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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.
*
* $URL$
* $Id$
*
*/
#include "graphics/video/codecs/cinepak.h"
#include "common/system.h"
// Code here partially based off of ffmpeg ;)
namespace Graphics {
// Convert a color from YUV to RGB colorspace, Cinepak style.
inline static void CPYUV2RGB(byte y, byte u, byte v, byte &r, byte &g, byte &b) {
r = CLIP<int>(y + 2 * (v - 128), 0, 255);
g = CLIP<int>(y - (u - 128) / 2 - (v - 128), 0, 255);
b = CLIP<int>(y + 2 * (u - 128), 0, 255);
}
#define PUT_PIXEL(offset, lum, u, v) \
CPYUV2RGB(lum, u, v, r, g, b); \
if (_pixelFormat.bytesPerPixel == 2) \
*((uint16 *)_curFrame.surface->pixels + offset) = _pixelFormat.RGBToColor(r, g, b); \
else \
*((uint32 *)_curFrame.surface->pixels + offset) = _pixelFormat.RGBToColor(r, g, b)
CinepakDecoder::CinepakDecoder() : Codec() {
_curFrame.surface = NULL;
_curFrame.strips = NULL;
_y = 0;
_pixelFormat = g_system->getScreenFormat();
}
CinepakDecoder::~CinepakDecoder() {
if (_curFrame.surface) {
_curFrame.surface->free();
delete _curFrame.surface;
}
delete[] _curFrame.strips;
}
Surface *CinepakDecoder::decodeImage(Common::SeekableReadStream *stream) {
_curFrame.flags = stream->readByte();
_curFrame.length = (stream->readByte() << 16) + stream->readUint16BE();
_curFrame.width = stream->readUint16BE();
_curFrame.height = stream->readUint16BE();
_curFrame.stripCount = stream->readUint16BE();
if (_curFrame.strips == NULL)
_curFrame.strips = new CinepakStrip[_curFrame.stripCount];
debug (4, "Cinepak Frame: Width = %d, Height = %d, Strip Count = %d", _curFrame.width, _curFrame.height, _curFrame.stripCount);
// Borrowed from FFMPEG. This should cut out the extra data Cinepak for Sega has (which is useless).
// The theory behind this is that this is here to confuse standard Cinepak decoders. But, we won't let that happen! ;)
if (_curFrame.length != (uint32)stream->size()) {
if (stream->readUint16BE() == 0xFE00)
stream->readUint32BE();
}
if (!_curFrame.surface) {
_curFrame.surface = new Surface();
_curFrame.surface->create(_curFrame.width, _curFrame.height, _pixelFormat.bytesPerPixel);
}
// Reset the y variable.
_y = 0;
for (uint16 i = 0; i < _curFrame.stripCount; i++) {
if (i > 0 && !(_curFrame.flags & 1)) { // Use codebooks from last strip
for (uint16 j = 0; j < 256; j++) {
_curFrame.strips[i].v1_codebook[j] = _curFrame.strips[i - 1].v1_codebook[j];
_curFrame.strips[i].v4_codebook[j] = _curFrame.strips[i - 1].v4_codebook[j];
}
}
_curFrame.strips[i].id = stream->readUint16BE();
_curFrame.strips[i].length = stream->readUint16BE() - 12; // Subtract the 12 byte header
_curFrame.strips[i].rect.top = _y; stream->readUint16BE(); // Ignore, substitute with our own.
_curFrame.strips[i].rect.left = 0; stream->readUint16BE(); // Ignore, substitute with our own
_curFrame.strips[i].rect.bottom = _y + stream->readUint16BE();
_curFrame.strips[i].rect.right = _curFrame.width; stream->readUint16BE(); // Ignore, substitute with our own
// Sanity check. Because Cinepak is based on 4x4 blocks, the width and height of each strip needs to be divisible by 4.
assert(!(_curFrame.strips[i].rect.width() % 4) && !(_curFrame.strips[i].rect.height() % 4));
uint32 pos = stream->pos();
while ((uint32)stream->pos() < (pos + _curFrame.strips[i].length) && !stream->eos()) {
byte chunkID = stream->readByte();
if (stream->eos())
break;
// Chunk Size is 24-bit, ignore the first 4 bytes
uint32 chunkSize = stream->readByte() << 16;
chunkSize += stream->readUint16BE() - 4;
int32 startPos = stream->pos();
switch (chunkID) {
case 0x20:
case 0x21:
case 0x24:
case 0x25:
loadCodebook(stream, i, 4, chunkID, chunkSize);
break;
case 0x22:
case 0x23:
case 0x26:
case 0x27:
loadCodebook(stream, i, 1, chunkID, chunkSize);
break;
case 0x30:
case 0x31:
case 0x32:
decodeVectors(stream, i, chunkID, chunkSize);
break;
default:
warning("Unknown Cinepak chunk ID %02x", chunkID);
return _curFrame.surface;
}
if (stream->pos() != startPos + (int32)chunkSize)
stream->seek(startPos + chunkSize);
}
_y = _curFrame.strips[i].rect.bottom;
}
return _curFrame.surface;
}
void CinepakDecoder::loadCodebook(Common::SeekableReadStream *stream, uint16 strip, byte codebookType, byte chunkID, uint32 chunkSize) {
CinepakCodebook *codebook = (codebookType == 1) ? _curFrame.strips[strip].v1_codebook : _curFrame.strips[strip].v4_codebook;
int32 startPos = stream->pos();
uint32 flag = 0, mask = 0;
for (uint16 i = 0; i < 256; i++) {
if ((chunkID & 0x01) && !(mask >>= 1)) {
if ((stream->pos() - startPos + 4) > (int32)chunkSize)
break;
flag = stream->readUint32BE();
mask = 0x80000000;
}
if (!(chunkID & 0x01) || (flag & mask)) {
byte n = (chunkID & 0x04) ? 4 : 6;
if ((stream->pos() - startPos + n) > (int32)chunkSize)
break;
for (byte j = 0; j < 4; j++)
codebook[i].y[j] = stream->readByte();
if (n == 6) {
codebook[i].u = stream->readByte() + 128;
codebook[i].v = stream->readByte() + 128;
} else {
// This codebook type indicates either greyscale or
// palettized video. We don't handle palettized video
// currently.
codebook[i].u = 128;
codebook[i].v = 128;
}
}
}
}
void CinepakDecoder::decodeVectors(Common::SeekableReadStream *stream, uint16 strip, byte chunkID, uint32 chunkSize) {
uint32 flag = 0, mask = 0;
uint32 iy[4];
int32 startPos = stream->pos();
byte r = 0, g = 0, b = 0;
for (uint16 y = _curFrame.strips[strip].rect.top; y < _curFrame.strips[strip].rect.bottom; y += 4) {
iy[0] = _curFrame.strips[strip].rect.left + y * _curFrame.width;
iy[1] = iy[0] + _curFrame.width;
iy[2] = iy[1] + _curFrame.width;
iy[3] = iy[2] + _curFrame.width;
for (uint16 x = _curFrame.strips[strip].rect.left; x < _curFrame.strips[strip].rect.right; x += 4) {
if ((chunkID & 0x01) && !(mask >>= 1)) {
if ((stream->pos() - startPos + 4) > (int32)chunkSize)
return;
flag = stream->readUint32BE();
mask = 0x80000000;
}
if (!(chunkID & 0x01) || (flag & mask)) {
if (!(chunkID & 0x02) && !(mask >>= 1)) {
if ((stream->pos() - startPos + 4) > (int32)chunkSize)
return;
flag = stream->readUint32BE();
mask = 0x80000000;
}
if ((chunkID & 0x02) || (~flag & mask)) {
if ((stream->pos() - startPos + 1) > (int32)chunkSize)
return;
// Get the codebook
CinepakCodebook codebook = _curFrame.strips[strip].v1_codebook[stream->readByte()];
PUT_PIXEL(iy[0] + 0, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[0] + 1, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 0, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 1, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[0] + 2, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[0] + 3, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 2, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 3, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 0, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 1, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 0, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 1, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 2, codebook.y[3], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 3, codebook.y[3], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 2, codebook.y[3], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 3, codebook.y[3], codebook.u, codebook.v);
} else if (flag & mask) {
if ((stream->pos() - startPos + 4) > (int32)chunkSize)
return;
CinepakCodebook codebook = _curFrame.strips[strip].v4_codebook[stream->readByte()];
PUT_PIXEL(iy[0] + 0, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[0] + 1, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 0, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 1, codebook.y[3], codebook.u, codebook.v);
codebook = _curFrame.strips[strip].v4_codebook[stream->readByte()];
PUT_PIXEL(iy[0] + 2, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[0] + 3, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 2, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[1] + 3, codebook.y[3], codebook.u, codebook.v);
codebook = _curFrame.strips[strip].v4_codebook[stream->readByte()];
PUT_PIXEL(iy[2] + 0, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 1, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 0, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 1, codebook.y[3], codebook.u, codebook.v);
codebook = _curFrame.strips[strip].v4_codebook[stream->readByte()];
PUT_PIXEL(iy[2] + 2, codebook.y[0], codebook.u, codebook.v);
PUT_PIXEL(iy[2] + 3, codebook.y[1], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 2, codebook.y[2], codebook.u, codebook.v);
PUT_PIXEL(iy[3] + 3, codebook.y[3], codebook.u, codebook.v);
}
}
for (byte i = 0; i < 4; i++)
iy[i] += 4;
}
}
}
} // End of namespace Graphics
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