ffmpeg/libavcodec/libdiracdec.c

210 lines
6.7 KiB
C

/*
* Dirac decoder support via libdirac library
* Copyright (c) 2005 BBC, Andrew Kennedy <dirac at rd dot bbc dot co dot uk>
* Copyright (c) 2006-2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Dirac decoder support via libdirac library; more details about the Dirac
* project can be found at http://dirac.sourceforge.net/.
* The libdirac_decoder library implements Dirac specification version 2.2
* (http://dirac.sourceforge.net/specification.html).
*/
#include "libavcore/imgutils.h"
#include "libdirac.h"
#undef NDEBUG
#include <assert.h>
#include <libdirac_decoder/dirac_parser.h>
/** contains a single frame returned from Dirac */
typedef struct FfmpegDiracDecoderParams {
/** decoder handle */
dirac_decoder_t* p_decoder;
/** buffer to hold decoded frame */
unsigned char* p_out_frame_buf;
} FfmpegDiracDecoderParams;
/**
* returns FFmpeg chroma format
*/
static enum PixelFormat GetFfmpegChromaFormat(dirac_chroma_t dirac_pix_fmt)
{
int num_formats = sizeof(ffmpeg_dirac_pixel_format_map) /
sizeof(ffmpeg_dirac_pixel_format_map[0]);
int idx;
for (idx = 0; idx < num_formats; ++idx)
if (ffmpeg_dirac_pixel_format_map[idx].dirac_pix_fmt == dirac_pix_fmt)
return ffmpeg_dirac_pixel_format_map[idx].ff_pix_fmt;
return PIX_FMT_NONE;
}
static av_cold int libdirac_decode_init(AVCodecContext *avccontext)
{
FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
p_dirac_params->p_decoder = dirac_decoder_init(avccontext->debug);
if (!p_dirac_params->p_decoder)
return -1;
return 0;
}
static int libdirac_decode_frame(AVCodecContext *avccontext,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
AVPicture *picture = data;
AVPicture pic;
int pict_size;
unsigned char *buffer[3];
*data_size = 0;
if (buf_size > 0) {
/* set data to decode into buffer */
dirac_buffer(p_dirac_params->p_decoder, buf, buf + buf_size);
if ((buf[4] & 0x08) == 0x08 && (buf[4] & 0x03))
avccontext->has_b_frames = 1;
}
while (1) {
/* parse data and process result */
DecoderState state = dirac_parse(p_dirac_params->p_decoder);
switch (state) {
case STATE_BUFFER:
return buf_size;
case STATE_SEQUENCE:
{
/* tell FFmpeg about sequence details */
dirac_sourceparams_t *src_params = &p_dirac_params->p_decoder->src_params;
if (av_image_check_size(src_params->width, src_params->height,
0, avccontext) < 0) {
av_log(avccontext, AV_LOG_ERROR, "Invalid dimensions (%dx%d)\n",
src_params->width, src_params->height);
avccontext->height = avccontext->width = 0;
return -1;
}
avccontext->height = src_params->height;
avccontext->width = src_params->width;
avccontext->pix_fmt = GetFfmpegChromaFormat(src_params->chroma);
if (avccontext->pix_fmt == PIX_FMT_NONE) {
av_log(avccontext, AV_LOG_ERROR,
"Dirac chroma format %d not supported currently\n",
src_params->chroma);
return -1;
}
avccontext->time_base.den = src_params->frame_rate.numerator;
avccontext->time_base.num = src_params->frame_rate.denominator;
/* calculate output dimensions */
avpicture_fill(&pic, NULL, avccontext->pix_fmt,
avccontext->width, avccontext->height);
pict_size = avpicture_get_size(avccontext->pix_fmt,
avccontext->width,
avccontext->height);
/* allocate output buffer */
if (!p_dirac_params->p_out_frame_buf)
p_dirac_params->p_out_frame_buf = av_malloc(pict_size);
buffer[0] = p_dirac_params->p_out_frame_buf;
buffer[1] = p_dirac_params->p_out_frame_buf +
pic.linesize[0] * avccontext->height;
buffer[2] = buffer[1] +
pic.linesize[1] * src_params->chroma_height;
/* tell Dirac about output destination */
dirac_set_buf(p_dirac_params->p_decoder, buffer, NULL);
break;
}
case STATE_SEQUENCE_END:
break;
case STATE_PICTURE_AVAIL:
/* fill picture with current buffer data from Dirac */
avpicture_fill(picture, p_dirac_params->p_out_frame_buf,
avccontext->pix_fmt,
avccontext->width, avccontext->height);
*data_size = sizeof(AVPicture);
return buf_size;
case STATE_INVALID:
return -1;
default:
break;
}
}
return buf_size;
}
static av_cold int libdirac_decode_close(AVCodecContext *avccontext)
{
FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
dirac_decoder_close(p_dirac_params->p_decoder);
av_freep(&p_dirac_params->p_out_frame_buf);
return 0;
}
static void libdirac_flush(AVCodecContext *avccontext)
{
/* Got a seek request. We will need free memory held in the private
* context and free the current Dirac decoder handle and then open
* a new decoder handle. */
libdirac_decode_close(avccontext);
libdirac_decode_init(avccontext);
return;
}
AVCodec libdirac_decoder = {
"libdirac",
AVMEDIA_TYPE_VIDEO,
CODEC_ID_DIRAC,
sizeof(FfmpegDiracDecoderParams),
libdirac_decode_init,
NULL,
libdirac_decode_close,
libdirac_decode_frame,
CODEC_CAP_DELAY,
.flush = libdirac_flush,
.long_name = NULL_IF_CONFIG_SMALL("libdirac Dirac 2.2"),
};