scummvm/video/smk_decoder.cpp
2012-08-20 17:06:58 -04:00

863 lines
23 KiB
C++

/* 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.
*
*/
// Based on http://wiki.multimedia.cx/index.php?title=Smacker
// and the FFmpeg Smacker decoder (libavcodec/smacker.c), revision 16143
// http://git.ffmpeg.org/?p=ffmpeg;a=blob;f=libavcodec/smacker.c;hb=b8437a00a2f14d4a437346455d624241d726128e
#include "video/smk_decoder.h"
#include "common/endian.h"
#include "common/util.h"
#include "common/stream.h"
#include "common/memstream.h"
#include "common/bitstream.h"
#include "common/system.h"
#include "common/textconsole.h"
#include "audio/audiostream.h"
#include "audio/mixer.h"
#include "audio/decoders/raw.h"
namespace Video {
enum SmkBlockTypes {
SMK_BLOCK_MONO = 0,
SMK_BLOCK_FULL = 1,
SMK_BLOCK_SKIP = 2,
SMK_BLOCK_FILL = 3
};
/*
* class SmallHuffmanTree
* A Huffman-tree to hold 8-bit values.
*/
class SmallHuffmanTree {
public:
SmallHuffmanTree(Common::BitStream &bs);
uint16 getCode(Common::BitStream &bs);
private:
enum {
SMK_NODE = 0x8000
};
uint16 decodeTree(uint32 prefix, int length);
uint16 _treeSize;
uint16 _tree[511];
uint16 _prefixtree[256];
byte _prefixlength[256];
Common::BitStream &_bs;
};
SmallHuffmanTree::SmallHuffmanTree(Common::BitStream &bs)
: _treeSize(0), _bs(bs) {
uint32 bit = _bs.getBit();
assert(bit);
for (uint16 i = 0; i < 256; ++i)
_prefixtree[i] = _prefixlength[i] = 0;
decodeTree(0, 0);
bit = _bs.getBit();
assert(!bit);
}
uint16 SmallHuffmanTree::decodeTree(uint32 prefix, int length) {
if (!_bs.getBit()) { // Leaf
_tree[_treeSize] = _bs.getBits(8);
if (length <= 8) {
for (int i = 0; i < 256; i += (1 << length)) {
_prefixtree[prefix | i] = _treeSize;
_prefixlength[prefix | i] = length;
}
}
++_treeSize;
return 1;
}
uint16 t = _treeSize++;
if (length == 8) {
_prefixtree[prefix] = t;
_prefixlength[prefix] = 8;
}
uint16 r1 = decodeTree(prefix, length + 1);
_tree[t] = (SMK_NODE | r1);
uint16 r2 = decodeTree(prefix | (1 << length), length + 1);
return r1+r2+1;
}
uint16 SmallHuffmanTree::getCode(Common::BitStream &bs) {
byte peek = bs.peekBits(8);
uint16 *p = &_tree[_prefixtree[peek]];
bs.skip(_prefixlength[peek]);
while (*p & SMK_NODE) {
if (bs.getBit())
p += *p & ~SMK_NODE;
p++;
}
return *p;
}
/*
* class BigHuffmanTree
* A Huffman-tree to hold 16-bit values.
*/
class BigHuffmanTree {
public:
BigHuffmanTree(Common::BitStream &bs, int allocSize);
~BigHuffmanTree();
void reset();
uint32 getCode(Common::BitStream &bs);
private:
enum {
SMK_NODE = 0x80000000
};
uint32 decodeTree(uint32 prefix, int length);
uint32 _treeSize;
uint32 *_tree;
uint32 _last[3];
uint32 _prefixtree[256];
byte _prefixlength[256];
/* Used during construction */
Common::BitStream &_bs;
uint32 _markers[3];
SmallHuffmanTree *_loBytes;
SmallHuffmanTree *_hiBytes;
};
BigHuffmanTree::BigHuffmanTree(Common::BitStream &bs, int allocSize)
: _bs(bs) {
uint32 bit = _bs.getBit();
if (!bit) {
_tree = new uint32[1];
_tree[0] = 0;
_last[0] = _last[1] = _last[2] = 0;
return;
}
for (uint32 i = 0; i < 256; ++i)
_prefixtree[i] = _prefixlength[i] = 0;
_loBytes = new SmallHuffmanTree(_bs);
_hiBytes = new SmallHuffmanTree(_bs);
_markers[0] = _bs.getBits(16);
_markers[1] = _bs.getBits(16);
_markers[2] = _bs.getBits(16);
_last[0] = _last[1] = _last[2] = 0xffffffff;
_treeSize = 0;
_tree = new uint32[allocSize / 4];
decodeTree(0, 0);
bit = _bs.getBit();
assert(!bit);
for (uint32 i = 0; i < 3; ++i) {
if (_last[i] == 0xffffffff) {
_last[i] = _treeSize;
_tree[_treeSize++] = 0;
}
}
delete _loBytes;
delete _hiBytes;
}
BigHuffmanTree::~BigHuffmanTree() {
delete[] _tree;
}
void BigHuffmanTree::reset() {
_tree[_last[0]] = _tree[_last[1]] = _tree[_last[2]] = 0;
}
uint32 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[_treeSize] = v;
if (length <= 8) {
for (int i = 0; i < 256; i += (1 << length)) {
_prefixtree[prefix | i] = _treeSize;
_prefixlength[prefix | i] = length;
}
}
for (int i = 0; i < 3; ++i) {
if (_markers[i] == v) {
_last[i] = _treeSize;
_tree[_treeSize] = 0;
}
}
++_treeSize;
return 1;
}
uint32 t = _treeSize++;
if (length == 8) {
_prefixtree[prefix] = t;
_prefixlength[prefix] = 8;
}
uint32 r1 = decodeTree(prefix, length + 1);
_tree[t] = SMK_NODE | r1;
uint32 r2 = decodeTree(prefix | (1 << length), length + 1);
return r1+r2+1;
}
uint32 BigHuffmanTree::getCode(Common::BitStream &bs) {
byte peek = bs.peekBits(8);
uint32 *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;
}
SmackerDecoder::SmackerDecoder(Audio::Mixer::SoundType soundType) : _soundType(soundType) {
_fileStream = 0;
_firstFrameStart = 0;
_frameTypes = 0;
_frameSizes = 0;
}
SmackerDecoder::~SmackerDecoder() {
close();
}
bool SmackerDecoder::loadStream(Common::SeekableReadStream *stream) {
close();
_fileStream = stream;
// Read in the Smacker header
_header.signature = _fileStream->readUint32BE();
if (_header.signature != MKTAG('S', 'M', 'K', '2') && _header.signature != MKTAG('S', 'M', 'K', '4'))
return false;
uint32 width = _fileStream->readUint32LE();
uint32 height = _fileStream->readUint32LE();
uint32 frameCount = _fileStream->readUint32LE();
int32 frameDelay = _fileStream->readSint32LE();
// frame rate contains 2 digits after the comma, so 1497 is actually 14.97 fps
Common::Rational frameRate;
if (frameDelay > 0)
frameRate = Common::Rational(1000, frameDelay);
else if (frameDelay < 0)
frameRate = Common::Rational(100000, -frameDelay);
else
frameRate = 1000;
// 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();
SmackerVideoTrack *videoTrack = createVideoTrack(width, height, frameCount, frameRate, _header.flags, _header.signature);
addTrack(videoTrack);
// 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();
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 - indicates Huffman + DPCM compression
// * 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
// * bit 27 - indicates Bink RDFT compression
// * bit 26 - indicates Bink DCT compression
// * bits 25-24 - unused
// * bits 23-0 - audio sample rate
uint32 audioInfo = _fileStream->readUint32LE();
_header.audioInfo[i].hasAudio = audioInfo & 0x40000000;
_header.audioInfo[i].is16Bits = audioInfo & 0x20000000;
_header.audioInfo[i].isStereo = audioInfo & 0x10000000;
_header.audioInfo[i].sampleRate = audioInfo & 0xFFFFFF;
if (audioInfo & 0x8000000)
_header.audioInfo[i].compression = kCompressionRDFT;
else if (audioInfo & 0x4000000)
_header.audioInfo[i].compression = kCompressionDCT;
else if (audioInfo & 0x80000000)
_header.audioInfo[i].compression = kCompressionDPCM;
else
_header.audioInfo[i].compression = kCompressionNone;
if (_header.audioInfo[i].hasAudio) {
if (_header.audioInfo[i].compression == kCompressionRDFT || _header.audioInfo[i].compression == kCompressionDCT)
warning("Unhandled Smacker v2 audio compression");
if (i == 0)
addTrack(new SmackerAudioTrack(_header.audioInfo[i], _soundType));
}
}
_header.dummy = _fileStream->readUint32LE();
_frameSizes = new uint32[frameCount];
for (i = 0; i < frameCount; ++i)
_frameSizes[i] = _fileStream->readUint32LE();
_frameTypes = new byte[frameCount];
for (i = 0; i < frameCount; ++i)
_frameTypes[i] = _fileStream->readByte();
byte *huffmanTrees = (byte *) malloc(_header.treesSize);
_fileStream->read(huffmanTrees, _header.treesSize);
Common::BitStream8LSB bs(new Common::MemoryReadStream(huffmanTrees, _header.treesSize, DisposeAfterUse::YES), true);
videoTrack->readTrees(bs, _header.mMapSize, _header.mClrSize, _header.fullSize, _header.typeSize);
_firstFrameStart = _fileStream->pos();
return true;
}
void SmackerDecoder::close() {
VideoDecoder::close();
delete _fileStream;
_fileStream = 0;
delete[] _frameTypes;
_frameTypes = 0;
delete[] _frameSizes;
_frameSizes = 0;
}
bool SmackerDecoder::rewind() {
// Call the parent method to rewind the tracks first
if (!VideoDecoder::rewind())
return false;
// And seek back to where the first frame begins
_fileStream->seek(_firstFrameStart);
return true;
}
void SmackerDecoder::readNextPacket() {
SmackerVideoTrack *videoTrack = (SmackerVideoTrack *)getTrack(0);
if (videoTrack->endOfTrack())
return;
videoTrack->increaseCurFrame();
uint i;
uint32 chunkSize = 0;
uint32 dataSizeUnpacked = 0;
uint32 startPos = _fileStream->pos();
// Check if we got a frame with palette data, and
// call back the virtual setPalette function to set
// the current palette
if (_frameTypes[videoTrack->getCurFrame()] & 1)
videoTrack->unpackPalette(_fileStream);
// Load audio tracks
for (i = 0; i < 7; ++i) {
if (!(_frameTypes[videoTrack->getCurFrame()] & (2 << i)))
continue;
chunkSize = _fileStream->readUint32LE();
chunkSize -= 4; // subtract the first 4 bytes (chunk size)
if (_header.audioInfo[i].compression == kCompressionNone) {
dataSizeUnpacked = chunkSize;
} else {
dataSizeUnpacked = _fileStream->readUint32LE();
chunkSize -= 4; // subtract the next 4 bytes (unpacked data size)
}
handleAudioTrack(i, chunkSize, dataSizeUnpacked);
}
uint32 frameSize = _frameSizes[videoTrack->getCurFrame()] & ~3;
// uint32 remainder = _frameSizes[videoTrack->getCurFrame()] & 3;
if (_fileStream->pos() - startPos > frameSize)
error("Smacker actual frame size exceeds recorded frame size");
uint32 frameDataSize = frameSize - (_fileStream->pos() - startPos);
byte *frameData = (byte *)malloc(frameDataSize + 1);
// Padding to keep the BigHuffmanTrees from reading past the data end
frameData[frameDataSize] = 0x00;
_fileStream->read(frameData, frameDataSize);
Common::BitStream8LSB bs(new Common::MemoryReadStream(frameData, frameDataSize + 1, DisposeAfterUse::YES), true);
videoTrack->decodeFrame(bs);
_fileStream->seek(startPos + frameSize);
}
void SmackerDecoder::handleAudioTrack(byte track, uint32 chunkSize, uint32 unpackedSize) {
if (_header.audioInfo[track].hasAudio && chunkSize > 0 && track == 0) {
// Get the audio track, which start at offset 1 (first track is video)
SmackerAudioTrack *audioTrack = (SmackerAudioTrack *)getTrack(track + 1);
// If it's track 0, play the audio data
byte *soundBuffer = (byte *)malloc(chunkSize + 1);
// Padding to keep the SmallHuffmanTrees from reading past the data end
soundBuffer[chunkSize] = 0x00;
_fileStream->read(soundBuffer, chunkSize);
if (_header.audioInfo[track].compression == kCompressionRDFT || _header.audioInfo[track].compression == kCompressionDCT) {
// TODO: Compressed audio (Bink RDFT/DCT encoded)
free(soundBuffer);
return;
} else if (_header.audioInfo[track].compression == kCompressionDPCM) {
// Compressed audio (Huffman DPCM encoded)
audioTrack->queueCompressedBuffer(soundBuffer, chunkSize + 1, unpackedSize);
free(soundBuffer);
} else {
// Uncompressed audio (PCM)
audioTrack->queuePCM(soundBuffer, chunkSize);
}
} 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);
}
}
SmackerDecoder::SmackerVideoTrack::SmackerVideoTrack(uint32 width, uint32 height, uint32 frameCount, const Common::Rational &frameRate, uint32 flags, uint32 signature) {
_surface = new Graphics::Surface();
_surface->create(width, height * (flags ? 2 : 1), Graphics::PixelFormat::createFormatCLUT8());
_frameCount = frameCount;
_frameRate = frameRate;
_flags = flags;
_signature = signature;
_curFrame = -1;
_dirtyPalette = false;
_MMapTree = _MClrTree = _FullTree = _TypeTree = 0;
memset(_palette, 0, 3 * 256);
}
SmackerDecoder::SmackerVideoTrack::~SmackerVideoTrack() {
_surface->free();
delete _surface;
delete _MMapTree;
delete _MClrTree;
delete _FullTree;
delete _TypeTree;
}
uint16 SmackerDecoder::SmackerVideoTrack::getWidth() const {
return _surface->w;
}
uint16 SmackerDecoder::SmackerVideoTrack::getHeight() const {
return _surface->h;
}
Graphics::PixelFormat SmackerDecoder::SmackerVideoTrack::getPixelFormat() const {
return _surface->format;
}
void SmackerDecoder::SmackerVideoTrack::readTrees(Common::BitStream &bs, uint32 mMapSize, uint32 mClrSize, uint32 fullSize, uint32 typeSize) {
_MMapTree = new BigHuffmanTree(bs, mMapSize);
_MClrTree = new BigHuffmanTree(bs, mClrSize);
_FullTree = new BigHuffmanTree(bs, fullSize);
_TypeTree = new BigHuffmanTree(bs, typeSize);
}
void SmackerDecoder::SmackerVideoTrack::decodeFrame(Common::BitStream &bs) {
_MMapTree->reset();
_MClrTree->reset();
_FullTree->reset();
_TypeTree->reset();
// Height needs to be doubled if we have flags (Y-interlaced or Y-doubled)
uint doubleY = _flags ? 2 : 1;
uint bw = getWidth() / 4;
uint bh = getHeight() / doubleY / 4;
uint stride = getWidth();
uint block = 0, blocks = bw*bh;
byte *out;
uint type, run, j, mode;
uint32 p1, p2, clr, map;
byte hi, lo;
uint i;
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 = (byte *)_surface->pixels + (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 (_signature == MKTAG('S','M','K','2')) {
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 = (byte *)_surface->pixels + (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 = (byte *)_surface->pixels + (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;
}
}
}
void SmackerDecoder::SmackerVideoTrack::unpackPalette(Common::SeekableReadStream *stream) {
uint startPos = stream->pos();
uint32 len = 4 * stream->readByte();
byte *chunk = (byte *)malloc(len);
stream->read(chunk, len);
byte *p = chunk;
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;
}
}
stream->seek(startPos + len);
free(chunk);
_dirtyPalette = true;
}
SmackerDecoder::SmackerAudioTrack::SmackerAudioTrack(const AudioInfo &audioInfo, Audio::Mixer::SoundType soundType) :
_audioInfo(audioInfo), _soundType(soundType) {
_audioStream = Audio::makeQueuingAudioStream(_audioInfo.sampleRate, _audioInfo.isStereo);
}
SmackerDecoder::SmackerAudioTrack::~SmackerAudioTrack() {
delete _audioStream;
}
bool SmackerDecoder::SmackerAudioTrack::rewind() {
delete _audioStream;
_audioStream = Audio::makeQueuingAudioStream(_audioInfo.sampleRate, _audioInfo.isStereo);
return true;
}
Audio::AudioStream *SmackerDecoder::SmackerAudioTrack::getAudioStream() const {
return _audioStream;
}
void SmackerDecoder::SmackerAudioTrack::queueCompressedBuffer(byte *buffer, uint32 bufferSize, uint32 unpackedSize) {
Common::BitStream8LSB audioBS(new Common::MemoryReadStream(buffer, bufferSize), true);
bool dataPresent = audioBS.getBit();
if (!dataPresent)
return;
bool isStereo = audioBS.getBit();
assert(isStereo == _audioInfo.isStereo);
bool is16Bits = audioBS.getBit();
assert(is16Bits == _audioInfo.is16Bits);
int numBytes = 1 * (isStereo ? 2 : 1) * (is16Bits ? 2 : 1);
byte *unpackedBuffer = (byte *)malloc(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) {
if (is16Bits) {
bases[1] = SWAP_BYTES_16(audioBS.getBits(16));
} else {
bases[1] = audioBS.getBits(8);
}
}
if (is16Bits) {
bases[0] = SWAP_BYTES_16(audioBS.getBits(16));
} else {
bases[0] = audioBS.getBits(8);
}
// 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++) {
byte lo = audioTrees[k * 2]->getCode(audioBS);
byte hi = audioTrees[k * 2 + 1]->getCode(audioBS);
bases[k] += (int16) (lo | (hi << 8));
WRITE_BE_UINT16(curPointer, bases[k]);
curPointer += 2;
curPos += 2;
}
}
}
for (int k = 0; k < numBytes; k++)
delete audioTrees[k];
queuePCM(unpackedBuffer, unpackedSize);
}
void SmackerDecoder::SmackerAudioTrack::queuePCM(byte *buffer, uint32 bufferSize) {
byte flags = 0;
if (_audioInfo.is16Bits)
flags |= Audio::FLAG_16BITS;
if (_audioInfo.isStereo)
flags |= Audio::FLAG_STEREO;
_audioStream->queueBuffer(buffer, bufferSize, DisposeAfterUse::YES, flags);
}
SmackerDecoder::SmackerVideoTrack *SmackerDecoder::createVideoTrack(uint32 width, uint32 height, uint32 frameCount, const Common::Rational &frameRate, uint32 flags, uint32 signature) const {
return new SmackerVideoTrack(width, height, frameCount, frameRate, flags, signature);
}
} // End of namespace Video