+/*
+ * This file was adapted from Jason Marshall's PNGImageProducer.java
+ *
+ * Copyright (c) 1997, Jason Marshall. All Rights Reserved
+ *
+ * The author makes no representations or warranties regarding the suitability,
+ * reliability or stability of this code. This code is provided AS IS. The
+ * author shall not be liable for any damages suffered as a result of using,
+ * modifying or redistributing this software or any derivitives thereof.
+ * Permission to use, reproduce, modify and/or (re)distribute this software is
+ * hereby granted.
+ */
+
+package org.ibex.translators;
+
+import org.ibex.*;
+import org.ibex.util.*;
+import java.io.*;
+import java.util.Hashtable;
+import java.util.Vector;
+import java.util.Enumeration;
+import java.util.zip.*;
+
+/** Converts an InputStream carrying a PNG image into an ARGB int[] */
+public class PNG {
+
+ public PNG() { }
+
+ private static Queue instances = new Queue(10);
+ private Picture p;
+
+ public static void load(InputStream is, Picture p) {
+ PNG g = (PNG)instances.remove(false);
+ if (g == null) g = new PNG();
+ try {
+ g._load(is, p);
+ p.data = g.data;
+ } catch (Exception e) {
+ if (Log.on) Log.info(PNG.class, e);
+ return;
+ }
+ // FIXME: must reset fields
+ // if (instances.size() < 10) instances.append(g);
+ }
+
+ // Public Methods ///////////////////////////////////////////////////////////////////////////////
+
+ /** process a PNG as an inputstream; returns null if there is an error
+ @param name A string describing the image, to be used when logging errors
+ */
+ private void _load(InputStream is, Picture pic) throws IOException {
+ p = pic;
+ if (is instanceof BufferedInputStream) underlyingStream = (BufferedInputStream)is;
+ else underlyingStream = new BufferedInputStream(is);
+ target_offset = 0;
+ inputStream = new DataInputStream(underlyingStream);
+
+ // consume the header
+ if ((inputStream.read() != 137) || (inputStream.read() != 80) || (inputStream.read() != 78) || (inputStream.read() != 71) ||
+ (inputStream.read() != 13) || (inputStream.read() != 10) || (inputStream.read() != 26) || (inputStream.read() != 10)) {
+ Log.info(this, "PNG: error: input file is not a PNG file");
+ data = p.data = new int[] { };
+ p.width = p.height = 0;
+ return;
+ }
+
+
+ while (!error) {
+ if (needChunkInfo) {
+ chunkLength = inputStream.readInt();
+ chunkType = inputStream.readInt();
+ needChunkInfo = false;
+ }
+
+ // I rewrote this as an if/else to work around a JODE bug with switch() blocks
+ if (chunkType == CHUNK_bKGD) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_cHRM) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_gAMA) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_hIST) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_pHYs) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_sBIT) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_tEXt) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_zTXt) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_tIME) inputStream.skip(chunkLength);
+ else if (chunkType == CHUNK_IHDR) handleIHDR();
+ else if (chunkType == CHUNK_PLTE) handlePLTE();
+ else if (chunkType == CHUNK_tRNS) handletRNS();
+ else if (chunkType == CHUNK_IDAT) handleIDAT();
+ else if (chunkType == CHUNK_IEND) break;
+ else {
+ System.err.println("unrecognized chunk type " + Integer.toHexString(chunkType) + ". skipping");
+ inputStream.skip(chunkLength);
+ }
+
+ int crc = inputStream.readInt();
+ needChunkInfo = true;
+ }
+ p.isLoaded = true;
+ }
+
+ // Chunk Handlers ///////////////////////////////////////////////////////////////////////
+
+ /** handle data chunk */
+ private void handleIDAT() throws IOException {
+ if (p.width == -1 || p.height == -1) throw new IOException("never got image width/height");
+ switch (depth) {
+ case 1: mask = 0x1; break;
+ case 2: mask = 0x3; break;
+ case 4: mask = 0xf; break;
+ case 8: case 16: mask = 0xff; break;
+ default: mask = 0x0; break;
+ }
+ if (depth < 8) smask = mask << depth;
+ else smask = mask << 8;
+
+ int count = p.width * p.height;
+
+ switch (colorType) {
+ case 0:
+ case 2:
+ case 6:
+ case 4:
+ ipixels = new int[count];
+ pixels = ipixels;
+ break;
+ case 3:
+ bpixels = new byte[count];
+ pixels = bpixels;
+ break;
+ default:
+ throw new IOException("Image has unknown color type");
+ }
+ if (interlaceMethod != 0) multipass = true;
+ readImageData();
+ }
+
+ /** handle header chunk */
+ private void handleIHDR() throws IOException {
+ if (headerFound) throw new IOException("Extraneous IHDR chunk encountered.");
+ if (chunkLength != 13) throw new IOException("IHDR chunk length wrong: " + chunkLength);
+ p.width = inputStream.readInt();
+ p.height = inputStream.readInt();
+ depth = inputStream.read();
+ colorType = inputStream.read();
+ compressionMethod = inputStream.read();
+ filterMethod = inputStream.read();
+ interlaceMethod = inputStream.read();
+ }
+
+ /** handle pallette chunk */
+ private void handlePLTE() throws IOException {
+ if (colorType == 3) {
+ palette = new byte[chunkLength];
+ inputStream.readFully(palette);
+ } else {
+ // Ignore suggested palette
+ inputStream.skip(chunkLength);
+ }
+ }
+
+ /** handle transparency chunk; modifies palette */
+ private void handletRNS() throws IOException {
+ int chunkLen = chunkLength;
+ if (palette == null) {
+ if (Log.on) Log.info(this, "warning: tRNS chunk encountered before pLTE; ignoring alpha channel");
+ inputStream.skip(chunkLength);
+ return;
+ }
+ int len = palette.length;
+ if (colorType == 3) {
+ transparency = true;
+
+ int transLength = len/3;
+ byte[] trans = new byte[transLength];
+ for (int i = 0; i < transLength; i++) trans[i] = (byte) 0xff;
+ inputStream.readFully(trans, 0, chunkLength);
+
+ byte[] newPalette = new byte[len + transLength];
+ for (int i = newPalette.length; i > 0;) {
+ newPalette[--i] = trans[--transLength];
+ newPalette[--i] = palette[--len];
+ newPalette[--i] = palette[--len];
+ newPalette[--i] = palette[--len];
+ }
+ palette = newPalette;
+
+ } else {
+ inputStream.skip(chunkLength);
+ }
+ }
+
+ /// Helper functions for IDAT ///////////////////////////////////////////////////////////////////////////////////////////
+
+ /** Read Image data in off of a compression stream */
+ private void readImageData() throws IOException {
+ InputStream dataStream = new SequenceInputStream(new IDATEnumeration(this));
+ DataInputStream dis = new DataInputStream(new BufferedInputStream(new InflaterInputStream(dataStream, new Inflater())));
+ int bps, filterOffset;
+ switch (colorType) {
+ case 0: case 3: bps = depth; break;
+ case 2: bps = 3 * depth; break;
+ case 4: bps = depth<<1; break;
+ case 6: bps = depth<<2; break;
+ default: throw new IOException("Unknown color type encountered.");
+ }
+
+ filterOffset = (bps + 7) >> 3;
+
+ for (pass = (multipass ? 1 : 0); pass < 8; pass++) {
+ int pass = this.pass;
+ int rInc = rowInc[pass];
+ int cInc = colInc[pass];
+ int sCol = startingCol[pass];
+ int val = (p.width - sCol + cInc - 1) / cInc;
+ int samples = val * filterOffset;
+ int rowSize = (val * bps)>>3;
+ int sRow = startingRow[pass];
+ if (p.height <= sRow || rowSize == 0) continue;
+ int sInc = rInc * p.width;
+ byte inbuf[] = new byte[rowSize];
+ int pix[] = new int[rowSize];
+ int upix[] = null;
+ int temp[] = new int[rowSize];
+ int nextY = sRow; // next Y value and number of rows to report to sendPixels
+ int rows = 0;
+ int rowStart = sRow * p.width;
+
+ for (int y = sRow; y < p.height; y += rInc, rowStart += sInc) {
+ rows += rInc;
+ int rowFilter = dis.read();
+ dis.readFully(inbuf);
+ if (!filterRow(inbuf, pix, upix, rowFilter, filterOffset)) throw new IOException("Unknown filter type: " + rowFilter);
+ insertPixels(pix, rowStart + sCol, samples);
+ if (multipass && (pass < 6)) blockFill(rowStart);
+ upix = pix;
+ pix = temp;
+ temp = upix;
+ }
+ if (!multipass) break;
+ }
+ while(dis.read() != -1) System.err.println("Leftover data encountered.");
+
+ // 24-bit color is our native format
+ if (colorType == 2 || colorType == 6) {
+ data = (int[])pixels;
+ if (colorType == 2) {
+ for(int i=0; i<data.length; i++)
+ data[i] |= 0xFF000000;
+ }
+
+ } else if (colorType == 3) {
+ byte[] pix = (byte[])pixels;
+ data = new int[pix.length];
+ for(int i=0; i<pix.length; i++) {
+ if (transparency) {
+ data[i] =
+ ((palette[4 * (pix[i] & 0xff) + 3] & 0xff) << 24) |
+ ((palette[4 * (pix[i] & 0xff) + 0] & 0xff) << 16) |
+ ((palette[4 * (pix[i] & 0xff) + 1] & 0xff) << 8) |
+ (palette[4 * (pix[i] & 0xff) + 2] & 0xff);
+ } else {
+ data[i] =
+ 0xFF000000 |
+ ((palette[3 * (pix[i] & 0xff) + 0] & 0xff) << 16) |
+ ((palette[3 * (pix[i] & 0xff) + 1] & 0xff) << 8) |
+ (palette[3 * (pix[i] & 0xff) + 2] & 0xff);
+ }
+ }
+
+ } else if (colorType == 0 || colorType == 4) {
+ if (depth == 16) depth = 8;
+ int[] pix = (int[])pixels;
+ data = new int[pix.length];
+ for(int i=0; i<pix.length; i ++) {
+ if (colorType == 0) {
+ int val = (pix[i] & 0xff) << (8 - depth);
+ data[i] =
+ 0xFF000000 |
+ (val << 16) |
+ (val << 8) |
+ val;
+ } else {
+ int alpha = (pix[i] & mask) << (8 - depth);
+ int val = ((pix[i] & smask) >> depth) << (8 - depth);
+ data[i] =
+ (alpha << 24) |
+ (val << 16) |
+ (val << 8) |
+ val;
+ }
+ }
+ }
+
+ }
+
+ private void insertGreyPixels(int pix[], int offset, int samples) {
+ int p = pix[0];
+ int ipix[] = ipixels;
+ int cInc = colInc[pass];
+ int rs = 0;
+
+ if (colorType == 0) {
+ switch (depth) {
+ case 1:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs--;
+ else { rs = 7; p = pix[j>>3]; }
+ ipix[offset] = (p>>rs) & 0x1;
+ }
+ break;
+ case 2:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs -= 2;
+ else { rs = 6; p = pix[j>>2]; }
+ ipix[offset] = (p>>rs) & 0x3;
+ }
+ break;
+ case 4:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs = 0;
+ else { rs = 4; p = pix[j>>1]; }
+ ipix[offset] = (p>>rs) & 0xf;
+ }
+ break;
+ case 8:
+ for (int j = 0; j < samples; offset += cInc) ipix[offset] = (byte) pix[j++];
+ break;
+ case 16:
+ samples = samples<<1;
+ for (int j = 0; j < samples; j += 2, offset += cInc) ipix[offset] = pix[j];
+ break;
+ default: break;
+ }
+ } else if (colorType == 4) {
+ if (depth == 8) {
+ for (int j = 0; j < samples; offset += cInc) ipix[offset] = (pix[j++]<<8) | pix[j++];
+ } else {
+ samples = samples<<1;
+ for (int j = 0; j < samples; j += 2, offset += cInc) ipix[offset] = (pix[j]<<8) | pix[j+=2];
+ }
+ }
+ }
+
+ private void insertPalettedPixels(int pix[], int offset, int samples) {
+ int rs = 0;
+ int p = pix[0];
+ byte bpix[] = bpixels;
+ int cInc = colInc[pass];
+
+ switch (depth) {
+ case 1:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs--;
+ else { rs = 7; p = pix[j>>3]; }
+ bpix[offset] = (byte) ((p>>rs) & 0x1);
+ }
+ break;
+ case 2:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs -= 2;
+ else { rs = 6; p = pix[j>>2]; }
+ bpix[offset] = (byte) ((p>>rs) & 0x3);
+ }
+ break;
+ case 4:
+ for (int j = 0; j < samples; j++, offset += cInc) {
+ if (rs != 0) rs = 0;
+ else { rs = 4; p = pix[j>>1]; }
+ bpix[offset] = (byte) ((p>>rs) & 0xf);
+ }
+ break;
+ case 8:
+ for (int j = 0; j < samples; j++, offset += cInc) bpix[offset] = (byte) pix[j];
+ break;
+ }
+ }
+
+ private void insertPixels(int pix[], int offset, int samples) {
+ switch (colorType) {
+ case 0:
+ case 4:
+ insertGreyPixels(pix, offset, samples);
+ break;
+ case 2: {
+ int j = 0;
+ int ipix[] = ipixels;
+ int cInc = colInc[pass];
+ if (depth == 8) {
+ for (j = 0; j < samples; offset += cInc)
+ ipix[offset] = (pix[j++]<<16) | (pix[j++]<<8) | pix[j++];
+ } else {
+ samples = samples<<1;
+ for (j = 0; j < samples; j += 2, offset += cInc)
+ ipix[offset] = (pix[j]<<16) | (pix[j+=2]<<8) | pix[j+=2];
+ }
+ break; }
+ case 3:
+ insertPalettedPixels(pix, offset, samples);
+ break;
+ case 6: {
+ int j = 0;
+ int ipix[] = ipixels;
+ int cInc = colInc[pass];
+ if (depth == 8) {
+ for (j = 0; j < samples; offset += cInc) {
+ ipix[offset] = (pix[j++]<<16) | (pix[j++]<<8) | pix[j++] |
+ (pix[j++]<<24);
+ }
+ } else {
+ samples = samples<<1;
+ for (j = 0; j < samples; j += 2, offset += cInc) {
+ ipix[offset] = (pix[j]<<16) | (pix[j+=2]<<8) | pix[j+=2] |
+ (pix[j+=2]<<24);
+ }
+ }
+ break; }
+ default:
+ break;
+ }
+ }
+
+ private void blockFill(int rowStart) {
+ int counter;
+ int dw = p.width;
+ int pass = this.pass;
+ int w = blockWidth[pass];
+ int sCol = startingCol[pass];
+ int cInc = colInc[pass];
+ int wInc = cInc - w;
+ int maxW = rowStart + dw - w;
+ int len;
+ int h = blockHeight[pass];
+ int maxH = rowStart + (dw * h);
+ int startPos = rowStart + sCol;
+ counter = startPos;
+
+ if (colorType == 3) {
+ byte bpix[] = bpixels;
+ byte pixel;
+ len = bpix.length;
+ for (; counter <= maxW;) {
+ int end = counter + w;
+ pixel = bpix[counter++];
+ for (; counter < end; counter++) bpix[counter] = pixel;
+ counter += wInc;
+ }
+ maxW += w;
+ if (counter < maxW)
+ for (pixel = bpix[counter++]; counter < maxW; counter++)
+ bpix[counter] = pixel;
+ if (len < maxH) maxH = len;
+ for (counter = startPos + dw; counter < maxH; counter += dw)
+ System.arraycopy(bpix, startPos, bpix, counter, dw - sCol);
+ } else {
+ int ipix[] = ipixels;
+ int pixel;
+ len = ipix.length;
+ for (; counter <= maxW;) {
+ int end = counter + w;
+ pixel = ipix[counter++];
+ for (; counter < end; counter++)
+ ipix[counter] = pixel;
+ counter += wInc;
+ }
+ maxW += w;
+ if (counter < maxW)
+ for (pixel = ipix[counter++]; counter < maxW; counter++)
+ ipix[counter] = pixel;
+ if (len < maxH) maxH = len;
+ for (counter = startPos + dw; counter < maxH; counter += dw)
+ System.arraycopy(ipix, startPos, ipix, counter, dw - sCol);
+ }
+ }
+
+ private boolean filterRow(byte inbuf[], int pix[], int upix[], int rowFilter, int boff) {
+ int rowWidth = pix.length;
+ switch (rowFilter) {
+ case 0: {
+ for (int x = 0; x < rowWidth; x++) pix[x] = 0xff & inbuf[x];
+ break; }
+ case 1: {
+ int x = 0;
+ for ( ; x < boff; x++) pix[x] = 0xff & inbuf[x];
+ for ( ; x < rowWidth; x++) pix[x] = 0xff & (inbuf[x] + pix[x - boff]);
+ break; }
+ case 2: {
+ if (upix != null) {
+ for (int x = 0; x < rowWidth; x++)
+ pix[x] = 0xff & (upix[x] + inbuf[x]);
+ } else {
+ for (int x = 0; x < rowWidth; x++)
+ pix[x] = 0xff & inbuf[x];
+ }
+ break; }
+ case 3: {
+ if (upix != null) {
+ int x = 0;
+ for ( ; x < boff; x++) {
+ int rval = upix[x];
+ pix[x] = 0xff & ((rval>>1) + inbuf[x]);
+ }
+ for ( ; x < rowWidth; x++) {
+ int rval = upix[x] + pix[x - boff];
+ pix[x] = 0xff & ((rval>>1) + inbuf[x]);
+ }
+ } else {
+ int x = 0;
+ for ( ; x < boff; x++) pix[x] = 0xff & inbuf[x];
+ for ( ; x < rowWidth; x++) {
+ int rval = pix[x - boff];
+ pix[x] = 0xff & ((rval>>1) + inbuf[x]);
+ }
+ }
+ break; }
+ case 4: {
+ if (upix != null) {
+ int x = 0;
+ for ( ; x < boff; x++) pix[x] = 0xff & (upix[x] + inbuf[x]);
+ for ( ; x < rowWidth; x++) {
+ int a, b, c, p, pa, pb, pc, rval;
+ a = pix[x - boff];
+ b = upix[x];
+ c = upix[x - boff];
+ 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;
+ if ((pa <= pb) && (pa <= pc)) rval = a;
+ else if (pb <= pc) rval = b;
+ else rval = c;
+ pix[x] = 0xff & (rval + inbuf[x]);
+ }
+ } else {
+ int x = 0;
+ for ( ; x < boff; x++) pix[x] = 0xff & inbuf[x];
+ for ( ; x < rowWidth; x++) {
+ int rval = pix[x - boff];
+ pix[x] = 0xff & (rval + inbuf[x]);
+ }
+ }
+ break; }
+ default: return false;
+ }
+ return true;
+ }
+
+ // Private Data ///////////////////////////////////////////////////////////////////////////////////////
+
+ private int target_offset = 0;
+ private int sigmask = 0xffff;
+ private Object pixels = null;
+ private int ipixels[] = null;
+ private byte bpixels[] = null;
+ private boolean multipass = false;
+ private boolean complete = false;
+ private boolean error = false;
+
+ int[] data = null;
+
+ private InputStream underlyingStream = null;
+ private DataInputStream inputStream = null;
+ private Thread controlThread = null;
+ private boolean infoAvailable = false;
+ private int updateDelay = 750;
+
+ // Image decoding state variables
+ private boolean headerFound = false;
+ private int compressionMethod = -1;
+ private int depth = -1;
+ private int colorType = -1;
+ private int filterMethod = -1;
+ private int interlaceMethod = -1;
+ private int pass = 0;
+ private byte palette[] = null;
+ private int mask = 0x0;
+ private int smask = 0x0;
+ private boolean transparency = false;
+
+ private int chunkLength = 0;
+ private int chunkType = 0;
+ private boolean needChunkInfo = true;
+
+ private static final int CHUNK_bKGD = 0x624B4744; // "bKGD"
+ private static final int CHUNK_cHRM = 0x6348524D; // "cHRM"
+ private static final int CHUNK_gAMA = 0x67414D41; // "gAMA"
+ private static final int CHUNK_hIST = 0x68495354; // "hIST"
+ private static final int CHUNK_IDAT = 0x49444154; // "IDAT"
+ private static final int CHUNK_IEND = 0x49454E44; // "IEND"
+ private static final int CHUNK_IHDR = 0x49484452; // "IHDR"
+ private static final int CHUNK_PLTE = 0x504C5445; // "PLTE"
+ private static final int CHUNK_pHYs = 0x70485973; // "pHYs"
+ private static final int CHUNK_sBIT = 0x73424954; // "sBIT"
+ private static final int CHUNK_tEXt = 0x74455874; // "tEXt"
+ private static final int CHUNK_tIME = 0x74494D45; // "tIME"
+ private static final int CHUNK_tRNS = 0x74524E53; // "tIME"
+ private static final int CHUNK_zTXt = 0x7A545874; // "zTXt"
+
+ private static final int startingRow[] = { 0, 0, 0, 4, 0, 2, 0, 1 };
+ private static final int startingCol[] = { 0, 0, 4, 0, 2, 0, 1, 0 };
+ private static final int rowInc[] = { 1, 8, 8, 8, 4, 4, 2, 2 };
+ private static final int colInc[] = { 1, 8, 8, 4, 4, 2, 2, 1 };
+ private static final int blockHeight[] = { 1, 8, 8, 4, 4, 2, 2, 1 };
+ private static final int blockWidth[] = { 1, 8, 4, 4, 2, 2, 1, 1 };
+
+ // Helper Classes ////////////////////////////////////////////////////////////////////
+
+ private static class MeteredInputStream extends FilterInputStream {
+ int bytesLeft;
+ int marked;
+
+ public MeteredInputStream(InputStream in, int size) {
+ super(in);
+ bytesLeft = size;
+ }
+
+ public final int read() throws IOException {
+ if (bytesLeft > 0) {
+ int val = in.read();
+ if (val != -1) bytesLeft--;
+ return val;
+ }
+ return -1;
+ }
+
+ public final int read(byte b[]) throws IOException {
+ return read(b, 0, b.length);
+ }
+
+ public final int read(byte b[], int off, int len) throws IOException {
+ if (bytesLeft > 0) {
+ len = (len > bytesLeft ? bytesLeft : len);
+ int read = in.read(b, off, len);
+ if (read > 0) bytesLeft -= read;
+ return read;
+ }
+ return -1;
+ }
+
+ public final long skip(long n) throws IOException {
+ n = (n > bytesLeft ? bytesLeft : n);
+ long skipped = in.skip(n);
+ if (skipped > 0) bytesLeft -= skipped;
+ return skipped;
+ }
+
+ public final int available() throws IOException {
+ int n = in.available();
+ return (n > bytesLeft ? bytesLeft : n);
+ }
+
+ public final void close() throws IOException { /* Eat this */ }
+
+ public final void mark(int readlimit) {
+ marked = bytesLeft;
+ in.mark(readlimit);
+ }
+
+ public final void reset() throws IOException {
+ in.reset();
+ bytesLeft = marked;
+ }
+
+ public final boolean markSupported() { return in.markSupported(); }
+ }
+
+ /** Support class, used to eat the IDAT headers dividing up the deflated stream */
+ private static class IDATEnumeration implements Enumeration {
+ InputStream underlyingStream;
+ PNG owner;
+ boolean firstStream = true;
+
+ public IDATEnumeration(PNG owner) {
+ this.owner = owner;
+ this.underlyingStream = owner.underlyingStream;
+ }
+
+ public Object nextElement() {
+ firstStream = false;
+ return new MeteredInputStream(underlyingStream, owner.chunkLength);
+ }
+
+ public boolean hasMoreElements() {
+ DataInputStream dis = new DataInputStream(underlyingStream);
+ if (!firstStream) {
+ try {
+ int crc = dis.readInt();
+ owner.needChunkInfo = false;
+ owner.chunkLength = dis.readInt();
+ owner.chunkType = dis.readInt();
+ } catch (IOException ioe) {
+ return false;
+ }
+ }
+ if (owner.chunkType == PNG.CHUNK_IDAT) return true;
+ return false;
+ }
+ }
+
+}
projects / org.ibex.core.git / blobdiff