FFmpeg/libavformat/bink.c
Anton Khirnov 9200514ad8 lavf: replace AVStream.codec with AVStream.codecpar
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.

In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.

There are multiple important problems with this approach:
    - the fields in AVCodecContext are in general one of
        * stream parameters
        * codec options
        * codec state
      However, it's not clear which ones are which. It is consequently
      unclear which fields are a demuxer allowed to set or a muxer allowed to
      read. This leads to erratic behaviour depending on whether decoding or
      encoding is being performed or not (and whether it uses the AVStream
      embedded codec context).
    - various synchronization issues arising from the fact that the same
      context is used by several different APIs (muxers/demuxers,
      parsers, bitstream filters and encoders/decoders) simultaneously, with
      there being no clear rules for who can modify what and the different
      processes being typically delayed with respect to each other.
    - avformat_find_stream_info() making it necessary to support opening
      and closing a single codec context multiple times, thus
      complicating the semantics of freeing various allocated objects in the
      codec context.

Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
2016-02-23 17:01:58 +01:00

292 lines
9.2 KiB
C

/*
* Bink demuxer
* Copyright (c) 2008-2010 Peter Ross (pross@xvid.org)
* Copyright (c) 2009 Daniel Verkamp (daniel@drv.nu)
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Bink demuxer
*
* Technical details here:
* http://wiki.multimedia.cx/index.php?title=Bink_Container
*/
#include <inttypes.h>
#include "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
enum BinkAudFlags {
BINK_AUD_16BITS = 0x4000, ///< prefer 16-bit output
BINK_AUD_STEREO = 0x2000,
BINK_AUD_USEDCT = 0x1000,
};
#define BINK_EXTRADATA_SIZE 1
#define BINK_MAX_AUDIO_TRACKS 256
#define BINK_MAX_WIDTH 7680
#define BINK_MAX_HEIGHT 4800
typedef struct BinkDemuxContext {
uint32_t file_size;
uint32_t num_audio_tracks;
int current_track; ///< audio track to return in next packet
int64_t video_pts;
int64_t audio_pts[BINK_MAX_AUDIO_TRACKS];
uint32_t remain_packet_size;
} BinkDemuxContext;
static int probe(AVProbeData *p)
{
const uint8_t *b = p->buf;
if ( b[0] == 'B' && b[1] == 'I' && b[2] == 'K' &&
(b[3] == 'b' || b[3] == 'f' || b[3] == 'g' || b[3] == 'h' || b[3] == 'i') &&
AV_RL32(b+8) > 0 && // num_frames
AV_RL32(b+20) > 0 && AV_RL32(b+20) <= BINK_MAX_WIDTH &&
AV_RL32(b+24) > 0 && AV_RL32(b+24) <= BINK_MAX_HEIGHT &&
AV_RL32(b+28) > 0 && AV_RL32(b+32) > 0) // fps num,den
return AVPROBE_SCORE_MAX;
return 0;
}
static int read_header(AVFormatContext *s)
{
BinkDemuxContext *bink = s->priv_data;
AVIOContext *pb = s->pb;
uint32_t fps_num, fps_den;
AVStream *vst, *ast;
unsigned int i;
uint32_t pos, next_pos;
uint16_t flags;
int keyframe;
vst = avformat_new_stream(s, NULL);
if (!vst)
return AVERROR(ENOMEM);
vst->codecpar->codec_tag = avio_rl32(pb);
bink->file_size = avio_rl32(pb) + 8;
vst->duration = avio_rl32(pb);
if (vst->duration > 1000000) {
av_log(s, AV_LOG_ERROR, "invalid header: more than 1000000 frames\n");
return AVERROR(EIO);
}
if (avio_rl32(pb) > bink->file_size) {
av_log(s, AV_LOG_ERROR,
"invalid header: largest frame size greater than file size\n");
return AVERROR(EIO);
}
avio_skip(pb, 4);
vst->codecpar->width = avio_rl32(pb);
vst->codecpar->height = avio_rl32(pb);
fps_num = avio_rl32(pb);
fps_den = avio_rl32(pb);
if (fps_num == 0 || fps_den == 0) {
av_log(s, AV_LOG_ERROR,
"invalid header: invalid fps (%"PRIu32"/%"PRIu32")\n",
fps_num, fps_den);
return AVERROR(EIO);
}
avpriv_set_pts_info(vst, 64, fps_den, fps_num);
vst->avg_frame_rate = av_inv_q(vst->time_base);
vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codecpar->codec_id = AV_CODEC_ID_BINKVIDEO;
vst->codecpar->extradata = av_mallocz(4 + AV_INPUT_BUFFER_PADDING_SIZE);
if (!vst->codecpar->extradata)
return AVERROR(ENOMEM);
vst->codecpar->extradata_size = 4;
avio_read(pb, vst->codecpar->extradata, 4);
bink->num_audio_tracks = avio_rl32(pb);
if (bink->num_audio_tracks > BINK_MAX_AUDIO_TRACKS) {
av_log(s, AV_LOG_ERROR,
"invalid header: more than "AV_STRINGIFY(BINK_MAX_AUDIO_TRACKS)" audio tracks (%"PRIu32")\n",
bink->num_audio_tracks);
return AVERROR(EIO);
}
if (bink->num_audio_tracks) {
avio_skip(pb, 4 * bink->num_audio_tracks);
for (i = 0; i < bink->num_audio_tracks; i++) {
ast = avformat_new_stream(s, NULL);
if (!ast)
return AVERROR(ENOMEM);
ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codecpar->codec_tag = 0;
ast->codecpar->sample_rate = avio_rl16(pb);
avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
flags = avio_rl16(pb);
ast->codecpar->codec_id = flags & BINK_AUD_USEDCT ?
AV_CODEC_ID_BINKAUDIO_DCT : AV_CODEC_ID_BINKAUDIO_RDFT;
if (flags & BINK_AUD_STEREO) {
ast->codecpar->channels = 2;
ast->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
} else {
ast->codecpar->channels = 1;
ast->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
}
ast->codecpar->extradata = av_mallocz(4 + AV_INPUT_BUFFER_PADDING_SIZE);
if (!ast->codecpar->extradata)
return AVERROR(ENOMEM);
ast->codecpar->extradata_size = 4;
AV_WL32(ast->codecpar->extradata, vst->codecpar->codec_tag);
}
for (i = 0; i < bink->num_audio_tracks; i++)
s->streams[i + 1]->id = avio_rl32(pb);
}
/* frame index table */
next_pos = avio_rl32(pb);
for (i = 0; i < vst->duration; i++) {
pos = next_pos;
if (i == vst->duration - 1) {
next_pos = bink->file_size;
keyframe = 0;
} else {
next_pos = avio_rl32(pb);
keyframe = pos & 1;
}
pos &= ~1;
next_pos &= ~1;
if (next_pos <= pos) {
av_log(s, AV_LOG_ERROR, "invalid frame index table\n");
return AVERROR(EIO);
}
av_add_index_entry(vst, pos, i, next_pos - pos, 0,
keyframe ? AVINDEX_KEYFRAME : 0);
}
avio_skip(pb, 4);
bink->current_track = -1;
return 0;
}
static int read_packet(AVFormatContext *s, AVPacket *pkt)
{
BinkDemuxContext *bink = s->priv_data;
AVIOContext *pb = s->pb;
int ret;
if (bink->current_track < 0) {
int index_entry;
AVStream *st = s->streams[0]; // stream 0 is video stream with index
if (bink->video_pts >= st->duration)
return AVERROR(EIO);
index_entry = av_index_search_timestamp(st, bink->video_pts,
AVSEEK_FLAG_ANY);
if (index_entry < 0) {
av_log(s, AV_LOG_ERROR,
"could not find index entry for frame %"PRId64"\n",
bink->video_pts);
return AVERROR(EIO);
}
bink->remain_packet_size = st->index_entries[index_entry].size;
bink->current_track = 0;
}
while (bink->current_track < bink->num_audio_tracks) {
uint32_t audio_size = avio_rl32(pb);
if (audio_size > bink->remain_packet_size - 4) {
av_log(s, AV_LOG_ERROR,
"frame %"PRId64": audio size in header (%"PRIu32") > size of packet left (%"PRIu32")\n",
bink->video_pts, audio_size, bink->remain_packet_size);
return AVERROR(EIO);
}
bink->remain_packet_size -= 4 + audio_size;
bink->current_track++;
if (audio_size >= 4) {
/* get one audio packet per track */
if ((ret = av_get_packet(pb, pkt, audio_size)) < 0)
return ret;
pkt->stream_index = bink->current_track;
pkt->pts = bink->audio_pts[bink->current_track - 1];
/* Each audio packet reports the number of decompressed samples
(in bytes). We use this value to calcuate the audio PTS */
if (pkt->size >= 4)
bink->audio_pts[bink->current_track -1] +=
AV_RL32(pkt->data) / (2 * s->streams[bink->current_track]->codecpar->channels);
return 0;
} else {
avio_skip(pb, audio_size);
}
}
/* get video packet */
if ((ret = av_get_packet(pb, pkt, bink->remain_packet_size)) < 0)
return ret;
pkt->stream_index = 0;
pkt->pts = bink->video_pts++;
pkt->flags |= AV_PKT_FLAG_KEY;
/* -1 instructs the next call to read_packet() to read the next frame */
bink->current_track = -1;
return 0;
}
static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
BinkDemuxContext *bink = s->priv_data;
AVStream *vst = s->streams[0];
if (!s->pb->seekable)
return -1;
/* seek to the first frame */
if (avio_seek(s->pb, vst->index_entries[0].pos, SEEK_SET) < 0)
return -1;
bink->video_pts = 0;
memset(bink->audio_pts, 0, sizeof(bink->audio_pts));
bink->current_track = -1;
return 0;
}
AVInputFormat ff_bink_demuxer = {
.name = "bink",
.long_name = NULL_IF_CONFIG_SMALL("Bink"),
.priv_data_size = sizeof(BinkDemuxContext),
.read_probe = probe,
.read_header = read_header,
.read_packet = read_packet,
.read_seek = read_seek,
};