/*
* Copyright (c) 2012, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name "TwelveMonkeys" nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Parts of this code is based on ilbmtoppm.c
*
* Copyright (C) 1989 by Jef Poskanzer.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted, provided
* that the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. This software is provided "as is" without express or
* implied warranty.
*
* Multipalette-support by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
*/
package com.twelvemonkeys.imageio.plugins.iff;
import javax.imageio.IIOException;
import java.io.DataInput;
import java.io.IOException;
/**
* PCHGChunk
*
* @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>
* @author last modified by $Author: haraldk$
* @version $Id: PCHGChunk.java,v 1.0 27.03.12 13:02 haraldk Exp$
*/
final class PCHGChunk extends AbstractMultiPaletteChunk {
// NOTE: Values from ilbm2ppm.
final static int PCHG_COMP_NONE = 0;
final static int PCHG_COMP_HUFFMAN = 1;
/** Use SmallLineChanges */
final static int PCHGF_12BIT = 1; // NOTE: The beta spec refers to this as PHCGF_4BIT
/** Use BigLineChanges */
final static int PCHGF_32BIT = 2;
/** meaningful only if PCHG_32BIT is on: use the Alpha channel info */
final static int PCHGF_USE_ALPHA = 4;
private int startLine;
private int changedLines;
private int lineCount;
private int totalChanges;
private int minReg;
public PCHGChunk(int pChunkLength) {
super(IFF.CHUNK_PCHG, pChunkLength);
}
@Override
void readChunk(final DataInput pInput) throws IOException {
int compression = pInput.readUnsignedShort();
int flags = pInput.readUnsignedShort();
startLine = pInput.readShort();
lineCount = pInput.readUnsignedShort();
changedLines = pInput.readUnsignedShort();
minReg = pInput.readUnsignedShort();
int maxReg = pInput.readUnsignedShort();
/*int maxChangesPerLine = */pInput.readUnsignedShort(); // We don't really care, as we're not limited by the Amiga display hardware
totalChanges = pInput.readInt();
byte[] data;
switch (compression) {
case PCHG_COMP_NONE:
data = new byte[chunkLength - 20];
pInput.readFully(data);
break;
case PCHG_COMP_HUFFMAN:
// NOTE: Huffman decompression is completely untested, due to lack of source data (read: Probably broken).
int compInfoSize = pInput.readInt();
int originalDataSize = pInput.readInt();
short[] compTree = new short[compInfoSize / 2];
for (int i = 0; i < compTree.length; i++) {
compTree[i] = pInput.readShort();
}
byte[] compData = new byte[chunkLength - 20 - 8 - compInfoSize];
pInput.readFully(compData);
data = new byte[originalDataSize];
// decompress the change structure data
decompressHuffman(compData, data, compTree, data.length);
default:
throw new IIOException("Unknown PCHG compression: " + compression);
}
changes = new MutableIndexColorModel.PaletteChange[startLine + lineCount][];
if (startLine < 0) {
int numChanges = maxReg - minReg + 1;
initialChanges = new MutableIndexColorModel.PaletteChange[numChanges];
}
// TODO: Postpone conversion to when the data is actually needed
parseChanges(data, flags);
}
static void decompressHuffman(byte[] src, byte[] dest, short[] tree, int origSize) {
int i = 0;
int bits = 0;
int thisbyte = 0;
int treeIdx = tree.length - 1;
int srcIdx = 0;
int destIdx = 0;
while (i < origSize) {
if (bits == 0) {
thisbyte = src[srcIdx++];
bits = 8;
}
if ((thisbyte & (1 << 7)) != 0) {
if (tree[treeIdx] >= 0) {
dest[destIdx++] = (byte) tree[treeIdx];
i++;
treeIdx = tree.length - 1;
}
else {
treeIdx += tree[treeIdx] / 2;
}
}
else {
treeIdx--;
if (tree[treeIdx] > 0 && (tree[treeIdx] & 0x100) != 0) {
dest[destIdx++] = (byte) tree[treeIdx];
i++;
treeIdx = tree.length - 1;
}
}
thisbyte <<= 1;
bits--;
}
}
private void parseChanges(final byte[] data, int flags) throws IIOException {
boolean small;
if ((flags & PCHGF_12BIT) != 0) {
small = true;
}
else if ((flags & PCHGF_32BIT) != 0) {
if ((flags & PCHGF_USE_ALPHA) != 0) {
// TODO: Warning, or actually implement
new IIOException("Alpha currently not supported.").printStackTrace();
}
small = false;
}
else {
throw new IIOException("Missing PCHG 12/32 bit flag.");
}
int thismask = 0;
int changeCount;
int totalchanges = 0;
int changedlines = changedLines;
int maskBytesLeft = 4 * ((lineCount + 31) / 32);
int maskIdx = 0;
int dataIdx = maskBytesLeft;
int dataBytesLeft = data.length - maskBytesLeft;
int bits = 0;
for (int row = startLine; changedlines != 0 && row < 0; row++) {
if (bits == 0) {
if (maskBytesLeft == 0) {
throw new IIOException("Insufficient data in line mask");
}
thismask = data[maskIdx++];
--maskBytesLeft;
bits = 8;
}
if ((thismask & (1 << 7)) != 0) {
if (dataBytesLeft < 2) {
throw new IIOException("Insufficient data in SmallLineChanges structures: " + dataBytesLeft);
}
int changeCount16 = 0;
if (small) {
changeCount16 = data[dataIdx++] & 0xff;
changeCount = changeCount16 + (data[dataIdx++] & 0xff);
}
else {
changeCount = toShort(data, dataIdx);
dataIdx += 2;
}
dataBytesLeft -= 2;
for (int i = 0; i < changeCount; i++) {
if (totalchanges >= this.totalChanges) {
throw new IIOException("Insufficient data in SmallLineChanges structures (changeCount): " + totalchanges);
}
if (dataBytesLeft < 2) {
throw new IIOException("Insufficient data in SmallLineChanges structures: " + dataBytesLeft);
}
// TODO: Make PaletteChange immutable with constructor params, assign outside test?
if (small) {
int smallChange = toShort(data, dataIdx);
dataIdx += 2;
dataBytesLeft -= 2;
int reg = ((smallChange & 0xf000) >> 12) + (i >= changeCount16 ? 16 : 0);
initialChanges[reg - minReg] = new MutableIndexColorModel.PaletteChange();
initialChanges[reg - minReg].index = reg;
initialChanges[reg - minReg].r = (byte) (((smallChange & 0x0f00) >> 8) * FACTOR_4BIT);
initialChanges[reg - minReg].g = (byte) (((smallChange & 0x00f0) >> 4) * FACTOR_4BIT);
initialChanges[reg - minReg].b = (byte) (((smallChange & 0x000f) ) * FACTOR_4BIT);
}
else {
int reg = toShort(data, dataIdx);
dataIdx += 2;
initialChanges[reg - minReg] = new MutableIndexColorModel.PaletteChange();
initialChanges[reg - minReg].index = reg;
dataIdx++; /* skip alpha */
initialChanges[reg - minReg].r = data[dataIdx++];
initialChanges[reg - minReg].b = data[dataIdx++]; /* yes, RBG */
initialChanges[reg - minReg].g = data[dataIdx++];
dataBytesLeft -= 6;
}
++totalchanges;
}
--changedlines;
}
thismask <<= 1;
bits--;
}
for (int row = startLine; changedlines != 0 && row < changes.length; row++) {
if (bits == 0) {
if (maskBytesLeft == 0) {
throw new IIOException("Insufficient data in line mask");
}
thismask = data[maskIdx++];
--maskBytesLeft;
bits = 8;
}
if ((thismask & (1 << 7)) != 0) {
if (dataBytesLeft < 2) {
throw new IIOException("Insufficient data in SmallLineChanges structures: " + dataBytesLeft);
}
int changeCount16 = 0;
if (small) {
changeCount16 = data[dataIdx++] & 0xff;
changeCount = changeCount16 + (data[dataIdx++] & 0xff);
}
else {
changeCount = toShort(data, dataIdx);
dataIdx += 2;
}
dataBytesLeft -= 2;
changes[row] = new MutableIndexColorModel.PaletteChange[changeCount];
for (int i = 0; i < changeCount; i++) {
if (totalchanges >= this.totalChanges) {
throw new IIOException("Insufficient data in SmallLineChanges structures (changeCount): " + totalchanges);
}
if (dataBytesLeft < 2) {
throw new IIOException("Insufficient data in SmallLineChanges structures: " + dataBytesLeft);
}
if (small) {
int smallChange = toShort(data, dataIdx);
dataIdx += 2;
dataBytesLeft -= 2;
int reg = ((smallChange & 0xf000) >> 12) + (i >= changeCount16 ? 16 : 0);
MutableIndexColorModel.PaletteChange paletteChange = new MutableIndexColorModel.PaletteChange();
paletteChange.index = reg;
paletteChange.r = (byte) (((smallChange & 0x0f00) >> 8) * FACTOR_4BIT);
paletteChange.g = (byte) (((smallChange & 0x00f0) >> 4) * FACTOR_4BIT);
paletteChange.b = (byte) (((smallChange & 0x000f) ) * FACTOR_4BIT);
changes[row][i] = paletteChange;
}
else {
int reg = toShort(data, dataIdx);
dataIdx += 2;
MutableIndexColorModel.PaletteChange paletteChange = new MutableIndexColorModel.PaletteChange();
paletteChange.index = reg;
dataIdx++; /* skip alpha */
paletteChange.r = data[dataIdx++];
paletteChange.b = data[dataIdx++]; /* yes, RBG */
paletteChange.g = data[dataIdx++];
changes[row][i] = paletteChange;
dataBytesLeft -= 6;
}
++totalchanges;
}
--changedlines;
}
thismask <<= 1;
bits--;
}
if (totalchanges != this.totalChanges) {
// TODO: Issue IIO warning
new IIOException(String.format("Got %d change structures, chunk header reports %d", totalchanges, this.totalChanges)).printStackTrace();
}
}
// TODO: Util method
private static short toShort(byte[] bytes, int idx) {
return (short) ((bytes[idx] & 0xff) << 8 | (bytes[idx + 1] & 0xff));
}
}