ffmpeg/libavformat/dv.c

148 lines
3.3 KiB
C

/*
* Raw DV format
* Copyright (c) 2002 Fabrice Bellard.
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "avformat.h"
#define NTSC_FRAME_SIZE 120000
#define PAL_FRAME_SIZE 144000
typedef struct DVDemuxContext {
int is_audio;
uint8_t buf[PAL_FRAME_SIZE];
int size;
} DVDemuxContext;
/* raw input */
static int dv_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
AVStream *vst, *ast;
DVDemuxContext *c = s->priv_data;
vst = av_new_stream(s, 0);
if (!vst)
return AVERROR_NOMEM;
vst->codec.codec_type = CODEC_TYPE_VIDEO;
vst->codec.codec_id = CODEC_ID_DVVIDEO;
ast = av_new_stream(s, 1);
if (!ast)
return AVERROR_NOMEM;
ast->codec.codec_type = CODEC_TYPE_AUDIO;
ast->codec.codec_id = CODEC_ID_DVAUDIO;
ast->codec.channels = 2;
c->is_audio = 0;
return 0;
}
static void __destruct_pkt(struct AVPacket *pkt)
{
pkt->data = NULL; pkt->size = 0;
return;
}
static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, dsf;
DVDemuxContext *c = s->priv_data;
if (!c->is_audio) {
ret = get_buffer(&s->pb, c->buf, 4);
if (ret <= 0)
return -EIO;
dsf = c->buf[3] & 0x80;
if (!dsf)
c->size = NTSC_FRAME_SIZE;
else
c->size = PAL_FRAME_SIZE;
ret = get_buffer(&s->pb, c->buf + 4, c->size - 4);
if (ret <= 0)
return -EIO;
}
av_init_packet(pkt);
pkt->destruct = __destruct_pkt;
pkt->data = c->buf;
pkt->size = c->size;
pkt->stream_index = c->is_audio;
c->is_audio = !c->is_audio;
return c->size;
}
static int dv_read_close(AVFormatContext *s)
{
return 0;
}
static AVInputFormat dv_iformat = {
"dv",
"DV video format",
sizeof(DVDemuxContext),
NULL,
dv_read_header,
dv_read_packet,
dv_read_close,
.extensions = "dv",
};
#if 0
int dv_write_header(struct AVFormatContext *s)
{
return 0;
}
int dv_write_packet(struct AVFormatContext *s,
int stream_index,
unsigned char *buf, int size, int force_pts)
{
put_buffer(&s->pb, buf, size);
put_flush_packet(&s->pb);
return 0;
}
int dv_write_trailer(struct AVFormatContext *s)
{
return 0;
}
AVOutputFormat dv_oformat = {
"dv",
"DV video format",
NULL,
"dv",
0,
CODEC_ID_DVVIDEO,
CODEC_ID_DVAUDIO,
dv_write_header,
dv_write_packet,
dv_write_trailer,
};
#endif
int dv_init(void)
{
av_register_input_format(&dv_iformat);
// av_register_output_format(&dv_oformat);
return 0;
}