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/*
* Bitmap Brothers JV demuxer
* Copyright (c) 2005, 2011 Peter Ross <pross@xvid.org>
*
* 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
* Bitmap Brothers JV demuxer
* @author Peter Ross <pross@xvid.org>
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define JV_PREAMBLE_SIZE 5
typedef struct {
int audio_size; /** audio packet size (bytes) */
int video_size; /** video packet size (bytes) */
int palette_size; /** palette size (bytes) */
int video_type; /** per-frame video compression type */
} JVFrame;
typedef struct {
JVFrame *frames;
enum {
JV_AUDIO = 0,
JV_VIDEO,
JV_PADDING
} state;
int64_t pts;
} JVDemuxContext;
#define MAGIC " Compression by John M Phillips Copyright (C) 1995 The Bitmap Brothers Ltd."
static int read_probe(AVProbeData *pd)
{
if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) <= pd->buf_size - 4 &&
!memcmp(pd->buf + 4, MAGIC, strlen(MAGIC)))
return AVPROBE_SCORE_MAX;
return 0;
}
static int read_header(AVFormatContext *s)
{
JVDemuxContext *jv = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *vst, *ast;
int64_t audio_pts = 0;
int64_t offset;
int i;
avio_skip(pb, 80);
ast = avformat_new_stream(s, NULL);
vst = avformat_new_stream(s, NULL);
if (!ast || !vst)
return AVERROR(ENOMEM);
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = AV_CODEC_ID_JV;
vst->codec->codec_tag = 0; /* no fourcc */
vst->codec->width = avio_rl16(pb);
vst->codec->height = avio_rl16(pb);
vst->duration =
vst->nb_frames =
ast->nb_index_entries = avio_rl16(pb);
avpriv_set_pts_info(vst, 64, avio_rl16(pb), 1000);
avio_skip(pb, 4);
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->codec_id = AV_CODEC_ID_PCM_U8;
ast->codec->codec_tag = 0; /* no fourcc */
ast->codec->sample_rate = avio_rl16(pb);
ast->codec->channels = 1;
avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
avio_skip(pb, 10);
ast->index_entries = av_malloc(ast->nb_index_entries * sizeof(*ast->index_entries));
if (!ast->index_entries)
return AVERROR(ENOMEM);
jv->frames = av_malloc(ast->nb_index_entries * sizeof(JVFrame));
if (!jv->frames)
return AVERROR(ENOMEM);
offset = 0x68 + ast->nb_index_entries * 16;
for(i = 0; i < ast->nb_index_entries; i++) {
AVIndexEntry *e = ast->index_entries + i;
JVFrame *jvf = jv->frames + i;
/* total frame size including audio, video, palette data and padding */
e->size = avio_rl32(pb);
e->timestamp = i;
e->pos = offset;
offset += e->size;
jvf->audio_size = avio_rl32(pb);
jvf->video_size = avio_rl32(pb);
jvf->palette_size = avio_r8(pb) ? 768 : 0;
jvf->video_size = FFMIN(FFMAX(jvf->video_size, 0),
INT_MAX - JV_PREAMBLE_SIZE - jvf->palette_size);
if (avio_r8(pb))
av_log(s, AV_LOG_WARNING, "unsupported audio codec\n");
jvf->video_type = avio_r8(pb);
avio_skip(pb, 1);
e->timestamp = jvf->audio_size ? audio_pts : AV_NOPTS_VALUE;
audio_pts += jvf->audio_size;
e->flags = jvf->video_type != 1 ? AVINDEX_KEYFRAME : 0;
}
jv->state = JV_AUDIO;
return 0;
}
static int read_packet(AVFormatContext *s, AVPacket *pkt)
{
JVDemuxContext *jv = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *ast = s->streams[0];
while (!url_feof(s->pb) && jv->pts < ast->nb_index_entries) {
const AVIndexEntry *e = ast->index_entries + jv->pts;
const JVFrame *jvf = jv->frames + jv->pts;
switch(jv->state) {
case JV_AUDIO:
jv->state++;
if (jvf->audio_size ) {
if (av_get_packet(s->pb, pkt, jvf->audio_size) < 0)
return AVERROR(ENOMEM);
pkt->stream_index = 0;
pkt->pts = e->timestamp;
pkt->flags |= AV_PKT_FLAG_KEY;
return 0;
}
case JV_VIDEO:
jv->state++;
if (jvf->video_size || jvf->palette_size) {
int size = jvf->video_size + jvf->palette_size;
if (av_new_packet(pkt, size + JV_PREAMBLE_SIZE))
return AVERROR(ENOMEM);
AV_WL32(pkt->data, jvf->video_size);
pkt->data[4] = jvf->video_type;
if ((size = avio_read(pb, pkt->data + JV_PREAMBLE_SIZE, size)) < 0)
return AVERROR(EIO);
pkt->size = size + JV_PREAMBLE_SIZE;
pkt->stream_index = 1;
pkt->pts = jv->pts;
if (jvf->video_type != 1)
pkt->flags |= AV_PKT_FLAG_KEY;
return 0;
}
case JV_PADDING:
avio_skip(pb, FFMAX(e->size - jvf->audio_size - jvf->video_size
- jvf->palette_size, 0));
jv->state = JV_AUDIO;
jv->pts++;
}
}
return AVERROR(EIO);
}
static int read_seek(AVFormatContext *s, int stream_index,
int64_t ts, int flags)
{
JVDemuxContext *jv = s->priv_data;
AVStream *ast = s->streams[0];
int i;
if (flags & (AVSEEK_FLAG_BYTE|AVSEEK_FLAG_FRAME))
return AVERROR(ENOSYS);
switch(stream_index) {
case 0:
i = av_index_search_timestamp(ast, ts, flags);
break;
case 1:
i = ts;
break;
default:
return 0;
}
if (i < 0 || i >= ast->nb_index_entries)
return 0;
if (avio_seek(s->pb, ast->index_entries[i].pos, SEEK_SET) < 0)
return -1;
jv->state = JV_AUDIO;
jv->pts = i;
return 0;
}
static int read_close(AVFormatContext *s)
{
JVDemuxContext *jv = s->priv_data;
av_freep(&jv->frames);
return 0;
}
AVInputFormat ff_jv_demuxer = {
.name = "jv",
.long_name = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV"),
.priv_data_size = sizeof(JVDemuxContext),
.read_probe = read_probe,
.read_header = read_header,
.read_packet = read_packet,
.read_seek = read_seek,
.read_close = read_close,
};
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