/* * @(#)PNGImageDecoder.java 1.17 06/10/10 * * Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER * * This program 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. * * This program 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 at /legal/license.txt). * * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.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 <a href=ftp://ds.internic.net/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; // 4679080 - create instance of properties as in JPEG and GIF image architecture. private Hashtable properties = new Hashtable(); /* this is not needed ImageConsumer target; */ private ColorModel cm; private byte[] red_map, green_map, blue_map, alpha_map; private int transparentPixel = -1; private static ColorModel greyModels[] = new ColorModel[4]; /* this is not needed PNGImageDecoder next; */ private void property(String key, Object value) { if (value == null) return; properties.put(key, value); } private void property(String key, float value) { property(key, new Float(value)); } private final void verify(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: verify(len == 6); c = new Color(buf[st] & 0xff, buf[st + 2] & 0xff, buf[st + 4] & 0xff); break; case COLOR | PALETTE: case COLOR | PALETTE | ALPHA: verify(len == 1); int ix = buf[st] & 0xFF; verify(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: verify(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 verify(len == 6); transparentPixel = ((buf[st + 0] & 0xFF) << 16) | ((buf[st + 2] & 0xFF) << 8) | ((buf[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 verify(len == 2); int t = buf[st] & 0xFF; transparentPixel = (t << 16) | (t << 8) | t; break; } break; case zTXtChunk: break; } return true; } 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)); cm = new IndexColorModel(bitDepth, ramp.length, ramp, ramp, ramp); 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); // 4679080 - set properties as in JPEG and GIF image architecture. setProperties(properties); // end fix - 4679080 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 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; 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): wPixels[col + rowOffset] = ((rowByteBuffer[spos ] & 0xFF) << 16) | ((rowByteBuffer[spos + 1] & 0xFF) << 8) | ((rowByteBuffer[spos + 2] & 0xFF)) | ((0xFF) << 24); spos += 3; break; case COLOR | (16 << 3): wPixels[col + rowOffset] = ((rowByteBuffer[spos ] & 0xFF) << 16) | ((rowByteBuffer[spos + 2] & 0xFF) << 8) | ((rowByteBuffer[spos + 4] & 0xFF)) | ((0xFF) << 24); 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)) & 7); 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 (Throwable e) { /* 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); // } e.printStackTrace(); } 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; 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 synchronized static void waitTurn() { try { while(ThreadLimit<=0) PNGImageDecoder.class.wait(1000); } catch(InterruptedException e){} ThreadLimit--; } private synchronized static 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 final int getInt(int pos) { return ((inbuf[pos ] & 0xFF) << 24) | ((inbuf[pos + 1] & 0xFF) << 16) | ((inbuf[pos + 2] & 0xFF) << 8) | ((inbuf[pos + 3] & 0xFF)); } private final int getShort(int pos) { return (short) (((inbuf[pos ] & 0xFF) << 8) | ((inbuf[pos + 1] & 0xFF))); } private final int getByte(int pos) { return inbuf[pos] & 0xFF; } private final 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)). */ static private 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]. */ static private 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; } }