virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-12 19:18:44 +02:00
Code Issues Releases Activity
a9e1f2cc61
FFmpeg/libavformat/flvdec.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

1023 lines
34 KiB
C
Raw Blame History

/*
* FLV demuxer
* Copyright (c) 2003 The Libav Project
*
* This demuxer will generate a 1 byte extradata for VP6F content.
* It is composed of:
* - upper 4bits: difference between encoded width and visible width
* - lower 4bits: difference between encoded height and visible height
*
* 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 "libavutil/avstring.h"
#include "libavutil/channel_layout.h"
#include "libavutil/dict.h"
#include "libavutil/opt.h"
#include "libavutil/intfloat.h"
#include "libavutil/mathematics.h"
#include "libavcodec/bytestream.h"
#include "libavcodec/mpeg4audio.h"
#include "avformat.h"
#include "internal.h"
#include "avio_internal.h"
#include "flv.h"
#define KEYFRAMES_TAG "keyframes"
#define KEYFRAMES_TIMESTAMP_TAG "times"
#define KEYFRAMES_BYTEOFFSET_TAG "filepositions"
#define VALIDATE_INDEX_TS_THRESH 2500
typedef struct FLVContext {
const AVClass *class; ///< Class for private options.
int trust_metadata; ///< configure streams according onMetaData
int wrong_dts; ///< wrong dts due to negative cts
uint8_t *new_extradata[2];
int new_extradata_size[2];
int last_sample_rate;
int last_channels;
struct {
int64_t dts;
int64_t pos;
} validate_index[2];
int validate_next;
int validate_count;
int searched_for_end;
} FLVContext;
static int flv_probe(AVProbeData *p)
{
const uint8_t *d;
d = p->buf;
if (d[0] == 'F' &&
d[1] == 'L' &&
d[2] == 'V' &&
d[3] < 5 && d[5] == 0 &&
AV_RB32(d + 5) > 8) {
return AVPROBE_SCORE_MAX;
}
return 0;
}
static AVStream *create_stream(AVFormatContext *s, int codec_type)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return NULL;
st->codecpar->codec_type = codec_type;
avpriv_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
return st;
}
static int flv_same_audio_codec(AVCodecParameters *apar, int flags)
{
int bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
int flv_codecid = flags & FLV_AUDIO_CODECID_MASK;
int codec_id;
if (!apar->codec_id && !apar->codec_tag)
return 1;
if (apar->bits_per_coded_sample != bits_per_coded_sample)
return 0;
switch (flv_codecid) {
// no distinction between S16 and S8 PCM codec flags
case FLV_CODECID_PCM:
codec_id = bits_per_coded_sample == 8
? AV_CODEC_ID_PCM_U8
#if HAVE_BIGENDIAN
: AV_CODEC_ID_PCM_S16BE;
#else
: AV_CODEC_ID_PCM_S16LE;
#endif
return codec_id == apar->codec_id;
case FLV_CODECID_PCM_LE:
codec_id = bits_per_coded_sample == 8
? AV_CODEC_ID_PCM_U8
: AV_CODEC_ID_PCM_S16LE;
return codec_id == apar->codec_id;
case FLV_CODECID_AAC:
return apar->codec_id == AV_CODEC_ID_AAC;
case FLV_CODECID_ADPCM:
return apar->codec_id == AV_CODEC_ID_ADPCM_SWF;
case FLV_CODECID_SPEEX:
return apar->codec_id == AV_CODEC_ID_SPEEX;
case FLV_CODECID_MP3:
return apar->codec_id == AV_CODEC_ID_MP3;
case FLV_CODECID_NELLYMOSER_8KHZ_MONO:
case FLV_CODECID_NELLYMOSER_16KHZ_MONO:
case FLV_CODECID_NELLYMOSER:
return apar->codec_id == AV_CODEC_ID_NELLYMOSER;
case FLV_CODECID_PCM_MULAW:
return apar->sample_rate == 8000 &&
apar->codec_id == AV_CODEC_ID_PCM_MULAW;
case FLV_CODECID_PCM_ALAW:
return apar->sample_rate == 8000 &&
apar->codec_id == AV_CODEC_ID_PCM_ALAW;
default:
return apar->codec_tag == (flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
}
}
static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream,
AVCodecParameters *apar, int flv_codecid)
{
switch (flv_codecid) {
// no distinction between S16 and S8 PCM codec flags
case FLV_CODECID_PCM:
apar->codec_id = apar->bits_per_coded_sample == 8
? AV_CODEC_ID_PCM_U8
#if HAVE_BIGENDIAN
: AV_CODEC_ID_PCM_S16BE;
#else
: AV_CODEC_ID_PCM_S16LE;
#endif
break;
case FLV_CODECID_PCM_LE:
apar->codec_id = apar->bits_per_coded_sample == 8
? AV_CODEC_ID_PCM_U8
: AV_CODEC_ID_PCM_S16LE;
break;
case FLV_CODECID_AAC:
apar->codec_id = AV_CODEC_ID_AAC;
break;
case FLV_CODECID_ADPCM:
apar->codec_id = AV_CODEC_ID_ADPCM_SWF;
break;
case FLV_CODECID_SPEEX:
apar->codec_id = AV_CODEC_ID_SPEEX;
apar->sample_rate = 16000;
break;
case FLV_CODECID_MP3:
apar->codec_id = AV_CODEC_ID_MP3;
astream->need_parsing = AVSTREAM_PARSE_FULL;
break;
case FLV_CODECID_NELLYMOSER_8KHZ_MONO:
// in case metadata does not otherwise declare samplerate
apar->sample_rate = 8000;
apar->codec_id = AV_CODEC_ID_NELLYMOSER;
break;
case FLV_CODECID_NELLYMOSER_16KHZ_MONO:
apar->sample_rate = 16000;
apar->codec_id = AV_CODEC_ID_NELLYMOSER;
break;
case FLV_CODECID_NELLYMOSER:
apar->codec_id = AV_CODEC_ID_NELLYMOSER;
break;
case FLV_CODECID_PCM_MULAW:
apar->sample_rate = 8000;
apar->codec_id = AV_CODEC_ID_PCM_MULAW;
break;
case FLV_CODECID_PCM_ALAW:
apar->sample_rate = 8000;
apar->codec_id = AV_CODEC_ID_PCM_ALAW;
break;
default:
av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n",
flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
apar->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;
}
}
static int flv_same_video_codec(AVCodecParameters *vpar, int flags)
{
int flv_codecid = flags & FLV_VIDEO_CODECID_MASK;
if (!vpar->codec_id && !vpar->codec_tag)
return 1;
switch (flv_codecid) {
case FLV_CODECID_H263:
return vpar->codec_id == AV_CODEC_ID_FLV1;
case FLV_CODECID_SCREEN:
return vpar->codec_id == AV_CODEC_ID_FLASHSV;
case FLV_CODECID_SCREEN2:
return vpar->codec_id == AV_CODEC_ID_FLASHSV2;
case FLV_CODECID_VP6:
return vpar->codec_id == AV_CODEC_ID_VP6F;
case FLV_CODECID_VP6A:
return vpar->codec_id == AV_CODEC_ID_VP6A;
case FLV_CODECID_H264:
return vpar->codec_id == AV_CODEC_ID_H264;
default:
return vpar->codec_tag == flv_codecid;
}
}
static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream,
int flv_codecid, int read)
{
AVCodecParameters *par = vstream->codecpar;
switch (flv_codecid) {
case FLV_CODECID_H263:
par->codec_id = AV_CODEC_ID_FLV1;
break;
case FLV_CODECID_SCREEN:
par->codec_id = AV_CODEC_ID_FLASHSV;
break;
case FLV_CODECID_SCREEN2:
par->codec_id = AV_CODEC_ID_FLASHSV2;
break;
case FLV_CODECID_VP6:
par->codec_id = AV_CODEC_ID_VP6F;
case FLV_CODECID_VP6A:
if (flv_codecid == FLV_CODECID_VP6A)
par->codec_id = AV_CODEC_ID_VP6A;
if (read) {
if (par->extradata_size != 1) {
par->extradata = av_malloc(1);
if (par->extradata)
par->extradata_size = 1;
}
if (par->extradata)
par->extradata[0] = avio_r8(s->pb);
else
avio_skip(s->pb, 1);
}
return 1; // 1 byte body size adjustment for flv_read_packet()
case FLV_CODECID_H264:
par->codec_id = AV_CODEC_ID_H264;
return 3; // not 4, reading packet type will consume one byte
default:
av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid);
par->codec_tag = flv_codecid;
}
return 0;
}
static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize)
{
int length = avio_rb16(ioc);
if (length >= buffsize) {
avio_skip(ioc, length);
return -1;
}
avio_read(ioc, buffer, length);
buffer[length] = '\0';
return length;
}
static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc,
AVStream *vstream, int64_t max_pos)
{
FLVContext *flv = s->priv_data;
unsigned int arraylen = 0, timeslen = 0, fileposlen = 0, i;
double num_val;
char str_val[256];
int64_t *times = NULL;
int64_t *filepositions = NULL;
int ret = AVERROR(ENOSYS);
int64_t initial_pos = avio_tell(ioc);
if (s->flags & AVFMT_FLAG_IGNIDX)
return 0;
while (avio_tell(ioc) < max_pos - 2 &&
amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
int64_t *current_array;
// Expect array object in context
if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)
break;
arraylen = avio_rb32(ioc);
if (arraylen >> 28)
break;
/* Expect only 'times' or 'filepositions' sub-arrays in other
* case refuse to use such metadata for indexing. */
if (!strcmp(KEYFRAMES_TIMESTAMP_TAG, str_val) && !times) {
if (!(times = av_mallocz(sizeof(*times) * arraylen))) {
ret = AVERROR(ENOMEM);
goto finish;
}
timeslen = arraylen;
current_array = times;
} else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) &&
!filepositions) {
if (!(filepositions = av_mallocz(sizeof(*filepositions) * arraylen))) {
ret = AVERROR(ENOMEM);
goto finish;
}
fileposlen = arraylen;
current_array = filepositions;
} else
// unexpected metatag inside keyframes, will not use such
// metadata for indexing
break;
for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)
goto finish;
num_val = av_int2double(avio_rb64(ioc));
current_array[i] = num_val;
}
if (times && filepositions) {
// All done, exiting at a position allowing amf_parse_object
// to finish parsing the object
ret = 0;
break;
}
}
if (!ret && timeslen == fileposlen) {
for (i = 0; i < fileposlen; i++) {
av_add_index_entry(vstream, filepositions[i], times[i] * 1000,
0, 0, AVINDEX_KEYFRAME);
if (i < 2) {
flv->validate_index[i].pos = filepositions[i];
flv->validate_index[i].dts = times[i] * 1000;
flv->validate_count = i + 1;
}
}
} else
av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n");
finish:
av_freep(&times);
av_freep(&filepositions);
// If we got unexpected data, but successfully reset back to
// the start pos, the caller can continue parsing
if (ret < 0 && avio_seek(ioc, initial_pos, SEEK_SET) > 0)
return 0;
return ret;
}
static int amf_parse_object(AVFormatContext *s, AVStream *astream,
AVStream *vstream, const char *key,
int64_t max_pos, int depth)
{
AVCodecParameters *apar, *vpar;
FLVContext *flv = s->priv_data;
AVIOContext *ioc;
AMFDataType amf_type;
char str_val[256];
double num_val;
num_val = 0;
ioc = s->pb;
amf_type = avio_r8(ioc);
switch (amf_type) {
case AMF_DATA_TYPE_NUMBER:
num_val = av_int2double(avio_rb64(ioc));
break;
case AMF_DATA_TYPE_BOOL:
num_val = avio_r8(ioc);
break;
case AMF_DATA_TYPE_STRING:
if (amf_get_string(ioc, str_val, sizeof(str_val)) < 0)
return -1;
break;
case AMF_DATA_TYPE_OBJECT:
if ((vstream || astream) && key &&
!strcmp(KEYFRAMES_TAG, key) && depth == 1)
if (parse_keyframes_index(s, ioc, vstream ? vstream : astream,
max_pos) < 0)
return -1;
while (avio_tell(ioc) < max_pos - 2 &&
amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
if (amf_parse_object(s, astream, vstream, str_val, max_pos,
depth + 1) < 0)
return -1; // if we couldn't skip, bomb out.
if (avio_r8(ioc) != AMF_END_OF_OBJECT)
return -1;
break;
case AMF_DATA_TYPE_NULL:
case AMF_DATA_TYPE_UNDEFINED:
case AMF_DATA_TYPE_UNSUPPORTED:
break; // these take up no additional space
case AMF_DATA_TYPE_MIXEDARRAY:
avio_skip(ioc, 4); // skip 32-bit max array index
while (avio_tell(ioc) < max_pos - 2 &&
amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
// this is the only case in which we would want a nested
// parse to not skip over the object
if (amf_parse_object(s, astream, vstream, str_val, max_pos,
depth + 1) < 0)
return -1;
if (avio_r8(ioc) != AMF_END_OF_OBJECT)
return -1;
break;
case AMF_DATA_TYPE_ARRAY:
{
unsigned int arraylen, i;
arraylen = avio_rb32(ioc);
for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++)
if (amf_parse_object(s, NULL, NULL, NULL, max_pos,
depth + 1) < 0)
return -1; // if we couldn't skip, bomb out.
}
break;
case AMF_DATA_TYPE_DATE:
avio_skip(ioc, 8 + 2); // timestamp (double) and UTC offset (int16)
break;
default: // unsupported type, we couldn't skip
return -1;
}
if (key) {
// stream info doesn't live any deeper than the first object
if (depth == 1) {
apar = astream ? astream->codecpar : NULL;
vpar = vstream ? vstream->codecpar : NULL;
if (amf_type == AMF_DATA_TYPE_NUMBER ||
amf_type == AMF_DATA_TYPE_BOOL) {
if (!strcmp(key, "duration"))
s->duration = num_val * AV_TIME_BASE;
else if (!strcmp(key, "videodatarate") && vpar &&
0 <= (int)(num_val * 1024.0))
vpar->bit_rate = num_val * 1024.0;
else if (!strcmp(key, "audiodatarate") && apar &&
0 <= (int)(num_val * 1024.0))
apar->bit_rate = num_val * 1024.0;
else if (!strcmp(key, "datastream")) {
AVStream *st = create_stream(s, AVMEDIA_TYPE_DATA);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_TEXT;
} else if (flv->trust_metadata) {
if (!strcmp(key, "videocodecid") && vpar) {
flv_set_video_codec(s, vstream, num_val, 0);
} else if (!strcmp(key, "audiocodecid") && apar) {
int id = ((int)num_val) << FLV_AUDIO_CODECID_OFFSET;
flv_set_audio_codec(s, astream, apar, id);
} else if (!strcmp(key, "audiosamplerate") && apar) {
apar->sample_rate = num_val;
} else if (!strcmp(key, "audiosamplesize") && apar) {
apar->bits_per_coded_sample = num_val;
} else if (!strcmp(key, "stereo") && apar) {
apar->channels = num_val + 1;
apar->channel_layout = apar->channels == 2 ?
AV_CH_LAYOUT_STEREO :
AV_CH_LAYOUT_MONO;
} else if (!strcmp(key, "width") && vpar) {
vpar->width = num_val;
} else if (!strcmp(key, "height") && vpar) {
vpar->height = num_val;
}
}
}
}
if (!strcmp(key, "duration") ||
!strcmp(key, "filesize") ||
!strcmp(key, "width") ||
!strcmp(key, "height") ||
!strcmp(key, "videodatarate") ||
!strcmp(key, "framerate") ||
!strcmp(key, "videocodecid") ||
!strcmp(key, "audiodatarate") ||
!strcmp(key, "audiosamplerate") ||
!strcmp(key, "audiosamplesize") ||
!strcmp(key, "stereo") ||
!strcmp(key, "audiocodecid") ||
!strcmp(key, "datastream"))
return 0;
s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
if (amf_type == AMF_DATA_TYPE_BOOL) {
av_strlcpy(str_val, num_val > 0 ? "true" : "false",
sizeof(str_val));
av_dict_set(&s->metadata, key, str_val, 0);
} else if (amf_type == AMF_DATA_TYPE_NUMBER) {
snprintf(str_val, sizeof(str_val), "%.f", num_val);
av_dict_set(&s->metadata, key, str_val, 0);
} else if (amf_type == AMF_DATA_TYPE_STRING)
av_dict_set(&s->metadata, key, str_val, 0);
}
return 0;
}
static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)
{
AMFDataType type;
AVStream *stream, *astream, *vstream;
AVIOContext *ioc;
int i;
// only needs to hold the string "onMetaData".
// Anything longer is something we don't want.
char buffer[11];
astream = NULL;
vstream = NULL;
ioc = s->pb;
// first object needs to be "onMetaData" string
type = avio_r8(ioc);
if (type != AMF_DATA_TYPE_STRING ||
amf_get_string(ioc, buffer, sizeof(buffer)) < 0)
return -1;
if (!strcmp(buffer, "onTextData"))
return 1;
if (strcmp(buffer, "onMetaData") && strcmp(buffer, "onCuePoint"))
return -1;
// find the streams now so that amf_parse_object doesn't need to do
// the lookup every time it is called.
for (i = 0; i < s->nb_streams; i++) {
stream = s->streams[i];
if (stream->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
astream = stream;
else if (stream->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
vstream = stream;
}
// parse the second object (we want a mixed array)
if (amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
return -1;
return 0;
}
static int flv_read_header(AVFormatContext *s)
{
int offset;
avio_skip(s->pb, 4);
avio_r8(s->pb); // flags
s->ctx_flags |= AVFMTCTX_NOHEADER;
offset = avio_rb32(s->pb);
avio_seek(s->pb, offset, SEEK_SET);
avio_skip(s->pb, 4);
s->start_time = 0;
return 0;
}
static int flv_read_close(AVFormatContext *s)
{
FLVContext *flv = s->priv_data;
av_freep(&flv->new_extradata[0]);
av_freep(&flv->new_extradata[1]);
return 0;
}
static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size)
{
av_free(st->codecpar->extradata);
st->codecpar->extradata = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
if (!st->codecpar->extradata)
return AVERROR(ENOMEM);
st->codecpar->extradata_size = size;
avio_read(s->pb, st->codecpar->extradata, st->codecpar->extradata_size);
return 0;
}
static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,
int size)
{
av_free(flv->new_extradata[stream]);
flv->new_extradata[stream] = av_mallocz(size +
AV_INPUT_BUFFER_PADDING_SIZE);
if (!flv->new_extradata[stream])
return AVERROR(ENOMEM);
flv->new_extradata_size[stream] = size;
avio_read(pb, flv->new_extradata[stream], size);
return 0;
}
static void clear_index_entries(AVFormatContext *s, int64_t pos)
{
int i, j, out;
av_log(s, AV_LOG_WARNING,
"Found invalid index entries, clearing the index.\n");
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
/* Remove all index entries that point to >= pos */
out = 0;
for (j = 0; j < st->nb_index_entries; j++)
if (st->index_entries[j].pos < pos)
st->index_entries[out++] = st->index_entries[j];
st->nb_index_entries = out;
}
}
static int amf_skip_tag(AVIOContext *pb, AMFDataType type)
{
int nb = -1, ret, parse_name = 1;
switch (type) {
case AMF_DATA_TYPE_NUMBER:
avio_skip(pb, 8);
break;
case AMF_DATA_TYPE_BOOL:
avio_skip(pb, 1);
break;
case AMF_DATA_TYPE_STRING:
avio_skip(pb, avio_rb16(pb));
break;
case AMF_DATA_TYPE_ARRAY:
parse_name = 0;
case AMF_DATA_TYPE_MIXEDARRAY:
nb = avio_rb32(pb);
case AMF_DATA_TYPE_OBJECT:
while(!pb->eof_reached && (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY)) {
if (parse_name) {
int size = avio_rb16(pb);
if (!size) {
avio_skip(pb, 1);
break;
}
avio_skip(pb, size);
}
if ((ret = amf_skip_tag(pb, avio_r8(pb))) < 0)
return ret;
}
break;
case AMF_DATA_TYPE_NULL:
case AMF_DATA_TYPE_OBJECT_END:
break;
default:
return AVERROR_INVALIDDATA;
}
return 0;
}
static int flv_data_packet(AVFormatContext *s, AVPacket *pkt,
int64_t dts, int64_t next)
{
AVIOContext *pb = s->pb;
AVStream *st = NULL;
char buf[20];
int ret = AVERROR_INVALIDDATA;
int i, length = -1;
switch (avio_r8(pb)) {
case AMF_DATA_TYPE_MIXEDARRAY:
avio_seek(pb, 4, SEEK_CUR);
case AMF_DATA_TYPE_OBJECT:
break;
default:
goto skip;
}
while ((ret = amf_get_string(pb, buf, sizeof(buf))) > 0) {
AMFDataType type = avio_r8(pb);
if (type == AMF_DATA_TYPE_STRING && !strcmp(buf, "text")) {
length = avio_rb16(pb);
ret = av_get_packet(pb, pkt, length);
if (ret < 0)
goto skip;
else
break;
} else {
if ((ret = amf_skip_tag(pb, type)) < 0)
goto skip;
}
}
if (length < 0) {
ret = AVERROR_INVALIDDATA;
goto skip;
}
for (i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
if (st->codecpar->codec_type == AVMEDIA_TYPE_DATA)
break;
}
if (i == s->nb_streams) {
st = create_stream(s, AVMEDIA_TYPE_DATA);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_TEXT;
}
pkt->dts = dts;
pkt->pts = dts;
pkt->size = ret;
pkt->stream_index = st->index;
pkt->flags |= AV_PKT_FLAG_KEY;
skip:
avio_seek(s->pb, next + 4, SEEK_SET);
return ret;
}
static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
{
FLVContext *flv = s->priv_data;
int ret, i, size, flags, is_audio;
enum FlvTagType type;
int64_t next, pos;
int64_t dts, pts = AV_NOPTS_VALUE;
int sample_rate = 0, channels = 0;
AVStream *st = NULL;
/* pkt size is repeated at end. skip it */
for (;; avio_skip(s->pb, 4)) {
pos = avio_tell(s->pb);
type = avio_r8(s->pb);
size = avio_rb24(s->pb);
dts = avio_rb24(s->pb);
dts |= avio_r8(s->pb) << 24;
av_log(s, AV_LOG_TRACE, "type:%d, size:%d, dts:%"PRId64"\n", type, size, dts);
if (s->pb->eof_reached)
return AVERROR_EOF;
avio_skip(s->pb, 3); /* stream id, always 0 */
flags = 0;
if (flv->validate_next < flv->validate_count) {
int64_t validate_pos = flv->validate_index[flv->validate_next].pos;
if (pos == validate_pos) {
if (FFABS(dts - flv->validate_index[flv->validate_next].dts) <=
VALIDATE_INDEX_TS_THRESH) {
flv->validate_next++;
} else {
clear_index_entries(s, validate_pos);
flv->validate_count = 0;
}
} else if (pos > validate_pos) {
clear_index_entries(s, validate_pos);
flv->validate_count = 0;
}
}
if (size == 0)
continue;
next = size + avio_tell(s->pb);
if (type == FLV_TAG_TYPE_AUDIO) {
is_audio = 1;
flags = avio_r8(s->pb);
size--;
} else if (type == FLV_TAG_TYPE_VIDEO) {
is_audio = 0;
flags = avio_r8(s->pb);
size--;
if ((flags & 0xf0) == 0x50) /* video info / command frame */
goto skip;
} else {
if (type == FLV_TAG_TYPE_META && size > 13 + 1 + 4)
if (flv_read_metabody(s, next) > 0) {
return flv_data_packet(s, pkt, dts, next);
} else /* skip packet */
av_log(s, AV_LOG_DEBUG,
"Skipping flv packet: type %d, size %d, flags %d.\n",
type, size, flags);
skip:
avio_seek(s->pb, next, SEEK_SET);
continue;
}
/* skip empty data packets */
if (!size)
continue;
/* now find stream */
for (i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
if (is_audio && st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
if (flv_same_audio_codec(st->codecpar, flags))
break;
} else if (!is_audio &&
st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
if (flv_same_video_codec(st->codecpar, flags))
break;
}
}
if (i == s->nb_streams) {
st = create_stream(s, is_audio ? AVMEDIA_TYPE_AUDIO
: AVMEDIA_TYPE_VIDEO);
if (!st)
return AVERROR(ENOMEM);
}
av_log(s, AV_LOG_TRACE, "%d %X %d \n", is_audio, flags, st->discard);
if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||
is_audio)
av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
if ((st->discard >= AVDISCARD_NONKEY &&
!((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || is_audio)) ||
(st->discard >= AVDISCARD_BIDIR &&
((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio)) ||
st->discard >= AVDISCARD_ALL) {
avio_seek(s->pb, next, SEEK_SET);
continue;
}
break;
}
// if not streamed and no duration from metadata then seek to end to find
// the duration from the timestamps
if (s->pb->seekable && (!s->duration || s->duration == AV_NOPTS_VALUE) &&
!flv->searched_for_end) {
int size;
const int64_t pos = avio_tell(s->pb);
// Read the last 4 bytes of the file, this should be the size of the
// previous FLV tag. Use the timestamp of its payload as duration.
const int64_t fsize = avio_size(s->pb);
avio_seek(s->pb, fsize - 4, SEEK_SET);
size = avio_rb32(s->pb);
if (size > 0 && size < fsize) {
// Seek to the start of the last FLV tag at position (fsize - 4 - size)
// but skip the byte indicating the type.
avio_seek(s->pb, fsize - 3 - size, SEEK_SET);
if (size == avio_rb24(s->pb) + 11) {
uint32_t ts = avio_rb24(s->pb);
ts |= avio_r8(s->pb) << 24;
s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
}
}
avio_seek(s->pb, pos, SEEK_SET);
flv->searched_for_end = 1;
}
if (is_audio) {
int bits_per_coded_sample;
channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
sample_rate = 44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >>
FLV_AUDIO_SAMPLERATE_OFFSET) >> 3;
bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
if (!st->codecpar->channels || !st->codecpar->sample_rate ||
!st->codecpar->bits_per_coded_sample) {
st->codecpar->channels = channels;
st->codecpar->channel_layout = channels == 1
? AV_CH_LAYOUT_MONO
: AV_CH_LAYOUT_STEREO;
st->codecpar->sample_rate = sample_rate;
st->codecpar->bits_per_coded_sample = bits_per_coded_sample;
}
if (!st->codecpar->codec_id) {
flv_set_audio_codec(s, st, st->codecpar,
flags & FLV_AUDIO_CODECID_MASK);
flv->last_sample_rate =
sample_rate = st->codecpar->sample_rate;
flv->last_channels =
channels = st->codecpar->channels;
} else {
AVCodecParameters *par = avcodec_parameters_alloc();
if (!par) {
ret = AVERROR(ENOMEM);
goto leave;
}
par->sample_rate = sample_rate;
par->bits_per_coded_sample = bits_per_coded_sample;
flv_set_audio_codec(s, st, par, flags & FLV_AUDIO_CODECID_MASK);
sample_rate = par->sample_rate;
avcodec_parameters_free(&par);
}
} else {
size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK, 1);
}
if (st->codecpar->codec_id == AV_CODEC_ID_AAC ||
st->codecpar->codec_id == AV_CODEC_ID_H264) {
int type = avio_r8(s->pb);
size--;
if (st->codecpar->codec_id == AV_CODEC_ID_H264) {
// sign extension
int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;
pts = dts + cts;
if (cts < 0 && !flv->wrong_dts) { // dts might be wrong
flv->wrong_dts = 1;
av_log(s, AV_LOG_WARNING,
"Negative cts, previous timestamps might be wrong.\n");
}
}
if (type == 0) {
if (st->codecpar->extradata) {
if ((ret = flv_queue_extradata(flv, s->pb, is_audio, size)) < 0)
return ret;
ret = AVERROR(EAGAIN);
goto leave;
}
if ((ret = flv_get_extradata(s, st, size)) < 0)
return ret;
if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
MPEG4AudioConfig cfg;
/* Workaround for buggy Omnia A/XE encoder */
AVDictionaryEntry *t = av_dict_get(s->metadata, "Encoder", NULL, 0);
if (t && !strcmp(t->value, "Omnia A/XE"))
st->codecpar->extradata_size = 2;
avpriv_mpeg4audio_get_config(&cfg, st->codecpar->extradata,
st->codecpar->extradata_size * 8, 1);
st->codecpar->channels = cfg.channels;
st->codecpar->channel_layout = 0;
if (cfg.ext_sample_rate)
st->codecpar->sample_rate = cfg.ext_sample_rate;
else
st->codecpar->sample_rate = cfg.sample_rate;
av_log(s, AV_LOG_TRACE, "mp4a config channels %d sample rate %d\n",
st->codecpar->channels, st->codecpar->sample_rate);
}
ret = AVERROR(EAGAIN);
goto leave;
}
}
/* skip empty data packets */
if (!size) {
ret = AVERROR(EAGAIN);
goto leave;
}
ret = av_get_packet(s->pb, pkt, size);
if (ret < 0)
return AVERROR(EIO);
/* note: we need to modify the packet size here to handle the last
* packet */
pkt->size = ret;
pkt->dts = dts;
pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
pkt->stream_index = st->index;
if (flv->new_extradata[is_audio]) {
uint8_t *side = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
flv->new_extradata_size[is_audio]);
if (side) {
memcpy(side, flv->new_extradata[is_audio],
flv->new_extradata_size[is_audio]);
av_freep(&flv->new_extradata[is_audio]);
flv->new_extradata_size[is_audio] = 0;
}
}
if (is_audio && (sample_rate != flv->last_sample_rate ||
channels != flv->last_channels)) {
flv->last_sample_rate = sample_rate;
flv->last_channels = channels;
ff_add_param_change(pkt, channels, 0, sample_rate, 0, 0);
}
if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY))
pkt->flags |= AV_PKT_FLAG_KEY;
leave:
avio_skip(s->pb, 4);
return ret;
}
static int flv_read_seek(AVFormatContext *s, int stream_index,
int64_t ts, int flags)
{
FLVContext *flv = s->priv_data;
flv->validate_count = 0;
return avio_seek_time(s->pb, stream_index, ts, flags);
}
#define OFFSET(x) offsetof(FLVContext, x)
#define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
static const AVOption options[] = {
{ "flv_metadata", "Allocate streams according to the onMetaData array", OFFSET(trust_metadata), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VD },
{ NULL }
};
static const AVClass class = {
.class_name = "flvdec",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVInputFormat ff_flv_demuxer = {
.name = "flv",
.long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
.priv_data_size = sizeof(FLVContext),
.read_probe = flv_probe,
.read_header = flv_read_header,
.read_packet = flv_read_packet,
.read_seek = flv_read_seek,
.read_close = flv_read_close,
.extensions = "flv",
.priv_class = &class,
};
Reference in New Issue View Git Blame Copy Permalink