scummvm/image/codecs/mpeg.cpp

108 lines
2.9 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.
*
*/
#include "common/debug.h"
#include "common/stream.h"
#include "common/system.h"
#include "common/textconsole.h"
#include "graphics/surface.h"
#include "graphics/yuv_to_rgb.h"
#include "image/codecs/mpeg.h"
namespace Image {
MPEGDecoder::MPEGDecoder() : Codec() {
_pixelFormat = g_system->getScreenFormat();
_surface = 0;
_mpegDecoder = mpeg2_init();
if (!_mpegDecoder)
error("Could not initialize libmpeg2");
_mpegInfo = mpeg2_info(_mpegDecoder);
}
MPEGDecoder::~MPEGDecoder() {
mpeg2_close(_mpegDecoder);
if (_surface) {
_surface->free();
delete _surface;
}
}
const Graphics::Surface *MPEGDecoder::decodeFrame(Common::SeekableReadStream &stream) {
uint32 framePeriod;
decodePacket(stream, framePeriod);
return _surface;
}
bool MPEGDecoder::decodePacket(Common::SeekableReadStream &packet, uint32 &framePeriod, Graphics::Surface *dst) {
// Decode as much as we can out of this packet
uint32 size = 0xFFFFFFFF;
mpeg2_state_t state;
bool foundFrame = false;
framePeriod = 0;
do {
state = mpeg2_parse(_mpegDecoder);
switch (state) {
case STATE_BUFFER:
size = packet.read(_buffer, BUFFER_SIZE);
mpeg2_buffer(_mpegDecoder, _buffer, _buffer + size);
break;
case STATE_SLICE:
case STATE_END:
if (_mpegInfo->display_fbuf) {
foundFrame = true;
const mpeg2_sequence_t *sequence = _mpegInfo->sequence;
framePeriod += sequence->frame_period;
if (!dst) {
// If no destination is specified, use our internal storage
if (!_surface) {
_surface = new Graphics::Surface();
_surface->create(sequence->picture_width, sequence->picture_height, _pixelFormat);
}
dst = _surface;
}
YUVToRGBMan.convert420(dst, Graphics::YUVToRGBManager::kScaleITU, _mpegInfo->display_fbuf->buf[0],
_mpegInfo->display_fbuf->buf[1], _mpegInfo->display_fbuf->buf[2], sequence->picture_width,
sequence->picture_height, sequence->width, sequence->chroma_width);
}
break;
default:
break;
}
} while (size != 0);
return foundFrame;
}
} // End of namespace Image