RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
ffmpeg/libavformat/avidec.c

1607 lines
54 KiB
C
Raw Blame History

/*
* AVI demuxer
* Copyright (c) 2001 Fabrice Bellard
*
* 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
*/
#include <inttypes.h>
#include "libavutil/avstring.h"
#include "libavutil/bswap.h"
#include "libavutil/dict.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "avformat.h"
#include "avi.h"
#include "dv.h"
#include "internal.h"
#include "riff.h"
#undef NDEBUG
#include <assert.h>
typedef struct AVIStream {
int64_t frame_offset; /* current frame (video) or byte (audio) counter
* (used to compute the pts) */
int remaining;
int packet_size;
uint32_t handler;
uint32_t scale;
uint32_t rate;
int sample_size; /* size of one sample (or packet)
* (in the rate/scale sense) in bytes */
int64_t cum_len; /* temporary storage (used during seek) */
int prefix; /* normally 'd'<<8 + 'c' or 'w'<<8 + 'b' */
int prefix_count;
uint32_t pal[256];
int has_pal;
int dshow_block_align; /* block align variable used to emulate bugs in
* the MS dshow demuxer */
AVFormatContext *sub_ctx;
AVPacket sub_pkt;
uint8_t *sub_buffer;
} AVIStream;
typedef struct AVIContext {
int64_t riff_end;
int64_t movi_end;
int64_t fsize;
int64_t movi_list;
int64_t last_pkt_pos;
int index_loaded;
int is_odml;
int non_interleaved;
int stream_index;
DVDemuxContext *dv_demux;
int odml_depth;
#define MAX_ODML_DEPTH 1000
} AVIContext;
static const char avi_headers[][8] = {
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19 },
{ 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
{ 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
{ 0 }
};
static const AVMetadataConv avi_metadata_conv[] = {
{ "strn", "title" },
{ 0 },
};
static int avi_load_index(AVFormatContext *s);
static int guess_ni_flag(AVFormatContext *s);
#define print_tag(str, tag, size) \
av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n", \
str, tag & 0xff, \
(tag >> 8) & 0xff, \
(tag >> 16) & 0xff, \
(tag >> 24) & 0xff, \
size)
static inline int get_duration(AVIStream *ast, int len)
{
if (ast->sample_size)
return len;
else if (ast->dshow_block_align)
return (len + ast->dshow_block_align - 1) / ast->dshow_block_align;
else
return 1;
}
static int get_riff(AVFormatContext *s, AVIOContext *pb)
{
AVIContext *avi = s->priv_data;
char header[8];
int i;
/* check RIFF header */
avio_read(pb, header, 4);
avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
avi->riff_end += avio_tell(pb); /* RIFF chunk end */
avio_read(pb, header + 4, 4);
for (i = 0; avi_headers[i][0]; i++)
if (!memcmp(header, avi_headers[i], 8))
break;
if (!avi_headers[i][0])
return AVERROR_INVALIDDATA;
if (header[7] == 0x19)
av_log(s, AV_LOG_INFO,
"This file has been generated by a totally broken muxer.\n");
return 0;
}
static int read_braindead_odml_indx(AVFormatContext *s, int frame_num)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int longs_pre_entry = avio_rl16(pb);
int index_sub_type = avio_r8(pb);
int index_type = avio_r8(pb);
int entries_in_use = avio_rl32(pb);
int chunk_id = avio_rl32(pb);
int64_t base = avio_rl64(pb);
int stream_id = ((chunk_id & 0xFF) - '0') * 10 +
((chunk_id >> 8 & 0xFF) - '0');
AVStream *st;
AVIStream *ast;
int i;
int64_t last_pos = -1;
int64_t filesize = avi->fsize;
av_dlog(s,
"longs_pre_entry:%d index_type:%d entries_in_use:%d "
"chunk_id:%X base:%16"PRIX64"\n",
longs_pre_entry,
index_type,
entries_in_use,
chunk_id,
base);
if (stream_id >= s->nb_streams || stream_id < 0)
return AVERROR_INVALIDDATA;
st = s->streams[stream_id];
ast = st->priv_data;
if (index_sub_type)
return AVERROR_INVALIDDATA;
avio_rl32(pb);
if (index_type && longs_pre_entry != 2)
return AVERROR_INVALIDDATA;
if (index_type > 1)
return AVERROR_INVALIDDATA;
if (filesize > 0 && base >= filesize) {
av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
if (base >> 32 == (base & 0xFFFFFFFF) &&
(base & 0xFFFFFFFF) < filesize &&
filesize <= 0xFFFFFFFF)
base &= 0xFFFFFFFF;
else
return AVERROR_INVALIDDATA;
}
for (i = 0; i < entries_in_use; i++) {
if (index_type) {
int64_t pos = avio_rl32(pb) + base - 8;
int len = avio_rl32(pb);
int key = len >= 0;
len &= 0x7FFFFFFF;
av_dlog(s, "pos:%"PRId64", len:%X\n", pos, len);
if (pb->eof_reached)
return AVERROR_INVALIDDATA;
if (last_pos == pos || pos == base - 8)
avi->non_interleaved = 1;
if (last_pos != pos && (len || !ast->sample_size))
av_add_index_entry(st, pos, ast->cum_len, len, 0,
key ? AVINDEX_KEYFRAME : 0);
ast->cum_len += get_duration(ast, len);
last_pos = pos;
} else {
int64_t offset, pos;
int duration;
offset = avio_rl64(pb);
avio_rl32(pb); /* size */
duration = avio_rl32(pb);
if (pb->eof_reached)
return AVERROR_INVALIDDATA;
pos = avio_tell(pb);
if (avi->odml_depth > MAX_ODML_DEPTH) {
av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
return AVERROR_INVALIDDATA;
}
avio_seek(pb, offset + 8, SEEK_SET);
avi->odml_depth++;
read_braindead_odml_indx(s, frame_num);
avi->odml_depth--;
frame_num += duration;
avio_seek(pb, pos, SEEK_SET);
}
}
avi->index_loaded = 1;
return 0;
}
static void clean_index(AVFormatContext *s)
{
int i;
int64_t j;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int n = st->nb_index_entries;
int max = ast->sample_size;
int64_t pos, size, ts;
if (n != 1 || ast->sample_size == 0)
continue;
while (max < 1024)
max += max;
pos = st->index_entries[0].pos;
size = st->index_entries[0].size;
ts = st->index_entries[0].timestamp;
for (j = 0; j < size; j += max)
av_add_index_entry(st, pos + j, ts + j, FFMIN(max, size - j), 0,
AVINDEX_KEYFRAME);
}
}
static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag,
uint32_t size)
{
AVIOContext *pb = s->pb;
char key[5] = { 0 };
char *value;
size += (size & 1);
if (size == UINT_MAX)
return AVERROR(EINVAL);
value = av_malloc(size + 1);
if (!value)
return AVERROR(ENOMEM);
avio_read(pb, value, size);
value[size] = 0;
AV_WL32(key, tag);
return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
AV_DICT_DONT_STRDUP_VAL);
}
static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
{
char month[4], time[9], buffer[64];
int i, day, year;
/* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
month, &day, time, &year) == 4) {
for (i = 0; i < 12; i++)
if (!av_strcasecmp(month, months[i])) {
snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
year, i + 1, day, time);
av_dict_set(metadata, "creation_time", buffer, 0);
}
} else if (date[4] == '/' && date[7] == '/') {
date[4] = date[7] = '-';
av_dict_set(metadata, "creation_time", date, 0);
}
}
static void avi_read_nikon(AVFormatContext *s, uint64_t end)
{
while (avio_tell(s->pb) < end) {
uint32_t tag = avio_rl32(s->pb);
uint32_t size = avio_rl32(s->pb);
switch (tag) {
case MKTAG('n', 'c', 't', 'g'): /* Nikon Tags */
{
uint64_t tag_end = avio_tell(s->pb) + size;
while (avio_tell(s->pb) < tag_end) {
uint16_t tag = avio_rl16(s->pb);
uint16_t size = avio_rl16(s->pb);
const char *name = NULL;
char buffer[64] = { 0 };
size -= avio_read(s->pb, buffer,
FFMIN(size, sizeof(buffer) - 1));
switch (tag) {
case 0x03:
name = "maker";
break;
case 0x04:
name = "model";
break;
case 0x13:
name = "creation_time";
if (buffer[4] == ':' && buffer[7] == ':')
buffer[4] = buffer[7] = '-';
break;
}
if (name)
av_dict_set(&s->metadata, name, buffer, 0);
avio_skip(s->pb, size);
}
break;
}
default:
avio_skip(s->pb, size);
break;
}
}
}
static int avi_read_header(AVFormatContext *s)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
unsigned int tag, tag1, handler;
int codec_type, stream_index, frame_period;
unsigned int size;
int i;
AVStream *st;
AVIStream *ast = NULL;
int avih_width = 0, avih_height = 0;
int amv_file_format = 0;
uint64_t list_end = 0;
int ret;
avi->stream_index = -1;
ret = get_riff(s, pb);
if (ret < 0)
return ret;
avi->fsize = avio_size(pb);
if (avi->fsize <= 0 || avi->fsize < avi->riff_end)
avi->fsize = avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
/* first list tag */
stream_index = -1;
codec_type = -1;
frame_period = 0;
for (;;) {
if (pb->eof_reached)
goto fail;
tag = avio_rl32(pb);
size = avio_rl32(pb);
print_tag("tag", tag, size);
switch (tag) {
case MKTAG('L', 'I', 'S', 'T'):
list_end = avio_tell(pb) + size;
/* Ignored, except at start of video packets. */
tag1 = avio_rl32(pb);
print_tag("list", tag1, 0);
if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
avi->movi_list = avio_tell(pb) - 4;
if (size)
avi->movi_end = avi->movi_list + size + (size & 1);
else
avi->movi_end = avi->fsize;
av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
goto end_of_header;
} else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
ff_read_riff_info(s, size - 4);
else if (tag1 == MKTAG('n', 'c', 'd', 't'))
avi_read_nikon(s, list_end);
break;
case MKTAG('I', 'D', 'I', 'T'):
{
unsigned char date[64] = { 0 };
size += (size & 1);
size -= avio_read(pb, date, FFMIN(size, sizeof(date) - 1));
avio_skip(pb, size);
avi_metadata_creation_time(&s->metadata, date);
break;
}
case MKTAG('d', 'm', 'l', 'h'):
avi->is_odml = 1;
avio_skip(pb, size + (size & 1));
break;
case MKTAG('a', 'm', 'v', 'h'):
amv_file_format = 1;
case MKTAG('a', 'v', 'i', 'h'):
/* AVI header */
/* using frame_period is bad idea */
frame_period = avio_rl32(pb);
avio_skip(pb, 4);
avio_rl32(pb);
avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;
avio_skip(pb, 2 * 4);
avio_rl32(pb);
avio_rl32(pb);
avih_width = avio_rl32(pb);
avih_height = avio_rl32(pb);
avio_skip(pb, size - 10 * 4);
break;
case MKTAG('s', 't', 'r', 'h'):
/* stream header */
tag1 = avio_rl32(pb);
handler = avio_rl32(pb); /* codec tag */
if (tag1 == MKTAG('p', 'a', 'd', 's')) {
avio_skip(pb, size - 8);
break;
} else {
stream_index++;
st = avformat_new_stream(s, NULL);
if (!st)
goto fail;
st->id = stream_index;
ast = av_mallocz(sizeof(AVIStream));
if (!ast)
goto fail;
st->priv_data = ast;
}
if (amv_file_format)
tag1 = stream_index ? MKTAG('a', 'u', 'd', 's')
: MKTAG('v', 'i', 'd', 's');
print_tag("strh", tag1, -1);
if (tag1 == MKTAG('i', 'a', 'v', 's') ||
tag1 == MKTAG('i', 'v', 'a', 's')) {
int64_t dv_dur;
/* After some consideration -- I don't think we
* have to support anything but DV in type1 AVIs. */
if (s->nb_streams != 1)
goto fail;
if (handler != MKTAG('d', 'v', 's', 'd') &&
handler != MKTAG('d', 'v', 'h', 'd') &&
handler != MKTAG('d', 'v', 's', 'l'))
goto fail;
ast = s->streams[0]->priv_data;
av_freep(&s->streams[0]->codec->extradata);
av_freep(&s->streams[0]->codec);
av_freep(&s->streams[0]->info);
av_freep(&s->streams[0]);
s->nb_streams = 0;
if (CONFIG_DV_DEMUXER) {
avi->dv_demux = avpriv_dv_init_demux(s);
if (!avi->dv_demux)
goto fail;
} else
goto fail;
s->streams[0]->priv_data = ast;
avio_skip(pb, 3 * 4);
ast->scale = avio_rl32(pb);
ast->rate = avio_rl32(pb);
avio_skip(pb, 4); /* start time */
dv_dur = avio_rl32(pb);
if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
dv_dur *= AV_TIME_BASE;
s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
}
/* else, leave duration alone; timing estimation in utils.c
* will make a guess based on bitrate. */
stream_index = s->nb_streams - 1;
avio_skip(pb, size - 9 * 4);
break;
}
assert(stream_index < s->nb_streams);
ast->handler = handler;
avio_rl32(pb); /* flags */
avio_rl16(pb); /* priority */
avio_rl16(pb); /* language */
avio_rl32(pb); /* initial frame */
ast->scale = avio_rl32(pb);
ast->rate = avio_rl32(pb);
if (!(ast->scale && ast->rate)) {
av_log(s, AV_LOG_WARNING,
"scale/rate is %"PRIu32"/%"PRIu32" which is invalid. "
"(This file has been generated by broken software.)\n",
ast->scale,
ast->rate);
if (frame_period) {
ast->rate = 1000000;
ast->scale = frame_period;
} else {
ast->rate = 25;
ast->scale = 1;
}
}
avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
ast->cum_len = avio_rl32(pb); /* start */
st->nb_frames = avio_rl32(pb);
st->start_time = 0;
avio_rl32(pb); /* buffer size */
avio_rl32(pb); /* quality */
ast->sample_size = avio_rl32(pb); /* sample ssize */
ast->cum_len *= FFMAX(1, ast->sample_size);
av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",
ast->rate, ast->scale, ast->sample_size);
switch (tag1) {
case MKTAG('v', 'i', 'd', 's'):
codec_type = AVMEDIA_TYPE_VIDEO;
ast->sample_size = 0;
break;
case MKTAG('a', 'u', 'd', 's'):
codec_type = AVMEDIA_TYPE_AUDIO;
break;
case MKTAG('t', 'x', 't', 's'):
codec_type = AVMEDIA_TYPE_SUBTITLE;
break;
case MKTAG('d', 'a', 't', 's'):
codec_type = AVMEDIA_TYPE_DATA;
break;
default:
av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
goto fail;
}
if (ast->sample_size == 0)
st->duration = st->nb_frames;
ast->frame_offset = ast->cum_len;
avio_skip(pb, size - 12 * 4);
break;
case MKTAG('s', 't', 'r', 'f'):
/* stream header */
if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
avio_skip(pb, size);
} else {
uint64_t cur_pos = avio_tell(pb);
if (cur_pos < list_end)
size = FFMIN(size, list_end - cur_pos);
st = s->streams[stream_index];
switch (codec_type) {
case AVMEDIA_TYPE_VIDEO:
if (amv_file_format) {
st->codec->width = avih_width;
st->codec->height = avih_height;
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = AV_CODEC_ID_AMV;
avio_skip(pb, size);
break;
}
tag1 = ff_get_bmp_header(pb, st);
if (tag1 == MKTAG('D', 'X', 'S', 'B') ||
tag1 == MKTAG('D', 'X', 'S', 'A')) {
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codec->codec_tag = tag1;
st->codec->codec_id = AV_CODEC_ID_XSUB;
break;
}
if (size > 10 * 4 && size < (1 << 30)) {
st->codec->extradata_size = size - 10 * 4;
st->codec->extradata = av_malloc(st->codec->extradata_size +
FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata) {
st->codec->extradata_size = 0;
return AVERROR(ENOMEM);
}
avio_read(pb,
st->codec->extradata,
st->codec->extradata_size);
}
// FIXME: check if the encoder really did this correctly
if (st->codec->extradata_size & 1)
avio_r8(pb);
/* Extract palette from extradata if bpp <= 8.
* This code assumes that extradata contains only palette.
* This is true for all paletted codecs implemented in
* Libav. */
if (st->codec->extradata_size &&
(st->codec->bits_per_coded_sample <= 8)) {
int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
const uint8_t *pal_src;
pal_size = FFMIN(pal_size, st->codec->extradata_size);
pal_src = st->codec->extradata +
st->codec->extradata_size - pal_size;
#if HAVE_BIGENDIAN
for (i = 0; i < pal_size / 4; i++)
ast->pal[i] = av_bswap32(((uint32_t *)pal_src)[i]);
#else
memcpy(ast->pal, pal_src, pal_size);
#endif
ast->has_pal = 1;
}
print_tag("video", tag1, 0);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_tag = tag1;
st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags,
tag1);
/* This is needed to get the pict type which is necessary
* for generating correct pts. */
st->need_parsing = AVSTREAM_PARSE_HEADERS;
if (st->codec->codec_id == AV_CODEC_ID_MPEG4 &&
ast->handler == MKTAG('X', 'V', 'I', 'D'))
st->codec->codec_tag = MKTAG('X', 'V', 'I', 'D');
// Support "Resolution 1:1" for Avid AVI Codec
if (tag1 == MKTAG('A', 'V', 'R', 'n') &&
st->codec->extradata_size >= 31 &&
!memcmp(&st->codec->extradata[28], "1:1", 3))
st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
if (st->codec->codec_tag == 0 && st->codec->height > 0 &&
st->codec->extradata_size < 1U << 30) {
st->codec->extradata_size += 9;
if ((ret = av_reallocp(&st->codec->extradata,
st->codec->extradata_size +
FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {
st->codec->extradata_size = 0;
return ret;
} else
memcpy(st->codec->extradata + st->codec->extradata_size - 9,
"BottomUp", 9);
}
st->codec->height = FFABS(st->codec->height);
// avio_skip(pb, size - 5 * 4);
break;
case AVMEDIA_TYPE_AUDIO:
ret = ff_get_wav_header(pb, st->codec, size);
if (ret < 0)
return ret;
ast->dshow_block_align = st->codec->block_align;
if (ast->sample_size && st->codec->block_align &&
ast->sample_size != st->codec->block_align) {
av_log(s,
AV_LOG_WARNING,
"sample size (%d) != block align (%d)\n",
ast->sample_size,
st->codec->block_align);
ast->sample_size = st->codec->block_align;
}
/* 2-aligned
* (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
if (size & 1)
avio_skip(pb, 1);
/* Force parsing as several audio frames can be in
* one packet and timestamps refer to packet start. */
st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;
/* ADTS header is in extradata, AAC without header must be
* stored as exact frames. Parser not needed and it will
* fail. */
if (st->codec->codec_id == AV_CODEC_ID_AAC &&
st->codec->extradata_size)
st->need_parsing = AVSTREAM_PARSE_NONE;
/* AVI files with Xan DPCM audio (wrongly) declare PCM
* audio in the header but have Axan as stream_code_tag. */
if (ast->handler == AV_RL32("Axan")) {
st->codec->codec_id = AV_CODEC_ID_XAN_DPCM;
st->codec->codec_tag = 0;
}
if (amv_file_format) {
st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_AMV;
ast->dshow_block_align = 0;
}
break;
case AVMEDIA_TYPE_SUBTITLE:
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codec->codec_id = AV_CODEC_ID_PROBE;
break;
default:
st->codec->codec_type = AVMEDIA_TYPE_DATA;
st->codec->codec_id = AV_CODEC_ID_NONE;
st->codec->codec_tag = 0;
avio_skip(pb, size);
break;
}
}
break;
case MKTAG('i', 'n', 'd', 'x'):
i = avio_tell(pb);
if (pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) &&
read_braindead_odml_indx(s, 0) < 0 &&
(s->error_recognition & AV_EF_EXPLODE))
goto fail;
avio_seek(pb, i + size, SEEK_SET);
break;
case MKTAG('v', 'p', 'r', 'p'):
if (stream_index < (unsigned)s->nb_streams && size > 9 * 4) {
AVRational active, active_aspect;
st = s->streams[stream_index];
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
active_aspect.den = avio_rl16(pb);
active_aspect.num = avio_rl16(pb);
active.num = avio_rl32(pb);
active.den = avio_rl32(pb);
avio_rl32(pb); // nbFieldsPerFrame
if (active_aspect.num && active_aspect.den &&
active.num && active.den) {
st->sample_aspect_ratio = av_div_q(active_aspect, active);
av_dlog(s, "vprp %d/%d %d/%d\n",
active_aspect.num, active_aspect.den,
active.num, active.den);
}
size -= 9 * 4;
}
avio_skip(pb, size);
break;
case MKTAG('s', 't', 'r', 'n'):
if (s->nb_streams) {
ret = avi_read_tag(s, s->streams[s->nb_streams - 1], tag, size);
if (ret < 0)
return ret;
break;
}
default:
if (size > 1000000) {
av_log(s, AV_LOG_ERROR,
"Something went wrong during header parsing, "
"I will ignore it and try to continue anyway.\n");
if (s->error_recognition & AV_EF_EXPLODE)
goto fail;
avi->movi_list = avio_tell(pb) - 4;
avi->movi_end = avi->fsize;
goto end_of_header;
}
/* skip tag */
size += (size & 1);
avio_skip(pb, size);
break;
}
}
end_of_header:
/* check stream number */
if (stream_index != s->nb_streams - 1) {
fail:
return AVERROR_INVALIDDATA;
}
if (!avi->index_loaded && pb->seekable)
avi_load_index(s);
avi->index_loaded = 1;
if ((ret = guess_ni_flag(s)) < 0)
return ret;
avi->non_interleaved |= ret;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
if (st->nb_index_entries)
break;
}
if (i == s->nb_streams && avi->non_interleaved) {
av_log(s, AV_LOG_WARNING,
"Non-interleaved AVI without index, switching to interleaved\n");
avi->non_interleaved = 0;
}
if (avi->non_interleaved) {
av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
clean_index(s);
}
ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);
return 0;
}
static int read_gab2_sub(AVStream *st, AVPacket *pkt)
{
if (pkt->size >= 7 &&
!strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data + 5) == 2) {
uint8_t desc[256];
int score = AVPROBE_SCORE_EXTENSION, ret;
AVIStream *ast = st->priv_data;
AVInputFormat *sub_demuxer;
AVRational time_base;
AVIOContext *pb = avio_alloc_context(pkt->data + 7,
pkt->size - 7,
0, NULL, NULL, NULL, NULL);
AVProbeData pd;
unsigned int desc_len = avio_rl32(pb);
if (desc_len > pb->buf_end - pb->buf_ptr)
goto error;
ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
avio_skip(pb, desc_len - ret);
if (*desc)
av_dict_set(&st->metadata, "title", desc, 0);
avio_rl16(pb); /* flags? */
avio_rl32(pb); /* data size */
pd = (AVProbeData) { .buf = pb->buf_ptr,
.buf_size = pb->buf_end - pb->buf_ptr };
if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
goto error;
if (!(ast->sub_ctx = avformat_alloc_context()))
goto error;
ast->sub_ctx->pb = pb;
if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
ff_read_packet(ast->sub_ctx, &ast->sub_pkt);
*st->codec = *ast->sub_ctx->streams[0]->codec;
ast->sub_ctx->streams[0]->codec->extradata = NULL;
time_base = ast->sub_ctx->streams[0]->time_base;
avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
}
ast->sub_buffer = pkt->data;
memset(pkt, 0, sizeof(*pkt));
return 1;
error:
av_freep(&pb);
}
return 0;
}
static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,
AVPacket *pkt)
{
AVIStream *ast, *next_ast = next_st->priv_data;
int64_t ts, next_ts, ts_min = INT64_MAX;
AVStream *st, *sub_st = NULL;
int i;
next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
AV_TIME_BASE_Q);
for (i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
ast = st->priv_data;
if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);
if (ts <= next_ts && ts < ts_min) {
ts_min = ts;
sub_st = st;
}
}
}
if (sub_st) {
ast = sub_st->priv_data;
*pkt = ast->sub_pkt;
pkt->stream_index = sub_st->index;
if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
ast->sub_pkt.data = NULL;
}
return sub_st;
}
static int get_stream_idx(int *d)
{
if (d[0] >= '0' && d[0] <= '9' &&
d[1] >= '0' && d[1] <= '9') {
return (d[0] - '0') * 10 + (d[1] - '0');
} else {
return 100; // invalid stream ID
}
}
static int avi_sync(AVFormatContext *s, int exit_early)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int n;
unsigned int d[8];
unsigned int size;
int64_t i, sync;
start_sync:
memset(d, -1, sizeof(d));
for (i = sync = avio_tell(pb); !pb->eof_reached; i++) {
int j;
for (j = 0; j < 7; j++)
d[j] = d[j + 1];
d[7] = avio_r8(pb);
size = d[4] + (d[5] << 8) + (d[6] << 16) + (d[7] << 24);
n = get_stream_idx(d + 2);
av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",
d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
if (i + (uint64_t)size > avi->fsize || d[0] > 127)
continue;
// parse ix##
if ((d[0] == 'i' && d[1] == 'x' && n < s->nb_streams) ||
// parse JUNK
(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K') ||
(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')) {
avio_skip(pb, size);
goto start_sync;
}
// parse stray LIST
if (d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T') {
avio_skip(pb, 4);
goto start_sync;
}
n = avi->dv_demux ? 0 : get_stream_idx(d);
if (!((i - avi->last_pkt_pos) & 1) &&
get_stream_idx(d + 1) < s->nb_streams)
continue;
// detect ##ix chunk and skip
if (d[2] == 'i' && d[3] == 'x' && n < s->nb_streams) {
avio_skip(pb, size);
goto start_sync;
}
// parse ##dc/##wb
if (n < s->nb_streams) {
AVStream *st;
AVIStream *ast;
st = s->streams[n];
ast = st->priv_data;
if (s->nb_streams >= 2) {
AVStream *st1 = s->streams[1];
AVIStream *ast1 = st1->priv_data;
// workaround for broken small-file-bug402.avi
if (d[2] == 'w' && d[3] == 'b' && n == 0 &&
st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
st1->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
ast->prefix == 'd' * 256 + 'c' &&
(d[2] * 256 + d[3] == ast1->prefix ||
!ast1->prefix_count)) {
n = 1;
st = st1;
ast = ast1;
av_log(s, AV_LOG_WARNING,
"Invalid stream + prefix combination, assuming audio.\n");
}
}
if (!avi->dv_demux &&
((st->discard >= AVDISCARD_DEFAULT && size == 0) /* ||
// FIXME: needs a little reordering
(st->discard >= AVDISCARD_NONKEY &&
!(pkt->flags & AV_PKT_FLAG_KEY)) */
|| st->discard >= AVDISCARD_ALL)) {
if (!exit_early) {
ast->frame_offset += get_duration(ast, size);
}
avio_skip(pb, size);
goto start_sync;
}
if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {
int k = avio_r8(pb);
int last = (k + avio_r8(pb) - 1) & 0xFF;
avio_rl16(pb); // flags
// b + (g << 8) + (r << 16);
for (; k <= last; k++)
ast->pal[k] = avio_rb32(pb) >> 8;
ast->has_pal = 1;
goto start_sync;
} else if (((ast->prefix_count < 5 || sync + 9 > i) &&
d[2] < 128 && d[3] < 128) ||
d[2] * 256 + d[3] == ast->prefix /* ||
(d[2] == 'd' && d[3] == 'c') ||
(d[2] == 'w' && d[3] == 'b') */) {
if (exit_early)
return 0;
if (d[2] * 256 + d[3] == ast->prefix)
ast->prefix_count++;
else {
ast->prefix = d[2] * 256 + d[3];
ast->prefix_count = 0;
}
avi->stream_index = n;
ast->packet_size = size + 8;
ast->remaining = size;
if (size || !ast->sample_size) {
uint64_t pos = avio_tell(pb) - 8;
if (!st->index_entries || !st->nb_index_entries ||
st->index_entries[st->nb_index_entries - 1].pos < pos) {
av_add_index_entry(st, pos, ast->frame_offset, size,
0, AVINDEX_KEYFRAME);
}
}
return 0;
}
}
}
return AVERROR_EOF;
}
static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int err;
#if FF_API_DESTRUCT_PACKET
void *dstr;
#endif
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
if (size >= 0)
return size;
else
goto resync;
}
if (avi->non_interleaved) {
int best_stream_index = 0;
AVStream *best_st = NULL;
AVIStream *best_ast;
int64_t best_ts = INT64_MAX;
int i;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int64_t ts = ast->frame_offset;
int64_t last_ts;
if (!st->nb_index_entries)
continue;
last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
if (!ast->remaining && ts > last_ts)
continue;
ts = av_rescale_q(ts, st->time_base,
(AVRational) { FFMAX(1, ast->sample_size),
AV_TIME_BASE });
av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,
st->time_base.num, st->time_base.den, ast->frame_offset);
if (ts < best_ts) {
best_ts = ts;
best_st = st;
best_stream_index = i;
}
}
if (!best_st)
return AVERROR_EOF;
best_ast = best_st->priv_data;
best_ts = av_rescale_q(best_ts,
(AVRational) { FFMAX(1, best_ast->sample_size),
AV_TIME_BASE },
best_st->time_base);
if (best_ast->remaining) {
i = av_index_search_timestamp(best_st,
best_ts,
AVSEEK_FLAG_ANY |
AVSEEK_FLAG_BACKWARD);
} else {
i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
if (i >= 0)
best_ast->frame_offset = best_st->index_entries[i].timestamp;
}
if (i >= 0) {
int64_t pos = best_st->index_entries[i].pos;
pos += best_ast->packet_size - best_ast->remaining;
avio_seek(s->pb, pos + 8, SEEK_SET);
assert(best_ast->remaining <= best_ast->packet_size);
avi->stream_index = best_stream_index;
if (!best_ast->remaining)
best_ast->packet_size =
best_ast->remaining = best_st->index_entries[i].size;
}
}
resync:
if (avi->stream_index >= 0) {
AVStream *st = s->streams[avi->stream_index];
AVIStream *ast = st->priv_data;
int size, err;
if (get_subtitle_pkt(s, st, pkt))
return 0;
// minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
if (ast->sample_size <= 1)
size = INT_MAX;
else if (ast->sample_size < 32)
// arbitrary multiplier to avoid tiny packets for raw PCM data
size = 1024 * ast->sample_size;
else
size = ast->sample_size;
if (size > ast->remaining)
size = ast->remaining;
avi->last_pkt_pos = avio_tell(pb);
err = av_get_packet(pb, pkt, size);
if (err < 0)
return err;
if (ast->has_pal && pkt->data && pkt->size < (unsigned)INT_MAX / 2) {
uint8_t *pal;
pal = av_packet_new_side_data(pkt,
AV_PKT_DATA_PALETTE,
AVPALETTE_SIZE);
if (!pal) {
av_log(s, AV_LOG_ERROR,
"Failed to allocate data for palette\n");
} else {
memcpy(pal, ast->pal, AVPALETTE_SIZE);
ast->has_pal = 0;
}
}
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
AVBufferRef *avbuf = pkt->buf;
#if FF_API_DESTRUCT_PACKET
FF_DISABLE_DEPRECATION_WARNINGS
dstr = pkt->destruct;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
pkt->data, pkt->size);
#if FF_API_DESTRUCT_PACKET
FF_DISABLE_DEPRECATION_WARNINGS
pkt->destruct = dstr;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
pkt->buf = avbuf;
pkt->flags |= AV_PKT_FLAG_KEY;
if (size < 0)
av_free_packet(pkt);
} else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&
!st->codec->codec_tag && read_gab2_sub(st, pkt)) {
ast->frame_offset++;
avi->stream_index = -1;
ast->remaining = 0;
goto resync;
} else {
/* XXX: How to handle B-frames in AVI? */
pkt->dts = ast->frame_offset;
// pkt->dts += ast->start;
if (ast->sample_size)
pkt->dts /= ast->sample_size;
av_dlog(s,
"dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "
"base:%d st:%d size:%d\n",
pkt->dts,
ast->frame_offset,
ast->scale,
ast->rate,
ast->sample_size,
AV_TIME_BASE,
avi->stream_index,
size);
pkt->stream_index = avi->stream_index;
if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
AVIndexEntry *e;
int index;
assert(st->index_entries);
index = av_index_search_timestamp(st, ast->frame_offset, 0);
e = &st->index_entries[index];
if (index >= 0 && e->timestamp == ast->frame_offset)
if (e->flags & AVINDEX_KEYFRAME)
pkt->flags |= AV_PKT_FLAG_KEY;
} else {
pkt->flags |= AV_PKT_FLAG_KEY;
}
ast->frame_offset += get_duration(ast, pkt->size);
}
ast->remaining -= err;
if (!ast->remaining) {
avi->stream_index = -1;
ast->packet_size = 0;
}
return 0;
}
if ((err = avi_sync(s, 0)) < 0)
return err;
goto resync;
}
/* XXX: We make the implicit supposition that the positions are sorted
* for each stream. */
static int avi_read_idx1(AVFormatContext *s, int size)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int nb_index_entries, i;
AVStream *st;
AVIStream *ast;
unsigned int index, tag, flags, pos, len, first_packet = 1;
unsigned last_pos = -1;
int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
nb_index_entries = size / 16;
if (nb_index_entries <= 0)
return AVERROR_INVALIDDATA;
idx1_pos = avio_tell(pb);
avio_seek(pb, avi->movi_list + 4, SEEK_SET);
if (avi_sync(s, 1) == 0)
first_packet_pos = avio_tell(pb) - 8;
avi->stream_index = -1;
avio_seek(pb, idx1_pos, SEEK_SET);
/* Read the entries and sort them in each stream component. */
for (i = 0; i < nb_index_entries; i++) {
tag = avio_rl32(pb);
flags = avio_rl32(pb);
pos = avio_rl32(pb);
len = avio_rl32(pb);
av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
i, tag, flags, pos, len);
index = ((tag & 0xff) - '0') * 10;
index += (tag >> 8 & 0xff) - '0';
if (index >= s->nb_streams)
continue;
st = s->streams[index];
ast = st->priv_data;
if (first_packet && first_packet_pos && len) {
data_offset = first_packet_pos - pos;
first_packet = 0;
}
pos += data_offset;
av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
if (pb->eof_reached)
return AVERROR_INVALIDDATA;
if (last_pos == pos)
avi->non_interleaved = 1;
else if (len || !ast->sample_size)
av_add_index_entry(st, pos, ast->cum_len, len, 0,
(flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
ast->cum_len += get_duration(ast, len);
last_pos = pos;
}
return 0;
}
/* Scan the index and consider any file with streams more than
* 2 seconds or 64MB apart non-interleaved. */
static int check_stream_max_drift(AVFormatContext *s)
{
int64_t min_pos, pos;
int i;
int *idx = av_mallocz_array(s->nb_streams, sizeof(*idx));
if (!idx)
return AVERROR(ENOMEM);
for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {
int64_t max_dts = INT64_MIN / 2;
int64_t min_dts = INT64_MAX / 2;
int64_t max_buffer = 0;
min_pos = INT64_MAX;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int n = st->nb_index_entries;
while (idx[i] < n && st->index_entries[idx[i]].pos < pos)
idx[i]++;
if (idx[i] < n) {
int64_t dts;
dts = av_rescale_q(st->index_entries[idx[i]].timestamp /
FFMAX(ast->sample_size, 1),
st->time_base, AV_TIME_BASE_Q);
min_dts = FFMIN(min_dts, dts);
min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
}
}
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
if (idx[i] && min_dts != INT64_MAX / 2) {
int64_t dts;
dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /
FFMAX(ast->sample_size, 1),
st->time_base, AV_TIME_BASE_Q);
max_dts = FFMAX(max_dts, dts);
max_buffer = FFMAX(max_buffer,
av_rescale(dts - min_dts,
st->codec->bit_rate,
AV_TIME_BASE));
}
}
if (max_dts - min_dts > 2 * AV_TIME_BASE ||
max_buffer > 1024 * 1024 * 8 * 8) {
av_free(idx);
return 1;
}
}
av_free(idx);
return 0;
}
static int guess_ni_flag(AVFormatContext *s)
{
int i;
int64_t last_start = 0;
int64_t first_end = INT64_MAX;
int64_t oldpos = avio_tell(s->pb);
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
int n = st->nb_index_entries;
unsigned int size;
if (n <= 0)
continue;
if (n >= 2) {
int64_t pos = st->index_entries[0].pos;
avio_seek(s->pb, pos + 4, SEEK_SET);
size = avio_rl32(s->pb);
if (pos + size > st->index_entries[1].pos)
last_start = INT64_MAX;
}
if (st->index_entries[0].pos > last_start)
last_start = st->index_entries[0].pos;
if (st->index_entries[n - 1].pos < first_end)
first_end = st->index_entries[n - 1].pos;
}
avio_seek(s->pb, oldpos, SEEK_SET);
if (last_start > first_end)
return 1;
return check_stream_max_drift(s);
}
static int avi_load_index(AVFormatContext *s)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
uint32_t tag, size;
int64_t pos = avio_tell(pb);
int ret = -1;
if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
goto the_end; // maybe truncated file
av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
for (;;) {
if (pb->eof_reached)
break;
tag = avio_rl32(pb);
size = avio_rl32(pb);
av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
tag & 0xff,
(tag >> 8) & 0xff,
(tag >> 16) & 0xff,
(tag >> 24) & 0xff,
size);
if (tag == MKTAG('i', 'd', 'x', '1') &&
avi_read_idx1(s, size) >= 0) {
ret = 0;
break;
}
size += (size & 1);
if (avio_skip(pb, size) < 0)
break; // something is wrong here
}
the_end:
avio_seek(pb, pos, SEEK_SET);
return ret;
}
static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
{
AVIStream *ast2 = st2->priv_data;
int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
av_free_packet(&ast2->sub_pkt);
if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
}
static int avi_read_seek(AVFormatContext *s, int stream_index,
int64_t timestamp, int flags)
{
AVIContext *avi = s->priv_data;
AVStream *st;
int i, index;
int64_t pos;
AVIStream *ast;
/* Does not matter which stream is requested dv in avi has the
* stream information in the first video stream.
*/
if (avi->dv_demux)
stream_index = 0;
if (!avi->index_loaded) {
/* we only load the index on demand */
avi_load_index(s);
avi->index_loaded = 1;
}
st = s->streams[stream_index];
ast = st->priv_data;
index = av_index_search_timestamp(st,
timestamp * FFMAX(ast->sample_size, 1),
flags);
if (index < 0)
return AVERROR_INVALIDDATA;
/* find the position */
pos = st->index_entries[index].pos;
timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",
timestamp, index, st->index_entries[index].timestamp);
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
/* One and only one real stream for DV in AVI, and it has video */
/* offsets. Calling with other stream indexes should have failed */
/* the av_index_search_timestamp call above. */
/* Feed the DV video stream version of the timestamp to the */
/* DV demux so it can synthesize correct timestamps. */
ff_dv_offset_reset(avi->dv_demux, timestamp);
avio_seek(s->pb, pos, SEEK_SET);
avi->stream_index = -1;
return 0;
}
for (i = 0; i < s->nb_streams; i++) {
AVStream *st2 = s->streams[i];
AVIStream *ast2 = st2->priv_data;
ast2->packet_size =
ast2->remaining = 0;
if (ast2->sub_ctx) {
seek_subtitle(st, st2, timestamp);
continue;
}
if (st2->nb_index_entries <= 0)
continue;
// assert(st2->codec->block_align);
assert((int64_t)st2->time_base.num * ast2->rate ==
(int64_t)st2->time_base.den * ast2->scale);
index = av_index_search_timestamp(st2,
av_rescale_q(timestamp,
st->time_base,
st2->time_base) *
FFMAX(ast2->sample_size, 1),
flags | AVSEEK_FLAG_BACKWARD);
if (index < 0)
index = 0;
if (!avi->non_interleaved) {
while (index > 0 && st2->index_entries[index].pos > pos)
index--;
while (index + 1 < st2->nb_index_entries &&
st2->index_entries[index].pos < pos)
index++;
}
av_dlog(s, "%"PRId64" %d %"PRId64"\n",
timestamp, index, st2->index_entries[index].timestamp);
/* extract the current frame number */
ast2->frame_offset = st2->index_entries[index].timestamp;
}
/* do the seek */
avio_seek(s->pb, pos, SEEK_SET);
avi->stream_index = -1;
return 0;
}
static int avi_read_close(AVFormatContext *s)
{
int i;
AVIContext *avi = s->priv_data;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
if (ast) {
if (ast->sub_ctx) {
av_freep(&ast->sub_ctx->pb);
avformat_close_input(&ast->sub_ctx);
}
av_free(ast->sub_buffer);
av_free_packet(&ast->sub_pkt);
}
}
av_free(avi->dv_demux);
return 0;
}
static int avi_probe(AVProbeData *p)
{
int i;
/* check file header */
for (i = 0; avi_headers[i][0]; i++)
if (!memcmp(p->buf, avi_headers[i], 4) &&
!memcmp(p->buf + 8, avi_headers[i] + 4, 4))
return AVPROBE_SCORE_MAX;
return 0;
}
AVInputFormat ff_avi_demuxer = {
.name = "avi",
.long_name = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),
.priv_data_size = sizeof(AVIContext),
.extensions = "avi",
.read_probe = avi_probe,
.read_header = avi_read_header,
.read_packet = avi_read_packet,
.read_close = avi_read_close,
.read_seek = avi_read_seek,
};
Reference in New Issue View Git Blame Copy Permalink