-
PNGImageDecoder
-
GRAY: int
-
PALETTE: int
-
COLOR: int
-
ALPHA: int
-
bKGDChunk: int
-
cHRMChunk: int
-
gAMAChunk: int
-
hISTChunk: int
-
IDATChunk: int
-
IENDChunk: int
-
IHDRChunk: int
-
PLTEChunk: int
-
pHYsChunk: int
-
sBITChunk: int
-
tEXtChunk: int
-
tIMEChunk: int
-
tRNSChunk: int
-
zTXtChunk: int
-
width: int
-
height: int
-
bitDepth: int
-
colorType: int
-
compressionMethod: int
-
filterMethod: int
-
interlaceMethod: int
-
gamma: int
-
properties: Hashtable<String, Object>
-
cm: ColorModel
-
red_map: byte[]
-
green_map: byte[]
-
blue_map: byte[]
-
alpha_map: byte[]
-
transparentPixel: int
-
transparentPixel_16: byte[]
-
greyModels: ColorModel[]
-
property(String, Object): void
-
property(String, float): void
-
pngassert(boolean): void
-
handleChunk(int, byte[], int, int): boolean
-
PNGException
-
produceImage(): void
-
sendPixels(int, int, int, int, int[], int, int): boolean
-
sendPixels(int, int, int, int, byte[], int, int): boolean
-
filterRow(byte[], byte[], int, int, int): void
-
startingRow: byte[]
-
startingCol: byte[]
-
rowIncrement: byte[]
-
colIncrement: byte[]
-
blockHeight: byte[]
-
blockWidth: byte[]
-
pos: int
-
limit: int
-
chunkStart: int
-
chunkKey: int
-
chunkLength: int
-
chunkCRC: int
-
seenEOF: boolean
-
signature: byte[]
-
inputStream: PNGFilterInputStream
-
underlyingInputStream: InputStream
-
PNGImageDecoder(InputStreamImageSource, InputStream): void
-
inbuf: byte[]
-
fill(): void
-
need(int): boolean
-
getInt(int): int
-
getShort(int): int
-
getByte(int): int
-
getChunk(): boolean
-
readAll(): void
-
getData(): boolean
-
checkCRC: boolean
-
getCheckCRC(): boolean
-
setCheckCRC(boolean): void
-
wrc(int): void
-
wrk(int): void
-
print(): void
-
crc_table: int[]
-
static class initializer
-
update_crc(int, byte[], int, int): int
-
crc(byte[], int, int): int
-
Chromaticities
-
-
PNGFilterInputStream
/*
* Copyright (c) 1999, 2018, 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 sun.awt.image;
import java.io.*;
import java.util.*;
import java.util.zip.*;
import java.awt.image.*;
import java.awt.Color;
PNG - Portable Network Graphics - image file reader.
See RFC2083 for details. /** PNG - Portable Network Graphics - image file reader.
See <a href=http://www.ietf.org/rfc/rfc2083.txt>RFC2083</a> for details. */
/* this is changed
public class PNGImageDecoder extends FilterInputStream implements Runnable
{ */
public class PNGImageDecoder extends ImageDecoder
{
private static final int GRAY=0;
private static final int PALETTE=1;
private static final int COLOR=2;
private static final int ALPHA=4;
private static final int bKGDChunk = 0x624B4744;
private static final int cHRMChunk = 0x6348524D;
private static final int gAMAChunk = 0x67414D41;
private static final int hISTChunk = 0x68495354;
private static final int IDATChunk = 0x49444154;
private static final int IENDChunk = 0x49454E44;
private static final int IHDRChunk = 0x49484452;
private static final int PLTEChunk = 0x504C5445;
private static final int pHYsChunk = 0x70485973;
private static final int sBITChunk = 0x73424954;
private static final int tEXtChunk = 0x74455874;
private static final int tIMEChunk = 0x74494D45;
private static final int tRNSChunk = 0x74524E53;
private static final int zTXtChunk = 0x7A545874;
private int width;
private int height;
private int bitDepth;
private int colorType;
private int compressionMethod;
private int filterMethod;
private int interlaceMethod;
private int gamma = 100000;
private java.util.Hashtable<String, Object> properties;
/* this is not needed
ImageConsumer target;
*/
private ColorModel cm;
private byte[] red_map, green_map, blue_map, alpha_map;
private int transparentPixel = -1;
private byte[] transparentPixel_16 = null; // we need 6 bytes to store 16bpp value
private static ColorModel[] greyModels = new ColorModel[4];
/* this is not needed
PNGImageDecoder next;
*/
private void property(String key,Object value) {
if(value==null) return;
if(properties==null) properties=new java.util.Hashtable<>();
properties.put(key,value);
}
private void property(String key,float value) {
property(key, Float.valueOf(value));
}
private void pngassert(boolean b) throws IOException {
if(!b) {
PNGException e = new PNGException("Broken file");
e.printStackTrace();
throw e;
}
}
protected boolean handleChunk(int key, byte[] buf, int st, int len)
throws IOException {
switch(key) {
case bKGDChunk:
Color c = null;
switch(colorType) {
case COLOR:
case COLOR|ALPHA:
pngassert(len==6);
c = new Color(buf[st]&0xff,buf[st+2]&0xff,buf[st+4]&0xff);
break;
case COLOR|PALETTE:
case COLOR|PALETTE|ALPHA:
pngassert(len==1);
int ix = buf[st]&0xFF;
pngassert(red_map!=null && ix<red_map.length);
c = new Color(red_map[ix]&0xff,green_map[ix]&0xff,blue_map[ix]&0xff);
break;
case GRAY:
case GRAY|ALPHA:
pngassert(len==2);
int t = buf[st]&0xFF;
c = new Color(t,t,t);
break;
}
if(c!=null) property("background",c);
break;
case cHRMChunk:
property("chromaticities",
new Chromaticities(
getInt(st),
getInt(st+4),
getInt(st+8),
getInt(st+12),
getInt(st+16),
getInt(st+20),
getInt(st+24),
getInt(st+28)));
break;
case gAMAChunk:
if(len!=4) throw new PNGException("bogus gAMA");
gamma = getInt(st);
if(gamma!=100000) property("gamma",gamma/100000.0f);
break;
case hISTChunk: break;
case IDATChunk: return false;
case IENDChunk: break;
case IHDRChunk:
if(len!=13
||(width = getInt(st))==0
||(height = getInt(st+4))==0
) throw new PNGException("bogus IHDR");
bitDepth = getByte(st+8);
colorType = getByte(st+9);
compressionMethod = getByte(st+10);
filterMethod = getByte(st+11);
interlaceMethod = getByte(st+12);
/* this is not needed
if(target!=null) target.setDimensions(width,height);
*/
break;
case PLTEChunk:
{ int tsize = len/3;
red_map = new byte[tsize];
green_map = new byte[tsize];
blue_map = new byte[tsize];
for(int i=0,j=st; i<tsize; i++, j+=3) {
red_map[i] = buf[j];
green_map[i] = buf[j+1];
blue_map[i] = buf[j+2];
}
}
break;
case pHYsChunk: break;
case sBITChunk: break;
case tEXtChunk:
int klen = 0;
while(klen<len && buf[st+klen]!=0) klen++;
if(klen<len) {
String tkey = new String(buf,st,klen);
String tvalue = new String(buf,st+klen+1,len-klen-1);
property(tkey,tvalue);
}
break;
case tIMEChunk:
property("modtime",new GregorianCalendar(
getShort(st+0),
getByte(st+2)-1,
getByte(st+3),
getByte(st+4),
getByte(st+5),
getByte(st+6)).getTime());
break;
case tRNSChunk:
switch(colorType) {
case PALETTE|COLOR:
case PALETTE|COLOR|ALPHA:
int alen = len;
if(red_map!=null) alen = red_map.length;
alpha_map = new byte[alen];
System.arraycopy(buf,st,alpha_map,0,len<alen ? len : alen);
while (--alen>=len) alpha_map[alen] = (byte)0xFF;
break;
case COLOR: // doesn't deal with 16 bit colors properly
case COLOR|ALPHA: // doesn't deal with 16 bit colors properly
pngassert(len==6);
if (bitDepth == 16) {
transparentPixel_16 = new byte[6];
for (int i = 0; i < 6; i++) {
transparentPixel_16[i] = (byte)getByte(st + i);
}
} else {
transparentPixel =
((getShort(st + 0)&0xFF)<<16)
| ((getShort(st + 2)&0xFF)<< 8)
| ((getShort(st + 4)&0xFF) );
}
break;
case GRAY: // doesn't deal with 16 bit colors properly
case GRAY|ALPHA: // doesn't deal with 16 bit colors properly
pngassert(len==2);
/* REMIND: Discarding the LSB for 16 bit depth here
* means that the all pixels which match the MSB
* will be treated as transparent.
*/
int t = getShort(st);
t = 0xFF & ((bitDepth == 16) ? (t >> 8) : t);
transparentPixel = (t<<16) | (t<< 8) | t;
break;
}
break;
case zTXtChunk: break;
}
return true;
}
@SuppressWarnings("serial") // JDK-implementation class
public class PNGException extends IOException {
PNGException(String s) { super(s); }
}
/* this is changed
public void run() {
*/
public void produceImage() throws IOException, ImageFormatException {
/* this is not needed
ImageConsumer t = target;
if(t!=null) try {
*/
try {
for(int i=0; i<signature.length; i++)
if((signature[i]&0xFF)!=underlyingInputStream.read())
throw new PNGException("Chunk signature mismatch");
InputStream is = new BufferedInputStream(new InflaterInputStream(inputStream,new Inflater()));
getData();
byte[] bPixels = null;
int[] wPixels = null;
int pixSize = width;
int rowStride;
int logDepth = 0;
switch(bitDepth) {
case 1: logDepth = 0; break;
case 2: logDepth = 1; break;
case 4: logDepth = 2; break;
case 8: logDepth = 3; break;
case 16: logDepth = 4; break;
default: throw new PNGException("invalid depth");
}
if(interlaceMethod!=0) {pixSize *= height;rowStride=width;}
else rowStride = 0;
int combinedType = colorType|(bitDepth<<3);
int bitMask = (1<<(bitDepth>=8?8:bitDepth))-1;
//Figure out the color model
switch(colorType) {
case COLOR|PALETTE:
case COLOR|PALETTE|ALPHA:
if(red_map==null) throw new PNGException("palette expected");
if(alpha_map==null)
cm = new IndexColorModel(bitDepth,red_map.length,
red_map,green_map,blue_map);
else
cm = new IndexColorModel(bitDepth,red_map.length,
red_map,green_map,blue_map,alpha_map);
bPixels = new byte[pixSize];
break;
case GRAY:
{ int llog = logDepth>=4 ? 3 : logDepth;
if((cm=greyModels[llog]) == null) {
int size = 1<<(1<<llog);
byte[] ramp = new byte[size];
for(int i = 0; i<size; i++) ramp[i] = (byte)(255*i/(size-1));
if (transparentPixel == -1) {
cm = new IndexColorModel(bitDepth,ramp.length,ramp,ramp,ramp);
} else {
cm = new IndexColorModel(bitDepth,ramp.length,ramp,ramp,ramp,
(transparentPixel & 0xFF));
}
greyModels[llog] = cm;
}
}
bPixels = new byte[pixSize];
break;
case COLOR:
case COLOR|ALPHA:
case GRAY|ALPHA:
cm = ColorModel.getRGBdefault();
wPixels = new int[pixSize];
break;
default:
throw new PNGException("invalid color type");
}
/* this is going to be set in the pixel store
t.setColorModel(cm);
t.setHints(interlaceMethod !=0
? ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES
: ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES |
ImageConsumer.SINGLEPASS | ImageConsumer.SINGLEFRAME);
*/
// code added to make it work with ImageDecoder architecture
setDimensions(width, height);
setColorModel(cm);
int flags = (interlaceMethod !=0
? ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES
: ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES |
ImageConsumer.SINGLEPASS | ImageConsumer.SINGLEFRAME);
setHints(flags);
headerComplete();
// end of adding
int samplesPerPixel = ((colorType&PALETTE)!=0 ? 1
: ((colorType&COLOR)!=0 ? 3 : 1)+((colorType&ALPHA)!=0?1:0));
int bitsPerPixel = samplesPerPixel*bitDepth;
int bytesPerPixel = (bitsPerPixel+7)>>3;
int pass, passLimit;
if(interlaceMethod==0) { pass = -1; passLimit = 0; }
else { pass = 0; passLimit = 7; }
// These loops are far from being tuned. They're this way to make them easy to
// debug. Tuning comes later.
/* code changed. target not needed here
while(++pass<=passLimit && (t=target)!=null) {
*/
while(++pass<=passLimit) {
int row = startingRow[pass];
int rowInc = rowIncrement[pass];
int colInc = colIncrement[pass];
int bWidth = blockWidth[pass];
int bHeight = blockHeight[pass];
int sCol = startingCol[pass];
int rowPixelWidth = (width-sCol+(colInc-1))/colInc;
int rowByteWidth = ((rowPixelWidth*bitsPerPixel)+7)>>3;
if(rowByteWidth==0) continue;
int pixelBufferInc = interlaceMethod==0 ? rowInc*width : 0;
int rowOffset = rowStride*row;
boolean firstRow = true;
byte[] rowByteBuffer = new byte[rowByteWidth];
byte[] prevRowByteBuffer = new byte[rowByteWidth];
/* code changed. target not needed here
while (row < height && (t=target)!=null) {
*/
while (row < height) {
int rowFilter = is.read();
for (int rowFillPos=0;rowFillPos<rowByteWidth; ) {
int n = is.read(rowByteBuffer,rowFillPos,rowByteWidth-rowFillPos);
if(n<=0) throw new PNGException("missing data");
rowFillPos+=n;
}
filterRow(rowByteBuffer,
firstRow ? null : prevRowByteBuffer,
rowFilter, rowByteWidth, bytesPerPixel);
int col = sCol;
int spos=0;
int pixel = 0;
while (col < width) {
if(wPixels !=null) {
switch(combinedType) {
case COLOR|ALPHA|(8<<3):
wPixels[col+rowOffset] =
((rowByteBuffer[spos ]&0xFF)<<16)
| ((rowByteBuffer[spos+1]&0xFF)<< 8)
| ((rowByteBuffer[spos+2]&0xFF) )
| ((rowByteBuffer[spos+3]&0xFF)<<24);
spos+=4;
break;
case COLOR|ALPHA|(16<<3):
wPixels[col+rowOffset] =
((rowByteBuffer[spos ]&0xFF)<<16)
| ((rowByteBuffer[spos+2]&0xFF)<< 8)
| ((rowByteBuffer[spos+4]&0xFF) )
| ((rowByteBuffer[spos+6]&0xFF)<<24);
spos+=8;
break;
case COLOR|(8<<3):
pixel =
((rowByteBuffer[spos ]&0xFF)<<16)
| ((rowByteBuffer[spos+1]&0xFF)<< 8)
| ((rowByteBuffer[spos+2]&0xFF) );
if (pixel != transparentPixel) {
pixel |= 0xff000000;
}
wPixels[col+rowOffset] = pixel;
spos+=3;
break;
case COLOR|(16<<3):
pixel =
((rowByteBuffer[spos ]&0xFF)<<16)
| ((rowByteBuffer[spos+2]&0xFF)<< 8)
| ((rowByteBuffer[spos+4]&0xFF) );
boolean isTransparent = (transparentPixel_16 != null);
for (int i = 0; isTransparent && (i < 6); i++) {
isTransparent &=
(rowByteBuffer[spos + i] & 0xFF) == (transparentPixel_16[i] & 0xFF);
}
if (!isTransparent) {
pixel |= 0xff000000;
}
wPixels[col+rowOffset] = pixel;
spos+=6;
break;
case GRAY|ALPHA|(8<<3):
{ int tx = rowByteBuffer[spos]&0xFF;
wPixels[col+rowOffset] =
(tx<<16)|(tx<<8)|tx
|((rowByteBuffer[spos+1]&0xFF)<<24); }
spos+=2;
break;
case GRAY|ALPHA|(16<<3):
{ int tx = rowByteBuffer[spos]&0xFF;
wPixels[col+rowOffset] =
(tx<<16)|(tx<<8)|tx
|((rowByteBuffer[spos+2]&0xFF)<<24); }
spos+=4;
break;
default: throw new PNGException("illegal type/depth");
}
} else switch(bitDepth) {
case 1:
bPixels[col+rowOffset] =
(byte)((rowByteBuffer[spos>>3]>>(7-(spos&7)))&1);
spos++;
break;
case 2:
bPixels[col+rowOffset] =
(byte)((rowByteBuffer[spos>>2]>>((3-(spos&3))*2))&3);
spos++;
break;
case 4:
bPixels[col+rowOffset] =
(byte)((rowByteBuffer[spos>>1]>>((1-(spos&1))*4))&15);
spos++;
break;
case 8: bPixels[col+rowOffset] = rowByteBuffer[spos++];
break;
case 16: bPixels[col+rowOffset] = rowByteBuffer[spos]; spos+=2;
break;
default: throw new PNGException("illegal type/depth");
}
/*visit (row, col,
min (bHeight, height - row),
min (bWidth, width - col)); */
col += colInc;
}
if(interlaceMethod==0)
if(wPixels!=null) {
/* code changed. target not needed here
t.setPixels(0,row,width,1,cm,wPixels,0,width);
*/
// code added to make it work with ImageDecoder arch
sendPixels(0,row,width,1,wPixels,0,width);
// end of adding
}
else {
/* code changed. target not needed here
t.setPixels(0,row,width,1,cm,bPixels,0,width);
*/
// code added to make it work with ImageDecoder arch
sendPixels(0,row,width,1,bPixels,0,width);
//end of adding
}
row += rowInc;
rowOffset += rowInc*rowStride;
byte[] T = rowByteBuffer;
rowByteBuffer = prevRowByteBuffer;
prevRowByteBuffer = T;
firstRow = false;
}
if(interlaceMethod!=0)
if(wPixels!=null) {
/* code changed. target not needed here
t.setPixels(0,0,width,height,cm,wPixels,0,width);
*/
// code added to make it work with ImageDecoder arch
sendPixels(0,0,width,height,wPixels,0,width);
//end of adding
}
else {
/* code changed. target not needed here
t.setPixels(0,0,width,height,cm,bPixels,0,width);
*/
// code added to make it work with ImageDecoder arch
sendPixels(0,0,width,height,bPixels,0,width);
//end of adding
}
}
/* Here, the function "visit(row,column,height,width)" obtains the
next transmitted pixel and paints a rectangle of the specified
height and width, whose upper-left corner is at the specified row
and column, using the color indicated by the pixel. Note that row
and column are measured from 0,0 at the upper left corner. */
/* code not needed, don't deal with target
if((t=target)!=null) {
if(properties!=null) t.setProperties(properties);
t.imageComplete(ImageConsumer.STATICIMAGEDONE);
*/
imageComplete(ImageConsumer.STATICIMAGEDONE, true);
/* code not needed }
is.close();
*/
} catch(IOException e) {
if(!aborted) {
/* code not needed
if((t=target)!=null) {
PNGEncoder.prChunk(e.toString(),inbuf,pos,limit-pos,true);
*/
property("error", e);
/* code not needed
t.setProperties(properties);
t.imageComplete(ImageConsumer.IMAGEERROR|ImageConsumer.STATICIMAGEDONE);
*/
imageComplete(ImageConsumer.IMAGEERROR|ImageConsumer.STATICIMAGEDONE, true);
throw e;
}
} finally {
try { close(); } catch(Throwable e){}
/* code not needed
target = null;
endTurn();
*/
}
}
private boolean sendPixels(int x, int y, int w, int h, int[] pixels,
int offset, int pixlength) {
int count = setPixels(x, y, w, h, cm,
pixels, offset, pixlength);
if (count <= 0) {
aborted = true;
}
return !aborted;
}
private boolean sendPixels(int x, int y, int w, int h, byte[] pixels,
int offset, int pixlength) {
int count = setPixels(x, y, w, h, cm,
pixels, offset, pixlength);
if (count <= 0) {
aborted = true;
}
return !aborted;
}
private void filterRow(byte[] rowByteBuffer, byte[] prevRow,
int rowFilter, int rowByteWidth, int bytesPerSample)
throws IOException {
int x = 0;
switch (rowFilter) {
case 0:
break;
case 1:
for (x = bytesPerSample; x < rowByteWidth; x++)
rowByteBuffer[x] += rowByteBuffer[x - bytesPerSample];
break;
case 2:
if (prevRow != null)
for ( ; x < rowByteWidth; x++)
rowByteBuffer[x] += prevRow[x];
break;
case 3:
if (prevRow != null) {
for ( ; x < bytesPerSample; x++)
rowByteBuffer[x] += (0xff & prevRow[x])>>1;
for ( ; x < rowByteWidth; x++)
rowByteBuffer[x] += ((prevRow[x]&0xFF) + (rowByteBuffer[x - bytesPerSample]&0xFF))>>1;
} else
for (x = bytesPerSample; x < rowByteWidth; x++)
rowByteBuffer[x] += (rowByteBuffer[x - bytesPerSample]&0xFF)>>1;
break;
case 4:
if (prevRow != null) {
for ( ; x < bytesPerSample; x++)
rowByteBuffer[x] += prevRow[x];
for ( ; x < rowByteWidth; x++) {
int a, b, c, p, pa, pb, pc, rval;
a = rowByteBuffer[x - bytesPerSample]&0xFF;
b = prevRow[x]&0xFF;
c = prevRow[x - bytesPerSample]&0xFF;
p = a + b - c;
pa = p > a ? p - a : a - p;
pb = p > b ? p - b : b - p;
pc = p > c ? p - c : c - p;
rowByteBuffer[x] += (pa <= pb) && (pa <= pc) ? a : pb <= pc ? b : c;
}
} else
for (x = bytesPerSample; x < rowByteWidth; x++)
rowByteBuffer[x] += rowByteBuffer[x - bytesPerSample];
break;
default:
throw new PNGException("Illegal filter");
}
}
private static final byte[] startingRow = { 0, 0, 0, 4, 0, 2, 0, 1 };
private static final byte[] startingCol = { 0, 0, 4, 0, 2, 0, 1, 0 };
private static final byte[] rowIncrement = { 1, 8, 8, 8, 4, 4, 2, 2 };
private static final byte[] colIncrement = { 1, 8, 8, 4, 4, 2, 2, 1 };
private static final byte[] blockHeight = { 1, 8, 8, 4, 4, 2, 2, 1 };
private static final byte[] blockWidth = { 1, 8, 4, 4, 2, 2, 1, 1 };
//abstract public class ChunkReader extends FilterInputStream {
int pos, limit;
int chunkStart;
int chunkKey, chunkLength, chunkCRC;
boolean seenEOF;
private static final byte[] signature = { (byte) 137, (byte) 80, (byte) 78,
(byte) 71, (byte) 13, (byte) 10, (byte) 26, (byte) 10 };
PNGFilterInputStream inputStream;
InputStream underlyingInputStream;
/* code changed
public PNGImageDecoder(InputStream in, ImageConsumer t) throws IOException {
*/
public PNGImageDecoder(InputStreamImageSource src, InputStream input) throws IOException {
// code added
super(src, input);
inputStream = new PNGFilterInputStream(this, input);
underlyingInputStream = inputStream.underlyingInputStream;
// end of adding
/* code changed
super(in);
target = t;
waitTurn();
new Thread(this).start();
*/
}
/* code changed to make it work with ImageDecoder architecture
static int ThreadLimit = 10;
private static synchronized void waitTurn() {
try {
while(ThreadLimit<=0) PNGImageDecoder.class.wait(1000);
} catch(InterruptedException e){}
ThreadLimit--;
}
private static synchronized void endTurn() {
if(ThreadLimit<=0) PNGImageDecoder.class.notify();
ThreadLimit++;
}
*/
byte[] inbuf = new byte[4096];
private void fill() throws IOException {
if(!seenEOF) {
if(pos>0 && pos<limit) {
System.arraycopy(inbuf,pos,inbuf,0,limit-pos);
limit = limit-pos;
pos = 0;
} else if(pos>=limit) {
pos = 0; limit = 0;
}
int bsize = inbuf.length;
while(limit<bsize) {
int n = underlyingInputStream.read(inbuf,limit,bsize-limit);
if(n<=0) { seenEOF=true; break; }
limit += n;
}
}
}
private boolean need(int n) throws IOException {
if(limit-pos>=n) return true;
fill();
if(limit-pos>=n) return true;
if(seenEOF) return false;
byte[] nin = new byte[n+100];
System.arraycopy(inbuf,pos,nin,0,limit-pos);
limit = limit-pos;
pos = 0;
inbuf = nin;
fill();
return limit-pos>=n;
}
private int getInt(int pos) {
return ((inbuf[pos ]&0xFF)<<24)
| ((inbuf[pos+1]&0xFF)<<16)
| ((inbuf[pos+2]&0xFF)<< 8)
| ((inbuf[pos+3]&0xFF) );
}
private int getShort(int pos) {
return (short)(((inbuf[pos ]&0xFF)<<8)
| ((inbuf[pos+1]&0xFF) ));
}
private int getByte(int pos) {
return inbuf[pos]&0xFF;
}
private boolean getChunk() throws IOException {
chunkLength = 0;
if (!need(8)) return false;
chunkLength = getInt(pos);
chunkKey = getInt(pos+4);
if(chunkLength<0) throw new PNGException("bogus length: "+chunkLength);
if (!need(chunkLength+12)) return false;
chunkCRC = getInt(pos+8+chunkLength);
chunkStart = pos+8;
int calcCRC = crc(inbuf,pos+4,chunkLength+4);
if(chunkCRC!=calcCRC && checkCRC) throw new PNGException("crc corruption");
pos+=chunkLength+12;
return true;
}
private void readAll() throws IOException {
while(getChunk()) handleChunk(chunkKey,inbuf,chunkStart,chunkLength);
}
boolean getData() throws IOException {
while(chunkLength==0 && getChunk())
if(handleChunk(chunkKey,inbuf,chunkStart,chunkLength))
chunkLength = 0;
return chunkLength>0;
}
//abstract protected boolean handleChunk(int key, byte[] buf, int st, int len)
// throws IOException;
private static boolean checkCRC = true;
public static boolean getCheckCRC() { return checkCRC; }
public static void setCheckCRC(boolean c) { checkCRC = c; }
protected void wrc(int c) {
c = c&0xFF;
if(c<=' '||c>'z') c = '?';
System.out.write(c);
}
protected void wrk(int n) {
wrc(n>>24);
wrc(n>>16);
wrc(n>>8);
wrc(n);
}
public void print() {
wrk(chunkKey);
System.out.print(" "+chunkLength+"\n");
}
/* Table of CRCs of all 8-bit messages. */
private static final int[] crc_table = new int[256];
/* Make the table for a fast CRC. */
static {
for (int n = 0; n < 256; n++) {
int c = n;
for (int k = 0; k < 8; k++)
if ((c & 1) != 0)
c = 0xedb88320 ^ (c >>> 1);
else
c = c >>> 1;
crc_table[n] = c;
}
}
/* Update a running CRC with the bytes buf[0..len-1]--the CRC
should be initialized to all 1's, and the transmitted value
is the 1's complement of the final running CRC (see the
crc() routine below)). */
private static int update_crc(int crc, byte[] buf, int offset, int len) {
int c = crc;
while (--len>=0)
c = crc_table[(c ^ buf[offset++]) & 0xff] ^ (c >>> 8);
return c;
}
/* Return the CRC of the bytes buf[0..len-1]. */
private static int crc(byte[] buf, int offset, int len) {
return update_crc(0xffffffff, buf, offset, len) ^ 0xffffffff;
}
public static class Chromaticities {
public float whiteX, whiteY, redX, redY, greenX, greenY, blueX, blueY;
Chromaticities(int wx, int wy, int rx, int ry, int gx, int gy, int bx, int by) {
whiteX = wx/100000.0f;
whiteY = wy/100000.0f;
redX = rx/100000.0f;
redY = ry/100000.0f;
greenX = gx/100000.0f;
greenY = gy/100000.0f;
blueX = bx/100000.0f;
blueY = by/100000.0f;
}
public String toString() {
return "Chromaticities(white="+whiteX+","+whiteY+";red="+
redX+","+redY+";green="+
greenX+","+greenY+";blue="+
blueX+","+blueY+")";
}
}
}
// the following class are added to make it work with ImageDecoder architecture
class PNGFilterInputStream extends FilterInputStream {
PNGImageDecoder owner;
public InputStream underlyingInputStream;
public PNGFilterInputStream(PNGImageDecoder owner, InputStream is) {
super(is);
underlyingInputStream = in;
this.owner = owner;
}
public int available() throws IOException {
return owner.limit-owner.pos+in.available();}
public boolean markSupported() { return false; }
public int read() throws IOException {
if(owner.chunkLength<=0) if(!owner.getData()) return -1;
owner.chunkLength--;
return owner.inbuf[owner.chunkStart++]&0xFF;
}
public int read(byte[] b) throws IOException{return read(b,0,b.length);}
public int read(byte[] b, int st, int len) throws IOException {
if(owner.chunkLength<=0) if(!owner.getData()) return -1;
if(owner.chunkLength<len) len = owner.chunkLength;
System.arraycopy(owner.inbuf,owner.chunkStart,b,st,len);
owner.chunkLength-=len;
owner.chunkStart+=len;
return len;
}
public long skip(long n) throws IOException {
int i;
for(i = 0; i<n && read()>=0; i++);
return i;
}
}