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|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* 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 for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
// Based on http://wiki.multimedia.cx/index.php?title=Smacker
// and the FFmpeg Smacker decoder (libavcodec/smacker.c), revision 16143
// http://svn.ffmpeg.org/ffmpeg/trunk/libavcodec/smacker.c?revision=16143&view=markup
#include "graphics/video/smk_player.h"
#include "common/archive.h"
#include "common/system.h"
#include "common/util.h"
#include "common/array.h"
#include "common/endian.h"
#include "sound/mixer.h"
#include "sound/audiostream.h"
namespace Graphics {
enum SmkBlockTypes {
SMK_BLOCK_MONO = 0,
SMK_BLOCK_FULL = 1,
SMK_BLOCK_SKIP = 2,
SMK_BLOCK_FILL = 3
};
/*
* class BitStream
* Keeps a two-byte lookahead, so overallocate buf by 2 bytes if
* you want to avoid OOB reads.
*/
class BitStream {
public:
BitStream(byte *buf, uint32 length)
: _buf(buf), _end(buf+length), _curBit(8) {
_curBytes = *_buf++;
_curBytes |= *_buf++ << 8;
}
bool getBit();
byte getBits8();
byte peek8() const;
void skip(int n);
private:
byte *_buf;
byte *_end;
uint16 _curBytes;
byte _curBit;
};
bool BitStream::getBit() {
bool v = _curBytes & 1;
_curBytes >>= 1;
if (--_curBit == 0) {
_curBytes |= *_buf++ << 8;
_curBit = 8;
}
return v;
}
byte BitStream::getBits8() {
byte v = _curBytes & 0xff;
_curBytes >>= 8;
_curBytes |= *_buf++ << _curBit;
return v;
}
byte BitStream::peek8() const {
return _curBytes & 0xff;
}
void BitStream::skip(int n) {
assert(n <= 8);
_curBytes >>= n;
if (_curBit > n) {
_curBit -= n;
} else {
_curBit = _curBit + 8 - n;
_curBytes |= *_buf++ << _curBit;
}
}
/*
* class SmallHuffmanTree
* A Huffman-tree to hold 8-bit values.
* Unoptimized since it's only used during smk initialization.
*/
class SmallHuffmanTree {
public:
SmallHuffmanTree(BitStream &bs) : _bs(bs) {
uint32 bit = _bs.getBit();
assert(bit);
decodeTree(0);
bit = _bs.getBit();
assert(!bit);
}
uint16 getCode(BitStream &bs);
private:
enum {
SMK_NODE = 0x8000
};
int decodeTree(int length);
Common::Array<uint16> _tree;
BitStream &_bs;
};
int SmallHuffmanTree::decodeTree(int length) {
if (!_bs.getBit()) { // Leaf
uint16 v = _bs.getBits8();
_tree.push_back(v);
return 1;
}
_tree.push_back(0); // placeholder for r1
int t = _tree.size() - 1;
int r1 = decodeTree(length + 1);
_tree[t] = (SMK_NODE | r1);
int r2 = decodeTree(length + 1);
return r1+r2+1;
}
uint16 SmallHuffmanTree::getCode(BitStream &bs) {
uint16 *p = &_tree[0];
while (*p & SMK_NODE) {
if (bs.getBit())
p += *p & ~SMK_NODE;
p++;
}
return *p;
}
/*
* class BigHuffmanTree
* A Huffman-tree to hold 16-bit values.
* Contains the beginnings of an optimization.
*/
class BigHuffmanTree {
public:
BigHuffmanTree(BitStream &bs);
void reset();
uint32 getCode(BitStream &bs);
private:
enum {
SMK_NODE = 0x80000000
};
int decodeTree(uint32 prefix, int length);
Common::Array<uint32> _tree;
uint32 _last[3];
int _prefixtree[256];
int _prefixlength[256];
/* Used during construction */
BitStream &_bs;
uint32 _markers[3];
SmallHuffmanTree *_loBytes;
SmallHuffmanTree *_hiBytes;
};
BigHuffmanTree::BigHuffmanTree(BitStream &bs)
: _bs(bs) {
uint32 bit = _bs.getBit();
if (!bit) {
_tree.push_back(0);
_last[0] = _last[1] = _last[2] = 0;
return;
}
int i;
for (i = 0; i < 256; ++i)
_prefixtree[i] = 0;
_loBytes = new SmallHuffmanTree(_bs);
_hiBytes = new SmallHuffmanTree(_bs);
_markers[0] = _bs.getBits8() | (_bs.getBits8() << 8);
_markers[1] = _bs.getBits8() | (_bs.getBits8() << 8);
_markers[2] = _bs.getBits8() | (_bs.getBits8() << 8);
_last[0] = _last[1] = _last[2] = 0xffffffff;
decodeTree(0, 0);
bit = _bs.getBit();
assert(!bit);
for (i = 0; i < 3; ++i) {
if (_last[i] == 0xffffffff) {
_tree.push_back(0);
_last[i] = _tree.size() - 1;
}
}
delete _loBytes;
delete _hiBytes;
}
void BigHuffmanTree::reset() {
_tree[_last[0]] = _tree[_last[1]] = _tree[_last[2]] = 0;
}
int BigHuffmanTree::decodeTree(uint32 prefix, int length) {
uint32 bit = _bs.getBit();
if (!bit) { // Leaf
uint32 lo = _loBytes->getCode(_bs);
uint32 hi = _hiBytes->getCode(_bs);
uint32 v = (hi << 8) | lo;
_tree.push_back(v);
int t = _tree.size() - 1;
if (length <= 8) {
uint32 i;
for (i = 0; i < 256; i += (1 << length)) {
_prefixtree[prefix | i] = t;
_prefixlength[prefix | i] = length;
}
}
int i;
for (i = 0; i < 3; ++i) {
if (_markers[i] == v) {
_last[i] = t;
_tree[t] = 0;
}
}
return 1;
}
_tree.push_back(0); // placeholder for r1
int t = _tree.size() - 1;
if (length == 8) {
_prefixtree[prefix] = t;
_prefixlength[prefix] = 8;
}
int r1 = decodeTree(prefix, length + 1);
_tree[t] = SMK_NODE | r1;
int r2 = decodeTree(prefix | (1 << length), length + 1);
return r1+r2+1;
}
uint32 BigHuffmanTree::getCode(BitStream &bs) {
uint32 *p = &_tree[0];
byte peek = bs.peek8();
p = &_tree[_prefixtree[peek]];
bs.skip(_prefixlength[peek]);
while (*p & SMK_NODE) {
if (bs.getBit())
p += (*p) & ~SMK_NODE;
p++;
}
uint32 v = *p;
if (v != _tree[_last[0]]) {
_tree[_last[2]] = _tree[_last[1]];
_tree[_last[1]] = _tree[_last[0]];
_tree[_last[0]] = v;
}
return v;
}
SMKPlayer::SMKPlayer(Audio::Mixer *mixer)
: _audioStarted(false), _audioStream(0), _mixer(mixer) {
}
SMKPlayer::~SMKPlayer() {
}
int SMKPlayer::getHeight() {
if (!_fileStream)
return 0;
return (_header.flags ? 2 : 1) * _videoInfo.height;
}
int32 SMKPlayer::getAudioLag() {
if (!_fileStream)
return 0;
int32 frameDelay = getFrameDelay();
int32 videoTime = _videoInfo.currentFrame * frameDelay;
int32 audioTime;
if (!_audioStream) {
/* No audio.
Calculate the lag by how much time has gone by since the first frame
and how much time *should* have passed.
*/
audioTime = (g_system->getMillis() - _videoInfo.startTime) * 100;
} else
audioTime = (((int32) _mixer->getSoundElapsedTime(_audioHandle)) * 100);
return videoTime - audioTime;
}
bool SMKPlayer::loadFile(const char *fileName) {
int32 frameRate;
closeFile();
_fileStream = SearchMan.openFile(fileName);
if (!_fileStream)
return false;
// Seek to the first frame
_videoInfo.currentFrame = 0;
_header.signature = _fileStream->readUint32BE();
// No BINK support available
if (_header.signature == MKID_BE('BIKi')) {
delete _fileStream;
_fileStream = 0;
return false;
}
assert(_header.signature == MKID_BE('SMK2') || _header.signature == MKID_BE('SMK4'));
_videoInfo.width = _fileStream->readUint32LE();
_videoInfo.height = _fileStream->readUint32LE();
_videoInfo.frameCount = _fileStream->readUint32LE();
frameRate = _fileStream->readSint32LE();
if (frameRate > 0) {
_videoInfo.frameRate = 1000 / frameRate;
_videoInfo.frameDelay = frameRate * 100;
} else if (frameRate < 0) {
_videoInfo.frameRate = 100000 / (-frameRate);
_videoInfo.frameDelay = -frameRate;
} else {
_videoInfo.frameRate = 10;
_videoInfo.frameDelay = 10000;
}
// Flags are determined by which bit is set, which can be one of the following:
// 0 - set to 1 if file contains a ring frame.
// 1 - set to 1 if file is Y-interlaced
// 2 - set to 1 if file is Y-doubled
// If bits 1 or 2 are set, the frame should be scaled to twice its height
// before it is displayed.
_header.flags = _fileStream->readUint32LE();
// TODO: should we do any extra processing for Smacker files with ring frames?
// TODO: should we do any extra processing for Y-doubled videos? Are they the
// same as Y-interlaced videos?
uint32 i;
for (i = 0; i < 7; ++i)
_header.audioSize[i] = _fileStream->readUint32LE();
_header.treesSize = _fileStream->readUint32LE();
_header.mMapSize = _fileStream->readUint32LE();
_header.mClrSize = _fileStream->readUint32LE();
_header.fullSize = _fileStream->readUint32LE();
_header.typeSize = _fileStream->readUint32LE();
uint32 audioInfo;
for (i = 0; i < 7; ++i) {
// AudioRate - Frequency and format information for each sound track, up to 7 audio tracks.
// The 32 constituent bits have the following meaning:
// * bit 31 - data is compressed
// * bit 30 - indicates that audio data is present for this track
// * bit 29 - 1 = 16-bit audio; 0 = 8-bit audio
// * bit 28 - 1 = stereo audio; 0 = mono audio
// * bits 27-26 - if both set to zero - use v2 sound decompression
// * bits 25-24 - unused
// * bits 23-0 - audio sample rate
audioInfo = _fileStream->readUint32LE();
_header.audioInfo[i].isCompressed = audioInfo & 0x80000000;
_header.audioInfo[i].hasAudio = audioInfo & 0x40000000;
_header.audioInfo[i].is16Bits = audioInfo & 0x20000000;
_header.audioInfo[i].isStereo = audioInfo & 0x10000000;
_header.audioInfo[i].hasV2Compression = !(audioInfo & 0x8000000) &&
!(audioInfo & 0x4000000);
_header.audioInfo[i].sampleRate = audioInfo & 0xFFFFFF;
if (_header.audioInfo[i].hasAudio && i == 0) {
byte flags = 0;
if (_header.audioInfo[i].is16Bits)
flags = flags | Audio::Mixer::FLAG_16BITS;
if (_header.audioInfo[i].isStereo)
flags = flags | Audio::Mixer::FLAG_STEREO;
_audioStream = Audio::makeAppendableAudioStream(_header.audioInfo[i].sampleRate, flags);
}
}
_header.dummy = _fileStream->readUint32LE();
_frameSizes = (uint32 *)malloc(_videoInfo.frameCount * sizeof(uint32));
for (i = 0; i < _videoInfo.frameCount; ++i)
_frameSizes[i] = _fileStream->readUint32LE();
_frameTypes = (byte *)malloc(_videoInfo.frameCount);
for (i = 0; i < _videoInfo.frameCount; ++i)
_frameTypes[i] = _fileStream->readByte();
Common::Array<byte> huffmanTrees;
huffmanTrees.resize(_header.treesSize + 2);
_fileStream->read(&huffmanTrees[0], _header.treesSize);
huffmanTrees[_header.treesSize] = 0;
huffmanTrees[_header.treesSize + 1] = 0;
BitStream bs(&huffmanTrees[0], _header.treesSize);
_MMapTree = new BigHuffmanTree(bs);
_MClrTree = new BigHuffmanTree(bs);
_FullTree = new BigHuffmanTree(bs);
_TypeTree = new BigHuffmanTree(bs);
_videoFrameBuffer = (byte *)malloc(2 * _videoInfo.width * _videoInfo.height);
memset(_videoFrameBuffer, 0, 2 * _videoInfo.width * _videoInfo.height);
_palette = (byte *)malloc(3 * 256);
memset(_palette, 0, 3 * 256);
return true;
}
void SMKPlayer::closeFile() {
if (!_fileStream)
return;
if (_audioStarted && _audioStream) {
_mixer->stopHandle(_audioHandle);
_audioStream = 0;
_audioStarted = false;
}
delete _fileStream;
_fileStream = 0;
delete _MMapTree;
delete _MClrTree;
delete _FullTree;
delete _TypeTree;
free(_frameSizes);
free(_frameTypes);
free(_videoFrameBuffer);
free(_palette);
}
bool SMKPlayer::decodeNextFrame() {
uint i;
uint32 chunkSize = 0;
uint32 dataSizeUnpacked = 0;
uint32 startPos = _fileStream->pos();
if (_videoInfo.currentFrame == 0)
_videoInfo.startTime = g_system->getMillis();
// Check if we got a frame with palette data, and
// call back the virtual setPalette function to set
// the current palette
if (_frameTypes[_videoInfo.currentFrame] & 1) {
unpackPalette();
setPalette(_palette);
}
// Load audio tracks
for (i = 0; i < 7; ++i) {
if (!(_frameTypes[_videoInfo.currentFrame] & (2 << i)))
continue;
chunkSize = _fileStream->readUint32LE();
chunkSize -= 4; // subtract the first 4 bytes (chunk size)
if (_header.audioInfo[i].isCompressed) {
dataSizeUnpacked = _fileStream->readUint32LE();
chunkSize -= 4; // subtract the next 4 bytes (unpacked data size)
} else {
dataSizeUnpacked = 0;
}
if (_header.audioInfo[i].hasAudio && chunkSize > 0 && i == 0) {
// If it's track 0, play the audio data
byte *soundBuffer = new byte[chunkSize + 2];
_fileStream->read(soundBuffer, chunkSize);
soundBuffer[chunkSize] = 0;
soundBuffer[chunkSize + 1] = 0;
if (_header.audioInfo[i].isCompressed) {
// Compressed audio (Huffman DPCM encoded)
queueCompressedBuffer(soundBuffer, chunkSize, dataSizeUnpacked, i);
delete[] soundBuffer;
} else {
// Uncompressed audio (PCM)
_audioStream->queueBuffer(soundBuffer, chunkSize);
// The sound buffer will be deleted by AppendableAudioStream
}
if (!_audioStarted) {
_mixer->playInputStream(Audio::Mixer::kPlainSoundType, &_audioHandle, _audioStream, -1, 255);
_audioStarted = true;
}
} else {
// Ignore the rest of the audio tracks, if they exist
// TODO: Are there any Smacker videos with more than one audio stream?
// If yes, we should play the rest of the audio streams as well
if (chunkSize > 0)
_fileStream->skip(chunkSize);
}
}
uint32 frameSize = _frameSizes[_videoInfo.currentFrame] & ~3;
if (_fileStream->pos() - startPos > frameSize)
exit(1);
uint32 frameDataSize = frameSize - (_fileStream->pos() - startPos);
_frameData = (byte *)malloc(frameDataSize + 2);
_fileStream->read(_frameData, frameDataSize);
_frameData[frameDataSize] = 0;
_frameData[frameDataSize + 1] = 0;
BitStream bs(_frameData, frameDataSize);
_MMapTree->reset();
_MClrTree->reset();
_FullTree->reset();
_TypeTree->reset();
uint bw = _videoInfo.width / 4;
uint bh = _videoInfo.height / 4;
uint stride = _videoInfo.width;
uint block = 0, blocks = bw*bh;
uint doubleY = _header.flags ? 2 : 1;
byte *out;
uint type, run, j, mode;
uint32 p1, p2, clr, map;
byte hi, lo;
while (block < blocks) {
type = _TypeTree->getCode(bs);
run = getBlockRun((type >> 2) & 0x3f);
switch (type & 3) {
case SMK_BLOCK_MONO:
while (run-- && block < blocks) {
clr = _MClrTree->getCode(bs);
map = _MMapTree->getCode(bs);
out = _videoFrameBuffer + (block / bw) * (stride * 4 * doubleY) + (block % bw) * 4;
hi = clr >> 8;
lo = clr & 0xff;
for (i = 0; i < 4; i++) {
for (j = 0; j < doubleY; j++) {
out[0] = (map & 1) ? hi : lo;
out[1] = (map & 2) ? hi : lo;
out[2] = (map & 4) ? hi : lo;
out[3] = (map & 8) ? hi : lo;
out += stride;
}
map >>= 4;
}
++block;
}
break;
case SMK_BLOCK_FULL:
// Smacker v2 has one mode, Smacker v4 has three
if (_header.signature == MKID_BE('SMK2')) {
mode = 0;
} else {
// 00 - mode 0
// 10 - mode 1
// 01 - mode 2
mode = 0;
if (bs.getBit()) {
mode = 1;
} else if (bs.getBit()) {
mode = 2;
}
}
while (run-- && block < blocks) {
out = _videoFrameBuffer + (block / bw) * (stride * 4 * doubleY) + (block % bw) * 4;
switch (mode) {
case 0:
for (i = 0; i < 4; ++i) {
p1 = _FullTree->getCode(bs);
p2 = _FullTree->getCode(bs);
for (j = 0; j < doubleY; ++j) {
out[2] = p1 & 0xff;
out[3] = p1 >> 8;
out[0] = p2 & 0xff;
out[1] = p2 >> 8;
out += stride;
}
}
break;
case 1:
p1 = _FullTree->getCode(bs);
out[0] = out[1] = p1 & 0xFF;
out[2] = out[3] = p1 >> 8;
out += stride;
out[0] = out[1] = p1 & 0xFF;
out[2] = out[3] = p1 >> 8;
out += stride;
p2 = _FullTree->getCode(bs);
out[0] = out[1] = p2 & 0xFF;
out[2] = out[3] = p2 >> 8;
out += stride;
out[0] = out[1] = p2 & 0xFF;
out[2] = out[3] = p2 >> 8;
out += stride;
break;
case 2:
for(i = 0; i < 2; i++) {
// We first get p2 and then p1
// Check ffmpeg thread "[PATCH] Smacker video decoder bug fix"
// http://article.gmane.org/gmane.comp.video.ffmpeg.devel/78768
p2 = _FullTree->getCode(bs);
p1 = _FullTree->getCode(bs);
for (j = 0; j < doubleY; ++j) {
out[0] = p1 & 0xff;
out[1] = p1 >> 8;
out[2] = p2 & 0xff;
out[3] = p2 >> 8;
out += stride;
}
for (j = 0; j < doubleY; ++j) {
out[0] = p1 & 0xff;
out[1] = p1 >> 8;
out[2] = p2 & 0xff;
out[3] = p2 >> 8;
out += stride;
}
}
break;
}
++block;
}
break;
case SMK_BLOCK_SKIP:
while (run-- && block < blocks)
block++;
break;
case SMK_BLOCK_FILL:
uint32 col;
mode = type >> 8;
while (run-- && block < blocks) {
out = _videoFrameBuffer + (block / bw) * (stride * 4 * doubleY) + (block % bw) * 4;
col = mode * 0x01010101;
for (i = 0; i < 4 * doubleY; ++i) {
out[0] = out[1] = out[2] = out[3] = col;
out += stride;
}
++block;
}
break;
}
}
_fileStream->seek(startPos + frameSize);
free(_frameData);
return ++_videoInfo.currentFrame < _videoInfo.frameCount;
}
void SMKPlayer::queueCompressedBuffer(byte *buffer, uint32 bufferSize,
uint32 unpackedSize, int streamNum) {
BitStream audioBS(buffer, bufferSize);
bool dataPresent = audioBS.getBit();
if (!dataPresent)
return;
bool isStereo = audioBS.getBit();
assert(isStereo == _header.audioInfo[streamNum].isStereo);
bool is16Bits = audioBS.getBit();
assert(is16Bits == _header.audioInfo[streamNum].is16Bits);
int numBytes = 1 * (isStereo ? 2 : 1) * (is16Bits ? 2 : 1);
byte *unpackedBuffer = new byte[unpackedSize];
byte *curPointer = unpackedBuffer;
uint32 curPos = 0;
SmallHuffmanTree *audioTrees[4];
for (int k = 0; k < numBytes; k++)
audioTrees[k] = new SmallHuffmanTree(audioBS);
// Base values, stored as big endian
int32 bases[2];
if (isStereo)
bases[1] = (!is16Bits) ? audioBS.getBits8() :
((int16) (((audioBS.getBits8() << 8) | audioBS.getBits8())));
bases[0] = (!is16Bits) ? audioBS.getBits8() :
((int16) (((audioBS.getBits8() << 8) | audioBS.getBits8())));
// The bases are the first samples, too
for (int i = 0; i < (isStereo ? 2 : 1); i++, curPointer += (is16Bits ? 2 : 1), curPos += (is16Bits ? 2 : 1)) {
if (is16Bits)
WRITE_BE_UINT16(curPointer, bases[i]);
else
*curPointer = (bases[i] & 0xFF) ^ 0x80;
}
// Next follow the deltas, which are added to the corresponding base values and
// are stored as little endian
// We store the unpacked bytes in big endian format
while (curPos < unpackedSize) {
// If the sample is stereo, the data is stored for the left and right channel, respectively
// (the exact opposite to the base values)
if (!is16Bits) {
for (int k = 0; k < (isStereo ? 2 : 1); k++) {
bases[k] += (int8) ((int16) audioTrees[k]->getCode(audioBS));
*curPointer++ = CLIP<int>(bases[k], 0, 255) ^ 0x80;
curPos++;
}
} else {
for (int k = 0; k < (isStereo ? 2 : 1); k++) {
bases[k] += (int16) (audioTrees[k * 2]->getCode(audioBS) |
(audioTrees[k * 2 + 1]->getCode(audioBS) << 8));
WRITE_BE_UINT16(curPointer, CLIP<int32>(bases[k], -32768, 32767));
curPointer += 2;
curPos += 2;
}
}
}
for (int k = 0; k < numBytes; k++)
delete audioTrees[k];
_audioStream->queueBuffer(unpackedBuffer, unpackedSize);
// unpackedBuffer will be deleted by AppendableAudioStream
}
void SMKPlayer::unpackPalette() {
uint startPos = _fileStream->pos();
uint32 len = 4 * _fileStream->readByte();
byte *chunk = (byte *)malloc(len);
_fileStream->read(&chunk[0], len);
byte *p = &chunk[0];
byte oldPalette[3*256];
memcpy(oldPalette, _palette, 3 * 256);
byte *pal = _palette;
int sz = 0;
byte b0;
while (sz < 256) {
b0 = *p++;
if (b0 & 0x80) { // if top bit is 1 (0x80 = 10000000)
sz += (b0 & 0x7f) + 1; // get lower 7 bits + 1 (0x7f = 01111111)
pal += 3 * ((b0 & 0x7f) + 1);
} else if (b0 & 0x40) { // if top 2 bits are 01 (0x40 = 01000000)
byte c = (b0 & 0x3f) + 1; // get lower 6 bits + 1 (0x3f = 00111111)
uint s = 3 * *p++;
sz += c;
while (c--) {
*pal++ = oldPalette[s + 0];
*pal++ = oldPalette[s + 1];
*pal++ = oldPalette[s + 2];
s += 3;
}
} else { // top 2 bits are 00
sz++;
// get the lower 6 bits for each component (0x3f = 00111111)
byte b = b0 & 0x3f;
byte g = (*p++) & 0x3f;
byte r = (*p++) & 0x3f;
assert(g < 0xc0 && b < 0xc0);
// upscale to full 8-bit color values by multiplying by 4
*pal++ = b * 4;
*pal++ = g * 4;
*pal++ = r * 4;
}
}
_fileStream->seek(startPos + len);
free(chunk);
}
} // End of namespace Graphics
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