordinate of the upper-left corner
       of the area of pixels to be set
  • srcW – the width of the area of pixels
  • srcH – the height of the area of pixels
  • model – the specified ColorModel
  • pixels – the array of pixels
  • srcOff – the offset into the pixels array
  • srcScan – the distance from one row of pixels to the next
       in the pixels array
See Also:
/**
     * The setPixels method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param srcX the X coordinate of the upper-left corner
     *        of the area of pixels to be set
     * @param srcY the Y coordinate of the upper-left corner
     *        of the area of pixels to be set
     * @param srcW the width of the area of pixels
     * @param srcH the height of the area of pixels
     * @param model the specified {@code ColorModel}
     * @param pixels the array of pixels
     * @param srcOff the offset into the pixels array
     * @param srcScan the distance from one row of pixels to the next
     *        in the pixels array
     * @see #getPixels
     */
    public void setPixels(int srcX, int srcY, int srcW, int srcH,
                          ColorModel model,
                          int pixels[], int srcOff, int srcScan) {
        if (srcY < dstY) {
            int diff = dstY - srcY;
            if (diff >= srcH) {
                return;
            }
            srcOff += srcScan * diff;
            srcY += diff;
            srcH -= diff;
        }
        if (srcY + srcH > dstY + dstH) {
            srcH = (dstY + dstH) - srcY;
            if (srcH <= 0) {
                return;
            }
        }
        if (srcX < dstX) {
            int diff = dstX - srcX;
            if (diff >= srcW) {
                return;
            }
            srcOff += diff;
            srcX += diff;
            srcW -= diff;
        }
        if (srcX + srcW > dstX + dstW) {
            srcW = (dstX + dstW) - srcX;
            if (srcW <= 0) {
                return;
            }
        }
        if (intPixels == null) {
            if (bytePixels == null) {
                intPixels = new int[dstW * dstH];
                dstScan = dstW;
                dstOff = 0;
                imageModel = model;
            } else {
                convertToRGB();
            }
        }
        int dstPtr = dstOff + (srcY - dstY) * dstScan + (srcX - dstX);
        if (imageModel == model) {
            for (int h = srcH; h > 0; h--) {
                System.arraycopy(pixels, srcOff, intPixels, dstPtr, srcW);
                srcOff += srcScan;
                dstPtr += dstScan;
            }
        } else {
            if (imageModel != ColorModel.getRGBdefault()) {
                convertToRGB();
            }
            int dstRem = dstScan - srcW;
            int srcRem = srcScan - srcW;
            for (int h = srcH; h > 0; h--) {
                for (int w = srcW; w > 0; w--) {
                    intPixels[dstPtr++] = model.getRGB(pixels[srcOff++]);
                }
                srcOff += srcRem;
                dstPtr += dstRem;
            }
        }
        flags |= ImageObserver.SOMEBITS;
    }

    
The imageComplete method is part of the ImageConsumer API which
this class must implement to retrieve the pixels.


Note: This method is intended to be called by the ImageProducer
of the Image whose pixels are being grabbed.  Developers using
this class to retrieve pixels from an image should avoid calling
this method directly since that operation could result in problems
with retrieving the requested pixels.

Params:
  • status – the status of image loading
/**
     * The imageComplete method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     * <p>
     * Note: This method is intended to be called by the ImageProducer
     * of the Image whose pixels are being grabbed.  Developers using
     * this class to retrieve pixels from an image should avoid calling
     * this method directly since that operation could result in problems
     * with retrieving the requested pixels.
     * @param status the status of image loading
     */
    public synchronized void imageComplete(int status) {
        grabbing = false;
        switch (status) {
        default:
        case IMAGEERROR:
            flags |= ImageObserver.ERROR | ImageObserver.ABORT;
            break;
        case IMAGEABORTED:
            flags |= ImageObserver.ABORT;
            break;
        case STATICIMAGEDONE:
            flags |= ImageObserver.ALLBITS;
            break;
        case SINGLEFRAMEDONE:
            flags |= ImageObserver.FRAMEBITS;
            break;
        }
        producer.removeConsumer(this);
        notifyAll();
    }

    
Returns the status of the pixels. The ImageObserver flags representing the available pixel information are returned. This method and getStatus have the same implementation, but getStatus is the preferred method because it conforms to the convention of naming information-retrieval methods with the form "getXXX". 
See Also:
Returns:the bitwise OR of all relevant ImageObserver flags
/**
     * Returns the status of the pixels.  The ImageObserver flags
     * representing the available pixel information are returned.
     * This method and {@link #getStatus() getStatus} have the
     * same implementation, but {@code getStatus} is the
     * preferred method because it conforms to the convention of
     * naming information-retrieval methods with the form
     * "getXXX".
     * @return the bitwise OR of all relevant ImageObserver flags
     * @see ImageObserver
     * @see #getStatus()
     */
    public synchronized int status() {
        return flags;
    }
}