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FFmpeg/libavformat/jvdec.c
Andreas Rheinhardt 2882286a08 avformat/jvdec: Make sizeof(JVFrame) smaller to save memory
Reviewed-by: Peter Ross <pross@xvid.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2021-09-26 01:43:18 +02:00

265 lines
8.0 KiB
C

/*
* 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/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define JV_PREAMBLE_SIZE 5
typedef struct JVFrame {
int audio_size; /**< audio packet size (bytes) */
int video_size; /**< video packet size (bytes) */
uint16_t palette_size; /**< palette size (bytes) */
uint8_t video_type; /**< per-frame video compression type */
} JVFrame;
typedef struct JVDemuxContext {
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(const AVProbeData *pd)
{
if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) + 4 <= pd->buf_size &&
!memcmp(pd->buf + 4, MAGIC, strlen(MAGIC)))
return AVPROBE_SCORE_MAX;
return 0;
}
static int read_close(AVFormatContext *s)
{
JVDemuxContext *jv = s->priv_data;
av_freep(&jv->frames);
return 0;
}
static int read_header(AVFormatContext *s)
{
JVDemuxContext *jv = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *vst, *ast;
FFStream *asti;
int64_t audio_pts = 0;
int64_t offset;
avio_skip(pb, 80);
ast = avformat_new_stream(s, NULL);
vst = avformat_new_stream(s, NULL);
if (!ast || !vst)
return AVERROR(ENOMEM);
asti = ffstream(ast);
vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codecpar->codec_id = AV_CODEC_ID_JV;
vst->codecpar->codec_tag = 0; /* no fourcc */
vst->codecpar->width = avio_rl16(pb);
vst->codecpar->height = avio_rl16(pb);
vst->duration =
vst->nb_frames =
asti->nb_index_entries = avio_rl16(pb);
avpriv_set_pts_info(vst, 64, avio_rl16(pb), 1000);
avio_skip(pb, 4);
ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
ast->codecpar->codec_tag = 0; /* no fourcc */
ast->codecpar->sample_rate = avio_rl16(pb);
ast->codecpar->channels = 1;
ast->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
avio_skip(pb, 10);
asti->index_entries = av_malloc(asti->nb_index_entries *
sizeof(*asti->index_entries));
if (!asti->index_entries)
return AVERROR(ENOMEM);
jv->frames = av_malloc(asti->nb_index_entries * sizeof(*jv->frames));
if (!jv->frames)
return AVERROR(ENOMEM);
offset = 0x68 + asti->nb_index_entries * 16;
for (int i = 0; i < asti->nb_index_entries; i++) {
AVIndexEntry *e = asti->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;
if ((jvf->video_size | jvf->audio_size) & ~0xFFFFFF ||
e->size - jvf->audio_size
- jvf->video_size
- jvf->palette_size < 0) {
if (s->error_recognition & AV_EF_EXPLODE)
return AVERROR_INVALIDDATA;
jvf->audio_size =
jvf->video_size =
jvf->palette_size = 0;
}
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];
FFStream *const asti = ffstream(ast);
int ret;
while (!avio_feof(s->pb) && jv->pts < asti->nb_index_entries) {
const AVIndexEntry *const e = asti->index_entries + jv->pts;
const JVFrame *jvf = jv->frames + jv->pts;
switch (jv->state) {
case JV_AUDIO:
jv->state++;
if (jvf->audio_size) {
if ((ret = av_get_packet(s->pb, pkt, jvf->audio_size)) < 0)
return ret;
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 ((ret = av_new_packet(pkt, size + JV_PREAMBLE_SIZE)) < 0)
return ret;
AV_WL32(pkt->data, jvf->video_size);
pkt->data[4] = jvf->video_type;
ret = avio_read(pb, pkt->data + JV_PREAMBLE_SIZE, size);
if (ret < 0)
return ret;
if (ret < size) {
memset(pkt->data + JV_PREAMBLE_SIZE + ret, 0,
AV_INPUT_BUFFER_PADDING_SIZE);
pkt->flags |= AV_PKT_FLAG_CORRUPT;
}
pkt->size = ret + 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++;
}
}
if (s->pb->eof_reached)
return AVERROR_EOF;
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];
FFStream *const asti = ffstream(ast);
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 >= asti->nb_index_entries)
return 0;
if (avio_seek(s->pb, asti->index_entries[i].pos, SEEK_SET) < 0)
return -1;
jv->state = JV_AUDIO;
jv->pts = i;
return 0;
}
const AVInputFormat ff_jv_demuxer = {
.name = "jv",
.long_name = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV"),
.priv_data_size = sizeof(JVDemuxContext),
.flags_internal = FF_FMT_INIT_CLEANUP,
.read_probe = read_probe,
.read_header = read_header,
.read_packet = read_packet,
.read_seek = read_seek,
.read_close = read_close,
};