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ffmpeg/libavformat/flvdec.c

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/*
* 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,
};
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