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

1921 lines
59 KiB
C
Raw Blame History

/*
* MPEG2 transport stream (aka DVB) demuxer
* Copyright (c) 2002-2003 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
//#define DEBUG
//#define DEBUG_SEEK
//#define USE_SYNCPOINT_SEARCH
#include "libavutil/crc.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/log.h"
#include "libavutil/dict.h"
#include "libavutil/opt.h"
#include "libavcodec/bytestream.h"
#include "avformat.h"
#include "mpegts.h"
#include "internal.h"
#include "avio_internal.h"
#include "seek.h"
#include "mpeg.h"
#include "isom.h"
/* maximum size in which we look for synchronisation if
synchronisation is lost */
#define MAX_RESYNC_SIZE 65536
#define MAX_PES_PAYLOAD 200*1024
enum MpegTSFilterType {
MPEGTS_PES,
MPEGTS_SECTION,
};
typedef struct MpegTSFilter MpegTSFilter;
typedef int PESCallback(MpegTSFilter *f, const uint8_t *buf, int len, int is_start, int64_t pos);
typedef struct MpegTSPESFilter {
PESCallback *pes_cb;
void *opaque;
} MpegTSPESFilter;
typedef void SectionCallback(MpegTSFilter *f, const uint8_t *buf, int len);
typedef void SetServiceCallback(void *opaque, int ret);
typedef struct MpegTSSectionFilter {
int section_index;
int section_h_size;
uint8_t *section_buf;
unsigned int check_crc:1;
unsigned int end_of_section_reached:1;
SectionCallback *section_cb;
void *opaque;
} MpegTSSectionFilter;
struct MpegTSFilter {
int pid;
int last_cc; /* last cc code (-1 if first packet) */
enum MpegTSFilterType type;
union {
MpegTSPESFilter pes_filter;
MpegTSSectionFilter section_filter;
} u;
};
#define MAX_PIDS_PER_PROGRAM 64
struct Program {
unsigned int id; //program id/service id
unsigned int nb_pids;
unsigned int pids[MAX_PIDS_PER_PROGRAM];
};
struct MpegTSContext {
const AVClass *class;
/* user data */
AVFormatContext *stream;
/** raw packet size, including FEC if present */
int raw_packet_size;
int pos47;
/** if true, all pids are analyzed to find streams */
int auto_guess;
/** compute exact PCR for each transport stream packet */
int mpeg2ts_compute_pcr;
int64_t cur_pcr; /**< used to estimate the exact PCR */
int pcr_incr; /**< used to estimate the exact PCR */
/* data needed to handle file based ts */
/** stop parsing loop */
int stop_parse;
/** packet containing Audio/Video data */
AVPacket *pkt;
/** to detect seek */
int64_t last_pos;
/******************************************/
/* private mpegts data */
/* scan context */
/** structure to keep track of Program->pids mapping */
unsigned int nb_prg;
struct Program *prg;
/** filters for various streams specified by PMT + for the PAT and PMT */
MpegTSFilter *pids[NB_PID_MAX];
};
static const AVOption options[] = {
{"compute_pcr", "Compute exact PCR for each transport stream packet.", offsetof(MpegTSContext, mpeg2ts_compute_pcr), FF_OPT_TYPE_INT,
{.dbl = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
{ NULL },
};
static const AVClass mpegtsraw_class = {
.class_name = "mpegtsraw demuxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
/* TS stream handling */
enum MpegTSState {
MPEGTS_HEADER = 0,
MPEGTS_PESHEADER,
MPEGTS_PESHEADER_FILL,
MPEGTS_PAYLOAD,
MPEGTS_SKIP,
};
/* enough for PES header + length */
#define PES_START_SIZE 6
#define PES_HEADER_SIZE 9
#define MAX_PES_HEADER_SIZE (9 + 255)
typedef struct PESContext {
int pid;
int pcr_pid; /**< if -1 then all packets containing PCR are considered */
int stream_type;
MpegTSContext *ts;
AVFormatContext *stream;
AVStream *st;
AVStream *sub_st; /**< stream for the embedded AC3 stream in HDMV TrueHD */
enum MpegTSState state;
/* used to get the format */
int data_index;
int total_size;
int pes_header_size;
int extended_stream_id;
int64_t pts, dts;
int64_t ts_packet_pos; /**< position of first TS packet of this PES packet */
uint8_t header[MAX_PES_HEADER_SIZE];
uint8_t *buffer;
} PESContext;
extern AVInputFormat ff_mpegts_demuxer;
static void clear_program(MpegTSContext *ts, unsigned int programid)
{
int i;
for(i=0; i<ts->nb_prg; i++)
if(ts->prg[i].id == programid)
ts->prg[i].nb_pids = 0;
}
static void clear_programs(MpegTSContext *ts)
{
av_freep(&ts->prg);
ts->nb_prg=0;
}
static void add_pat_entry(MpegTSContext *ts, unsigned int programid)
{
struct Program *p;
void *tmp = av_realloc(ts->prg, (ts->nb_prg+1)*sizeof(struct Program));
if(!tmp)
return;
ts->prg = tmp;
p = &ts->prg[ts->nb_prg];
p->id = programid;
p->nb_pids = 0;
ts->nb_prg++;
}
static void add_pid_to_pmt(MpegTSContext *ts, unsigned int programid, unsigned int pid)
{
int i;
struct Program *p = NULL;
for(i=0; i<ts->nb_prg; i++) {
if(ts->prg[i].id == programid) {
p = &ts->prg[i];
break;
}
}
if(!p)
return;
if(p->nb_pids >= MAX_PIDS_PER_PROGRAM)
return;
p->pids[p->nb_pids++] = pid;
}
static void set_pcr_pid(AVFormatContext *s, unsigned int programid, unsigned int pid)
{
int i;
for(i=0; i<s->nb_programs; i++) {
if(s->programs[i]->id == programid) {
s->programs[i]->pcr_pid = pid;
break;
}
}
}
/**
* \brief discard_pid() decides if the pid is to be discarded according
* to caller's programs selection
* \param ts : - TS context
* \param pid : - pid
* \return 1 if the pid is only comprised in programs that have .discard=AVDISCARD_ALL
* 0 otherwise
*/
static int discard_pid(MpegTSContext *ts, unsigned int pid)
{
int i, j, k;
int used = 0, discarded = 0;
struct Program *p;
for(i=0; i<ts->nb_prg; i++) {
p = &ts->prg[i];
for(j=0; j<p->nb_pids; j++) {
if(p->pids[j] != pid)
continue;
//is program with id p->id set to be discarded?
for(k=0; k<ts->stream->nb_programs; k++) {
if(ts->stream->programs[k]->id == p->id) {
if(ts->stream->programs[k]->discard == AVDISCARD_ALL)
discarded++;
else
used++;
}
}
}
}
return !used && discarded;
}
/**
* Assemble PES packets out of TS packets, and then call the "section_cb"
* function when they are complete.
*/
static void write_section_data(AVFormatContext *s, MpegTSFilter *tss1,
const uint8_t *buf, int buf_size, int is_start)
{
MpegTSSectionFilter *tss = &tss1->u.section_filter;
int len;
if (is_start) {
memcpy(tss->section_buf, buf, buf_size);
tss->section_index = buf_size;
tss->section_h_size = -1;
tss->end_of_section_reached = 0;
} else {
if (tss->end_of_section_reached)
return;
len = 4096 - tss->section_index;
if (buf_size < len)
len = buf_size;
memcpy(tss->section_buf + tss->section_index, buf, len);
tss->section_index += len;
}
/* compute section length if possible */
if (tss->section_h_size == -1 && tss->section_index >= 3) {
len = (AV_RB16(tss->section_buf + 1) & 0xfff) + 3;
if (len > 4096)
return;
tss->section_h_size = len;
}
if (tss->section_h_size != -1 && tss->section_index >= tss->section_h_size) {
tss->end_of_section_reached = 1;
if (!tss->check_crc ||
av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1,
tss->section_buf, tss->section_h_size) == 0)
tss->section_cb(tss1, tss->section_buf, tss->section_h_size);
}
}
static MpegTSFilter *mpegts_open_section_filter(MpegTSContext *ts, unsigned int pid,
SectionCallback *section_cb, void *opaque,
int check_crc)
{
MpegTSFilter *filter;
MpegTSSectionFilter *sec;
av_dlog(ts->stream, "Filter: pid=0x%x\n", pid);
if (pid >= NB_PID_MAX || ts->pids[pid])
return NULL;
filter = av_mallocz(sizeof(MpegTSFilter));
if (!filter)
return NULL;
ts->pids[pid] = filter;
filter->type = MPEGTS_SECTION;
filter->pid = pid;
filter->last_cc = -1;
sec = &filter->u.section_filter;
sec->section_cb = section_cb;
sec->opaque = opaque;
sec->section_buf = av_malloc(MAX_SECTION_SIZE);
sec->check_crc = check_crc;
if (!sec->section_buf) {
av_free(filter);
return NULL;
}
return filter;
}
static MpegTSFilter *mpegts_open_pes_filter(MpegTSContext *ts, unsigned int pid,
PESCallback *pes_cb,
void *opaque)
{
MpegTSFilter *filter;
MpegTSPESFilter *pes;
if (pid >= NB_PID_MAX || ts->pids[pid])
return NULL;
filter = av_mallocz(sizeof(MpegTSFilter));
if (!filter)
return NULL;
ts->pids[pid] = filter;
filter->type = MPEGTS_PES;
filter->pid = pid;
filter->last_cc = -1;
pes = &filter->u.pes_filter;
pes->pes_cb = pes_cb;
pes->opaque = opaque;
return filter;
}
static void mpegts_close_filter(MpegTSContext *ts, MpegTSFilter *filter)
{
int pid;
pid = filter->pid;
if (filter->type == MPEGTS_SECTION)
av_freep(&filter->u.section_filter.section_buf);
else if (filter->type == MPEGTS_PES) {
PESContext *pes = filter->u.pes_filter.opaque;
av_freep(&pes->buffer);
/* referenced private data will be freed later in
* av_close_input_stream */
if (!((PESContext *)filter->u.pes_filter.opaque)->st) {
av_freep(&filter->u.pes_filter.opaque);
}
}
av_free(filter);
ts->pids[pid] = NULL;
}
static int analyze(const uint8_t *buf, int size, int packet_size, int *index){
int stat[TS_MAX_PACKET_SIZE];
int i;
int x=0;
int best_score=0;
memset(stat, 0, packet_size*sizeof(int));
for(x=i=0; i<size-3; i++){
if(buf[i] == 0x47 && !(buf[i+1] & 0x80) && (buf[i+3] & 0x30)){
stat[x]++;
if(stat[x] > best_score){
best_score= stat[x];
if(index) *index= x;
}
}
x++;
if(x == packet_size) x= 0;
}
return best_score;
}
/* autodetect fec presence. Must have at least 1024 bytes */
static int get_packet_size(const uint8_t *buf, int size)
{
int score, fec_score, dvhs_score;
if (size < (TS_FEC_PACKET_SIZE * 5 + 1))
return -1;
score = analyze(buf, size, TS_PACKET_SIZE, NULL);
dvhs_score = analyze(buf, size, TS_DVHS_PACKET_SIZE, NULL);
fec_score= analyze(buf, size, TS_FEC_PACKET_SIZE, NULL);
// av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
if (score > fec_score && score > dvhs_score) return TS_PACKET_SIZE;
else if(dvhs_score > score && dvhs_score > fec_score) return TS_DVHS_PACKET_SIZE;
else if(score < fec_score && dvhs_score < fec_score) return TS_FEC_PACKET_SIZE;
else return -1;
}
typedef struct SectionHeader {
uint8_t tid;
uint16_t id;
uint8_t version;
uint8_t sec_num;
uint8_t last_sec_num;
} SectionHeader;
static inline int get8(const uint8_t **pp, const uint8_t *p_end)
{
const uint8_t *p;
int c;
p = *pp;
if (p >= p_end)
return -1;
c = *p++;
*pp = p;
return c;
}
static inline int get16(const uint8_t **pp, const uint8_t *p_end)
{
const uint8_t *p;
int c;
p = *pp;
if ((p + 1) >= p_end)
return -1;
c = AV_RB16(p);
p += 2;
*pp = p;
return c;
}
/* read and allocate a DVB string preceeded by its length */
static char *getstr8(const uint8_t **pp, const uint8_t *p_end)
{
int len;
const uint8_t *p;
char *str;
p = *pp;
len = get8(&p, p_end);
if (len < 0)
return NULL;
if ((p + len) > p_end)
return NULL;
str = av_malloc(len + 1);
if (!str)
return NULL;
memcpy(str, p, len);
str[len] = '\0';
p += len;
*pp = p;
return str;
}
static int parse_section_header(SectionHeader *h,
const uint8_t **pp, const uint8_t *p_end)
{
int val;
val = get8(pp, p_end);
if (val < 0)
return -1;
h->tid = val;
*pp += 2;
val = get16(pp, p_end);
if (val < 0)
return -1;
h->id = val;
val = get8(pp, p_end);
if (val < 0)
return -1;
h->version = (val >> 1) & 0x1f;
val = get8(pp, p_end);
if (val < 0)
return -1;
h->sec_num = val;
val = get8(pp, p_end);
if (val < 0)
return -1;
h->last_sec_num = val;
return 0;
}
typedef struct {
uint32_t stream_type;
enum AVMediaType codec_type;
enum CodecID codec_id;
} StreamType;
static const StreamType ISO_types[] = {
{ 0x01, AVMEDIA_TYPE_VIDEO, CODEC_ID_MPEG2VIDEO },
{ 0x02, AVMEDIA_TYPE_VIDEO, CODEC_ID_MPEG2VIDEO },
{ 0x03, AVMEDIA_TYPE_AUDIO, CODEC_ID_MP3 },
{ 0x04, AVMEDIA_TYPE_AUDIO, CODEC_ID_MP3 },
{ 0x0f, AVMEDIA_TYPE_AUDIO, CODEC_ID_AAC },
{ 0x10, AVMEDIA_TYPE_VIDEO, CODEC_ID_MPEG4 },
{ 0x11, AVMEDIA_TYPE_AUDIO, CODEC_ID_AAC_LATM }, /* LATM syntax */
{ 0x1b, AVMEDIA_TYPE_VIDEO, CODEC_ID_H264 },
{ 0xd1, AVMEDIA_TYPE_VIDEO, CODEC_ID_DIRAC },
{ 0xea, AVMEDIA_TYPE_VIDEO, CODEC_ID_VC1 },
{ 0 },
};
static const StreamType HDMV_types[] = {
{ 0x80, AVMEDIA_TYPE_AUDIO, CODEC_ID_PCM_BLURAY },
{ 0x81, AVMEDIA_TYPE_AUDIO, CODEC_ID_AC3 },
{ 0x82, AVMEDIA_TYPE_AUDIO, CODEC_ID_DTS },
{ 0x83, AVMEDIA_TYPE_AUDIO, CODEC_ID_TRUEHD },
{ 0x84, AVMEDIA_TYPE_AUDIO, CODEC_ID_EAC3 },
{ 0x90, AVMEDIA_TYPE_SUBTITLE, CODEC_ID_HDMV_PGS_SUBTITLE },
{ 0 },
};
/* ATSC ? */
static const StreamType MISC_types[] = {
{ 0x81, AVMEDIA_TYPE_AUDIO, CODEC_ID_AC3 },
{ 0x8a, AVMEDIA_TYPE_AUDIO, CODEC_ID_DTS },
{ 0 },
};
static const StreamType REGD_types[] = {
{ MKTAG('d','r','a','c'), AVMEDIA_TYPE_VIDEO, CODEC_ID_DIRAC },
{ MKTAG('A','C','-','3'), AVMEDIA_TYPE_AUDIO, CODEC_ID_AC3 },
{ MKTAG('B','S','S','D'), AVMEDIA_TYPE_AUDIO, CODEC_ID_S302M },
{ 0 },
};
/* descriptor present */
static const StreamType DESC_types[] = {
{ 0x6a, AVMEDIA_TYPE_AUDIO, CODEC_ID_AC3 }, /* AC-3 descriptor */
{ 0x7a, AVMEDIA_TYPE_AUDIO, CODEC_ID_EAC3 }, /* E-AC-3 descriptor */
{ 0x7b, AVMEDIA_TYPE_AUDIO, CODEC_ID_DTS },
{ 0x56, AVMEDIA_TYPE_SUBTITLE, CODEC_ID_DVB_TELETEXT },
{ 0x59, AVMEDIA_TYPE_SUBTITLE, CODEC_ID_DVB_SUBTITLE }, /* subtitling descriptor */
{ 0 },
};
static void mpegts_find_stream_type(AVStream *st,
uint32_t stream_type, const StreamType *types)
{
for (; types->stream_type; types++) {
if (stream_type == types->stream_type) {
st->codec->codec_type = types->codec_type;
st->codec->codec_id = types->codec_id;
st->request_probe = 0;
return;
}
}
}
static int mpegts_set_stream_info(AVStream *st, PESContext *pes,
uint32_t stream_type, uint32_t prog_reg_desc)
{
av_set_pts_info(st, 33, 1, 90000);
st->priv_data = pes;
st->codec->codec_type = AVMEDIA_TYPE_DATA;
st->codec->codec_id = CODEC_ID_NONE;
st->need_parsing = AVSTREAM_PARSE_FULL;
pes->st = st;
pes->stream_type = stream_type;
av_log(pes->stream, AV_LOG_DEBUG,
"stream=%d stream_type=%x pid=%x prog_reg_desc=%.4s\n",
st->index, pes->stream_type, pes->pid, (char*)&prog_reg_desc);
st->codec->codec_tag = pes->stream_type;
mpegts_find_stream_type(st, pes->stream_type, ISO_types);
if (prog_reg_desc == AV_RL32("HDMV") &&
st->codec->codec_id == CODEC_ID_NONE) {
mpegts_find_stream_type(st, pes->stream_type, HDMV_types);
if (pes->stream_type == 0x83) {
// HDMV TrueHD streams also contain an AC3 coded version of the
// audio track - add a second stream for this
AVStream *sub_st;
// priv_data cannot be shared between streams
PESContext *sub_pes = av_malloc(sizeof(*sub_pes));
if (!sub_pes)
return AVERROR(ENOMEM);
memcpy(sub_pes, pes, sizeof(*sub_pes));
sub_st = av_new_stream(pes->stream, pes->pid);
if (!sub_st) {
av_free(sub_pes);
return AVERROR(ENOMEM);
}
av_set_pts_info(sub_st, 33, 1, 90000);
sub_st->priv_data = sub_pes;
sub_st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
sub_st->codec->codec_id = CODEC_ID_AC3;
sub_st->need_parsing = AVSTREAM_PARSE_FULL;
sub_pes->sub_st = pes->sub_st = sub_st;
}
}
if (st->codec->codec_id == CODEC_ID_NONE)
mpegts_find_stream_type(st, pes->stream_type, MISC_types);
return 0;
}
static void new_pes_packet(PESContext *pes, AVPacket *pkt)
{
av_init_packet(pkt);
pkt->destruct = av_destruct_packet;
pkt->data = pes->buffer;
pkt->size = pes->data_index;
memset(pkt->data+pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
// Separate out the AC3 substream from an HDMV combined TrueHD/AC3 PID
if (pes->sub_st && pes->stream_type == 0x83 && pes->extended_stream_id == 0x76)
pkt->stream_index = pes->sub_st->index;
else
pkt->stream_index = pes->st->index;
pkt->pts = pes->pts;
pkt->dts = pes->dts;
/* store position of first TS packet of this PES packet */
pkt->pos = pes->ts_packet_pos;
/* reset pts values */
pes->pts = AV_NOPTS_VALUE;
pes->dts = AV_NOPTS_VALUE;
pes->buffer = NULL;
pes->data_index = 0;
}
/* return non zero if a packet could be constructed */
static int mpegts_push_data(MpegTSFilter *filter,
const uint8_t *buf, int buf_size, int is_start,
int64_t pos)
{
PESContext *pes = filter->u.pes_filter.opaque;
MpegTSContext *ts = pes->ts;
const uint8_t *p;
int len, code;
if(!ts->pkt)
return 0;
if (is_start) {
if (pes->state == MPEGTS_PAYLOAD && pes->data_index > 0) {
new_pes_packet(pes, ts->pkt);
ts->stop_parse = 1;
}
pes->state = MPEGTS_HEADER;
pes->data_index = 0;
pes->ts_packet_pos = pos;
}
p = buf;
while (buf_size > 0) {
switch(pes->state) {
case MPEGTS_HEADER:
len = PES_START_SIZE - pes->data_index;
if (len > buf_size)
len = buf_size;
memcpy(pes->header + pes->data_index, p, len);
pes->data_index += len;
p += len;
buf_size -= len;
if (pes->data_index == PES_START_SIZE) {
/* we got all the PES or section header. We can now
decide */
if (pes->header[0] == 0x00 && pes->header[1] == 0x00 &&
pes->header[2] == 0x01) {
/* it must be an mpeg2 PES stream */
code = pes->header[3] | 0x100;
av_dlog(pes->stream, "pid=%x pes_code=%#x\n", pes->pid, code);
if ((pes->st && pes->st->discard == AVDISCARD_ALL) ||
code == 0x1be) /* padding_stream */
goto skip;
/* stream not present in PMT */
if (!pes->st) {
pes->st = av_new_stream(ts->stream, pes->pid);
if (!pes->st)
return AVERROR(ENOMEM);
mpegts_set_stream_info(pes->st, pes, 0, 0);
}
pes->total_size = AV_RB16(pes->header + 4);
/* NOTE: a zero total size means the PES size is
unbounded */
if (!pes->total_size)
pes->total_size = MAX_PES_PAYLOAD;
/* allocate pes buffer */
pes->buffer = av_malloc(pes->total_size+FF_INPUT_BUFFER_PADDING_SIZE);
if (!pes->buffer)
return AVERROR(ENOMEM);
if (code != 0x1bc && code != 0x1bf && /* program_stream_map, private_stream_2 */
code != 0x1f0 && code != 0x1f1 && /* ECM, EMM */
code != 0x1ff && code != 0x1f2 && /* program_stream_directory, DSMCC_stream */
code != 0x1f8) { /* ITU-T Rec. H.222.1 type E stream */
pes->state = MPEGTS_PESHEADER;
if (pes->st->codec->codec_id == CODEC_ID_NONE && !pes->st->request_probe) {
av_dlog(pes->stream, "pid=%x stream_type=%x probing\n",
pes->pid, pes->stream_type);
pes->st->request_probe= 1;
}
} else {
pes->state = MPEGTS_PAYLOAD;
pes->data_index = 0;
}
} else {
/* otherwise, it should be a table */
/* skip packet */
skip:
pes->state = MPEGTS_SKIP;
continue;
}
}
break;
/**********************************************/
/* PES packing parsing */
case MPEGTS_PESHEADER:
len = PES_HEADER_SIZE - pes->data_index;
if (len < 0)
return -1;
if (len > buf_size)
len = buf_size;
memcpy(pes->header + pes->data_index, p, len);
pes->data_index += len;
p += len;
buf_size -= len;
if (pes->data_index == PES_HEADER_SIZE) {
pes->pes_header_size = pes->header[8] + 9;
pes->state = MPEGTS_PESHEADER_FILL;
}
break;
case MPEGTS_PESHEADER_FILL:
len = pes->pes_header_size - pes->data_index;
if (len < 0)
return -1;
if (len > buf_size)
len = buf_size;
memcpy(pes->header + pes->data_index, p, len);
pes->data_index += len;
p += len;
buf_size -= len;
if (pes->data_index == pes->pes_header_size) {
const uint8_t *r;
unsigned int flags, pes_ext, skip;
flags = pes->header[7];
r = pes->header + 9;
pes->pts = AV_NOPTS_VALUE;
pes->dts = AV_NOPTS_VALUE;
if ((flags & 0xc0) == 0x80) {
pes->dts = pes->pts = ff_parse_pes_pts(r);
r += 5;
} else if ((flags & 0xc0) == 0xc0) {
pes->pts = ff_parse_pes_pts(r);
r += 5;
pes->dts = ff_parse_pes_pts(r);
r += 5;
}
pes->extended_stream_id = -1;
if (flags & 0x01) { /* PES extension */
pes_ext = *r++;
/* Skip PES private data, program packet sequence counter and P-STD buffer */
skip = (pes_ext >> 4) & 0xb;
skip += skip & 0x9;
r += skip;
if ((pes_ext & 0x41) == 0x01 &&
(r + 2) <= (pes->header + pes->pes_header_size)) {
/* PES extension 2 */
if ((r[0] & 0x7f) > 0 && (r[1] & 0x80) == 0)
pes->extended_stream_id = r[1];
}
}
/* we got the full header. We parse it and get the payload */
pes->state = MPEGTS_PAYLOAD;
pes->data_index = 0;
}
break;
case MPEGTS_PAYLOAD:
if (buf_size > 0 && pes->buffer) {
if (pes->data_index > 0 && pes->data_index+buf_size > pes->total_size) {
new_pes_packet(pes, ts->pkt);
pes->total_size = MAX_PES_PAYLOAD;
pes->buffer = av_malloc(pes->total_size+FF_INPUT_BUFFER_PADDING_SIZE);
if (!pes->buffer)
return AVERROR(ENOMEM);
ts->stop_parse = 1;
} else if (pes->data_index == 0 && buf_size > pes->total_size) {
// pes packet size is < ts size packet and pes data is padded with 0xff
// not sure if this is legal in ts but see issue #2392
buf_size = pes->total_size;
}
memcpy(pes->buffer+pes->data_index, p, buf_size);
pes->data_index += buf_size;
}
buf_size = 0;
/* emit complete packets with known packet size
* decreases demuxer delay for infrequent packets like subtitles from
* a couple of seconds to milliseconds for properly muxed files.
* total_size is the number of bytes following pes_packet_length
* in the pes header, i.e. not counting the first 6 bytes */
if (!ts->stop_parse && pes->total_size < MAX_PES_PAYLOAD &&
pes->pes_header_size + pes->data_index == pes->total_size + 6) {
ts->stop_parse = 1;
new_pes_packet(pes, ts->pkt);
}
break;
case MPEGTS_SKIP:
buf_size = 0;
break;
}
}
return 0;
}
static PESContext *add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid)
{
MpegTSFilter *tss;
PESContext *pes;
/* if no pid found, then add a pid context */
pes = av_mallocz(sizeof(PESContext));
if (!pes)
return 0;
pes->ts = ts;
pes->stream = ts->stream;
pes->pid = pid;
pes->pcr_pid = pcr_pid;
pes->state = MPEGTS_SKIP;
pes->pts = AV_NOPTS_VALUE;
pes->dts = AV_NOPTS_VALUE;
tss = mpegts_open_pes_filter(ts, pid, mpegts_push_data, pes);
if (!tss) {
av_free(pes);
return 0;
}
return pes;
}
static int mp4_read_iods(AVFormatContext *s, const uint8_t *buf, unsigned size,
int *es_id, uint8_t **dec_config_descr,
int *dec_config_descr_size)
{
AVIOContext pb;
int tag;
unsigned len;
ffio_init_context(&pb, buf, size, 0, NULL, NULL, NULL, NULL);
len = ff_mp4_read_descr(s, &pb, &tag);
if (tag == MP4IODescrTag) {
avio_rb16(&pb); // ID
avio_r8(&pb);
avio_r8(&pb);
avio_r8(&pb);
avio_r8(&pb);
avio_r8(&pb);
len = ff_mp4_read_descr(s, &pb, &tag);
if (tag == MP4ESDescrTag) {
*es_id = avio_rb16(&pb); /* ES_ID */
av_dlog(s, "ES_ID %#x\n", *es_id);
avio_r8(&pb); /* priority */
len = ff_mp4_read_descr(s, &pb, &tag);
if (tag == MP4DecConfigDescrTag) {
*dec_config_descr = av_malloc(len);
if (!*dec_config_descr)
return AVERROR(ENOMEM);
*dec_config_descr_size = len;
avio_read(&pb, *dec_config_descr, len);
}
}
}
return 0;
}
int ff_parse_mpeg2_descriptor(AVFormatContext *fc, AVStream *st, int stream_type,
const uint8_t **pp, const uint8_t *desc_list_end,
int mp4_dec_config_descr_len, int mp4_es_id, int pid,
uint8_t *mp4_dec_config_descr)
{
const uint8_t *desc_end;
int desc_len, desc_tag;
char language[252];
int i;
desc_tag = get8(pp, desc_list_end);
if (desc_tag < 0)
return -1;
desc_len = get8(pp, desc_list_end);
if (desc_len < 0)
return -1;
desc_end = *pp + desc_len;
if (desc_end > desc_list_end)
return -1;
av_dlog(fc, "tag: 0x%02x len=%d\n", desc_tag, desc_len);
if (st->codec->codec_id == CODEC_ID_NONE &&
stream_type == STREAM_TYPE_PRIVATE_DATA)
mpegts_find_stream_type(st, desc_tag, DESC_types);
switch(desc_tag) {
case 0x1F: /* FMC descriptor */
get16(pp, desc_end);
if (st->codec->codec_id == CODEC_ID_AAC_LATM &&
mp4_dec_config_descr_len && mp4_es_id == pid) {
AVIOContext pb;
ffio_init_context(&pb, mp4_dec_config_descr,
mp4_dec_config_descr_len, 0, NULL, NULL, NULL, NULL);
ff_mp4_read_dec_config_descr(fc, st, &pb);
if (st->codec->codec_id == CODEC_ID_AAC &&
st->codec->extradata_size > 0)
st->need_parsing = 0;
}
break;
case 0x56: /* DVB teletext descriptor */
language[0] = get8(pp, desc_end);
language[1] = get8(pp, desc_end);
language[2] = get8(pp, desc_end);
language[3] = 0;
av_dict_set(&st->metadata, "language", language, 0);
break;
case 0x59: /* subtitling descriptor */
language[0] = get8(pp, desc_end);
language[1] = get8(pp, desc_end);
language[2] = get8(pp, desc_end);
language[3] = 0;
/* hearing impaired subtitles detection */
switch(get8(pp, desc_end)) {
case 0x20: /* DVB subtitles (for the hard of hearing) with no monitor aspect ratio criticality */
case 0x21: /* DVB subtitles (for the hard of hearing) for display on 4:3 aspect ratio monitor */
case 0x22: /* DVB subtitles (for the hard of hearing) for display on 16:9 aspect ratio monitor */
case 0x23: /* DVB subtitles (for the hard of hearing) for display on 2.21:1 aspect ratio monitor */
case 0x24: /* DVB subtitles (for the hard of hearing) for display on a high definition monitor */
case 0x25: /* DVB subtitles (for the hard of hearing) with plano-stereoscopic disparity for display on a high definition monitor */
st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
break;
}
if (st->codec->extradata) {
if (st->codec->extradata_size == 4 && memcmp(st->codec->extradata, *pp, 4))
av_log_ask_for_sample(fc, "DVB sub with multiple IDs\n");
} else {
st->codec->extradata = av_malloc(4 + FF_INPUT_BUFFER_PADDING_SIZE);
if (st->codec->extradata) {
st->codec->extradata_size = 4;
memcpy(st->codec->extradata, *pp, 4);
}
}
*pp += 4;
av_dict_set(&st->metadata, "language", language, 0);
break;
case 0x0a: /* ISO 639 language descriptor */
for (i = 0; i + 4 <= desc_len; i += 4) {
language[i + 0] = get8(pp, desc_end);
language[i + 1] = get8(pp, desc_end);
language[i + 2] = get8(pp, desc_end);
language[i + 3] = ',';
switch (get8(pp, desc_end)) {
case 0x01: st->disposition |= AV_DISPOSITION_CLEAN_EFFECTS; break;
case 0x02: st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED; break;
case 0x03: st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED; break;
}
}
if (i) {
language[i - 1] = 0;
av_dict_set(&st->metadata, "language", language, 0);
}
break;
case 0x05: /* registration descriptor */
st->codec->codec_tag = bytestream_get_le32(pp);
av_dlog(fc, "reg_desc=%.4s\n", (char*)&st->codec->codec_tag);
if (st->codec->codec_id == CODEC_ID_NONE &&
stream_type == STREAM_TYPE_PRIVATE_DATA)
mpegts_find_stream_type(st, st->codec->codec_tag, REGD_types);
break;
case 0x52: /* stream identifier descriptor */
st->stream_identifier = 1 + get8(pp, desc_end);
break;
default:
break;
}
*pp = desc_end;
return 0;
}
static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
{
MpegTSContext *ts = filter->u.section_filter.opaque;
SectionHeader h1, *h = &h1;
PESContext *pes;
AVStream *st;
const uint8_t *p, *p_end, *desc_list_end;
int program_info_length, pcr_pid, pid, stream_type;
int desc_list_len;
uint32_t prog_reg_desc = 0; /* registration descriptor */
uint8_t *mp4_dec_config_descr = NULL;
int mp4_dec_config_descr_len = 0;
int mp4_es_id = 0;
av_dlog(ts->stream, "PMT: len %i\n", section_len);
hex_dump_debug(ts->stream, (uint8_t *)section, section_len);
p_end = section + section_len - 4;
p = section;
if (parse_section_header(h, &p, p_end) < 0)
return;
av_dlog(ts->stream, "sid=0x%x sec_num=%d/%d\n",
h->id, h->sec_num, h->last_sec_num);
if (h->tid != PMT_TID)
return;
clear_program(ts, h->id);
pcr_pid = get16(&p, p_end) & 0x1fff;
if (pcr_pid < 0)
return;
add_pid_to_pmt(ts, h->id, pcr_pid);
set_pcr_pid(ts->stream, h->id, pcr_pid);
av_dlog(ts->stream, "pcr_pid=0x%x\n", pcr_pid);
program_info_length = get16(&p, p_end) & 0xfff;
if (program_info_length < 0)
return;
while(program_info_length >= 2) {
uint8_t tag, len;
tag = get8(&p, p_end);
len = get8(&p, p_end);
av_dlog(ts->stream, "program tag: 0x%02x len=%d\n", tag, len);
if(len > program_info_length - 2)
//something else is broken, exit the program_descriptors_loop
break;
program_info_length -= len + 2;
if (tag == 0x1d) { // IOD descriptor
get8(&p, p_end); // scope
get8(&p, p_end); // label
len -= 2;
mp4_read_iods(ts->stream, p, len, &mp4_es_id,
&mp4_dec_config_descr, &mp4_dec_config_descr_len);
} else if (tag == 0x05 && len >= 4) { // registration descriptor
prog_reg_desc = bytestream_get_le32(&p);
len -= 4;
}
p += len;
}
p += program_info_length;
if (p >= p_end)
goto out;
// stop parsing after pmt, we found header
if (!ts->stream->nb_streams)
ts->stop_parse = 1;
for(;;) {
st = 0;
stream_type = get8(&p, p_end);
if (stream_type < 0)
break;
pid = get16(&p, p_end) & 0x1fff;
if (pid < 0)
break;
/* now create ffmpeg stream */
if (ts->pids[pid] && ts->pids[pid]->type == MPEGTS_PES) {
pes = ts->pids[pid]->u.pes_filter.opaque;
if (!pes->st)
pes->st = av_new_stream(pes->stream, pes->pid);
st = pes->st;
} else {
if (ts->pids[pid]) mpegts_close_filter(ts, ts->pids[pid]); //wrongly added sdt filter probably
pes = add_pes_stream(ts, pid, pcr_pid);
if (pes)
st = av_new_stream(pes->stream, pes->pid);
}
if (!st)
goto out;
if (!pes->stream_type)
mpegts_set_stream_info(st, pes, stream_type, prog_reg_desc);
add_pid_to_pmt(ts, h->id, pid);
ff_program_add_stream_index(ts->stream, h->id, st->index);
desc_list_len = get16(&p, p_end) & 0xfff;
if (desc_list_len < 0)
break;
desc_list_end = p + desc_list_len;
if (desc_list_end > p_end)
break;
for(;;) {
if (ff_parse_mpeg2_descriptor(ts->stream, st, stream_type, &p, desc_list_end,
mp4_dec_config_descr_len, mp4_es_id, pid, mp4_dec_config_descr) < 0)
break;
if (prog_reg_desc == AV_RL32("HDMV") && stream_type == 0x83 && pes->sub_st) {
ff_program_add_stream_index(ts->stream, h->id, pes->sub_st->index);
pes->sub_st->codec->codec_tag = st->codec->codec_tag;
}
}
p = desc_list_end;
}
out:
av_free(mp4_dec_config_descr);
}
static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
{
MpegTSContext *ts = filter->u.section_filter.opaque;
SectionHeader h1, *h = &h1;
const uint8_t *p, *p_end;
int sid, pmt_pid;
AVProgram *program;
av_dlog(ts->stream, "PAT:\n");
hex_dump_debug(ts->stream, (uint8_t *)section, section_len);
p_end = section + section_len - 4;
p = section;
if (parse_section_header(h, &p, p_end) < 0)
return;
if (h->tid != PAT_TID)
return;
ts->stream->ts_id = h->id;
clear_programs(ts);
for(;;) {
sid = get16(&p, p_end);
if (sid < 0)
break;
pmt_pid = get16(&p, p_end) & 0x1fff;
if (pmt_pid < 0)
break;
av_dlog(ts->stream, "sid=0x%x pid=0x%x\n", sid, pmt_pid);
if (sid == 0x0000) {
/* NIT info */
} else {
program = av_new_program(ts->stream, sid);
program->program_num = sid;
program->pmt_pid = pmt_pid;
if (ts->pids[pmt_pid])
mpegts_close_filter(ts, ts->pids[pmt_pid]);
mpegts_open_section_filter(ts, pmt_pid, pmt_cb, ts, 1);
add_pat_entry(ts, sid);
add_pid_to_pmt(ts, sid, 0); //add pat pid to program
add_pid_to_pmt(ts, sid, pmt_pid);
}
}
}
static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
{
MpegTSContext *ts = filter->u.section_filter.opaque;
SectionHeader h1, *h = &h1;
const uint8_t *p, *p_end, *desc_list_end, *desc_end;
int onid, val, sid, desc_list_len, desc_tag, desc_len, service_type;
char *name, *provider_name;
av_dlog(ts->stream, "SDT:\n");
hex_dump_debug(ts->stream, (uint8_t *)section, section_len);
p_end = section + section_len - 4;
p = section;
if (parse_section_header(h, &p, p_end) < 0)
return;
if (h->tid != SDT_TID)
return;
onid = get16(&p, p_end);
if (onid < 0)
return;
val = get8(&p, p_end);
if (val < 0)
return;
for(;;) {
sid = get16(&p, p_end);
if (sid < 0)
break;
val = get8(&p, p_end);
if (val < 0)
break;
desc_list_len = get16(&p, p_end) & 0xfff;
if (desc_list_len < 0)
break;
desc_list_end = p + desc_list_len;
if (desc_list_end > p_end)
break;
for(;;) {
desc_tag = get8(&p, desc_list_end);
if (desc_tag < 0)
break;
desc_len = get8(&p, desc_list_end);
desc_end = p + desc_len;
if (desc_end > desc_list_end)
break;
av_dlog(ts->stream, "tag: 0x%02x len=%d\n",
desc_tag, desc_len);
switch(desc_tag) {
case 0x48:
service_type = get8(&p, p_end);
if (service_type < 0)
break;
provider_name = getstr8(&p, p_end);
if (!provider_name)
break;
name = getstr8(&p, p_end);
if (name) {
AVProgram *program = av_new_program(ts->stream, sid);
if(program) {
av_dict_set(&program->metadata, "service_name", name, 0);
av_dict_set(&program->metadata, "service_provider", provider_name, 0);
}
}
av_free(name);
av_free(provider_name);
break;
default:
break;
}
p = desc_end;
}
p = desc_list_end;
}
}
/* handle one TS packet */
static int handle_packet(MpegTSContext *ts, const uint8_t *packet)
{
AVFormatContext *s = ts->stream;
MpegTSFilter *tss;
int len, pid, cc, cc_ok, afc, is_start;
const uint8_t *p, *p_end;
int64_t pos;
pid = AV_RB16(packet + 1) & 0x1fff;
if(pid && discard_pid(ts, pid))
return 0;
is_start = packet[1] & 0x40;
tss = ts->pids[pid];
if (ts->auto_guess && tss == NULL && is_start) {
add_pes_stream(ts, pid, -1);
tss = ts->pids[pid];
}
if (!tss)
return 0;
/* continuity check (currently not used) */
cc = (packet[3] & 0xf);
cc_ok = (tss->last_cc < 0) || ((((tss->last_cc + 1) & 0x0f) == cc));
tss->last_cc = cc;
/* skip adaptation field */
afc = (packet[3] >> 4) & 3;
p = packet + 4;
if (afc == 0) /* reserved value */
return 0;
if (afc == 2) /* adaptation field only */
return 0;
if (afc == 3) {
/* skip adapation field */
p += p[0] + 1;
}
/* if past the end of packet, ignore */
p_end = packet + TS_PACKET_SIZE;
if (p >= p_end)
return 0;
pos = avio_tell(ts->stream->pb);
ts->pos47= pos % ts->raw_packet_size;
if (tss->type == MPEGTS_SECTION) {
if (is_start) {
/* pointer field present */
len = *p++;
if (p + len > p_end)
return 0;
if (len && cc_ok) {
/* write remaining section bytes */
write_section_data(s, tss,
p, len, 0);
/* check whether filter has been closed */
if (!ts->pids[pid])
return 0;
}
p += len;
if (p < p_end) {
write_section_data(s, tss,
p, p_end - p, 1);
}
} else {
if (cc_ok) {
write_section_data(s, tss,
p, p_end - p, 0);
}
}
} else {
int ret;
// Note: The position here points actually behind the current packet.
if ((ret = tss->u.pes_filter.pes_cb(tss, p, p_end - p, is_start,
pos - ts->raw_packet_size)) < 0)
return ret;
}
return 0;
}
/* XXX: try to find a better synchro over several packets (use
get_packet_size() ?) */
static int mpegts_resync(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
int c, i;
for(i = 0;i < MAX_RESYNC_SIZE; i++) {
c = avio_r8(pb);
if (url_feof(pb))
return -1;
if (c == 0x47) {
avio_seek(pb, -1, SEEK_CUR);
return 0;
}
}
av_log(s, AV_LOG_ERROR, "max resync size reached, could not find sync byte\n");
/* no sync found */
return -1;
}
/* return -1 if error or EOF. Return 0 if OK. */
static int read_packet(AVFormatContext *s, uint8_t *buf, int raw_packet_size)
{
AVIOContext *pb = s->pb;
int skip, len;
for(;;) {
len = avio_read(pb, buf, TS_PACKET_SIZE);
if (len != TS_PACKET_SIZE)
return len < 0 ? len : AVERROR_EOF;
/* check paquet sync byte */
if (buf[0] != 0x47) {
/* find a new packet start */
avio_seek(pb, -TS_PACKET_SIZE, SEEK_CUR);
if (mpegts_resync(s) < 0)
return AVERROR(EAGAIN);
else
continue;
} else {
skip = raw_packet_size - TS_PACKET_SIZE;
if (skip > 0)
avio_skip(pb, skip);
break;
}
}
return 0;
}
static int handle_packets(MpegTSContext *ts, int nb_packets)
{
AVFormatContext *s = ts->stream;
uint8_t packet[TS_PACKET_SIZE];
int packet_num, ret;
ts->stop_parse = 0;
packet_num = 0;
for(;;) {
if (ts->stop_parse>0)
break;
packet_num++;
if (nb_packets != 0 && packet_num >= nb_packets)
break;
ret = read_packet(s, packet, ts->raw_packet_size);
if (ret != 0)
return ret;
ret = handle_packet(ts, packet);
if (ret != 0)
return ret;
}
return 0;
}
static int mpegts_probe(AVProbeData *p)
{
#if 1
const int size= p->buf_size;
int score, fec_score, dvhs_score;
int check_count= size / TS_FEC_PACKET_SIZE;
#define CHECK_COUNT 10
if (check_count < CHECK_COUNT)
return -1;
score = analyze(p->buf, TS_PACKET_SIZE *check_count, TS_PACKET_SIZE , NULL)*CHECK_COUNT/check_count;
dvhs_score= analyze(p->buf, TS_DVHS_PACKET_SIZE*check_count, TS_DVHS_PACKET_SIZE, NULL)*CHECK_COUNT/check_count;
fec_score = analyze(p->buf, TS_FEC_PACKET_SIZE *check_count, TS_FEC_PACKET_SIZE , NULL)*CHECK_COUNT/check_count;
// av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
// we need a clear definition for the returned score otherwise things will become messy sooner or later
if (score > fec_score && score > dvhs_score && score > 6) return AVPROBE_SCORE_MAX + score - CHECK_COUNT;
else if(dvhs_score > score && dvhs_score > fec_score && dvhs_score > 6) return AVPROBE_SCORE_MAX + dvhs_score - CHECK_COUNT;
else if( fec_score > 6) return AVPROBE_SCORE_MAX + fec_score - CHECK_COUNT;
else return -1;
#else
/* only use the extension for safer guess */
if (av_match_ext(p->filename, "ts"))
return AVPROBE_SCORE_MAX;
else
return 0;
#endif
}
/* return the 90kHz PCR and the extension for the 27MHz PCR. return
(-1) if not available */
static int parse_pcr(int64_t *ppcr_high, int *ppcr_low,
const uint8_t *packet)
{
int afc, len, flags;
const uint8_t *p;
unsigned int v;
afc = (packet[3] >> 4) & 3;
if (afc <= 1)
return -1;
p = packet + 4;
len = p[0];
p++;
if (len == 0)
return -1;
flags = *p++;
len--;
if (!(flags & 0x10))
return -1;
if (len < 6)
return -1;
v = AV_RB32(p);
*ppcr_high = ((int64_t)v << 1) | (p[4] >> 7);
*ppcr_low = ((p[4] & 1) << 8) | p[5];
return 0;
}
static int mpegts_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
MpegTSContext *ts = s->priv_data;
AVIOContext *pb = s->pb;
uint8_t buf[8*1024];
int len;
int64_t pos;
#if FF_API_FORMAT_PARAMETERS
if (ap) {
if (ap->mpeg2ts_compute_pcr)
ts->mpeg2ts_compute_pcr = ap->mpeg2ts_compute_pcr;
if(ap->mpeg2ts_raw){
av_log(s, AV_LOG_ERROR, "use mpegtsraw_demuxer!\n");
return -1;
}
}
#endif
/* read the first 1024 bytes to get packet size */
pos = avio_tell(pb);
len = avio_read(pb, buf, sizeof(buf));
if (len != sizeof(buf))
goto fail;
ts->raw_packet_size = get_packet_size(buf, sizeof(buf));
if (ts->raw_packet_size <= 0) {
av_log(s, AV_LOG_WARNING, "Could not detect TS packet size, defaulting to non-FEC/DVHS\n");
ts->raw_packet_size = TS_PACKET_SIZE;
}
ts->stream = s;
ts->auto_guess = 0;
if (s->iformat == &ff_mpegts_demuxer) {
/* normal demux */
/* first do a scaning to get all the services */
if (avio_seek(pb, pos, SEEK_SET) < 0)
av_log(s, AV_LOG_ERROR, "Unable to seek back to the start\n");
mpegts_open_section_filter(ts, SDT_PID, sdt_cb, ts, 1);
mpegts_open_section_filter(ts, PAT_PID, pat_cb, ts, 1);
handle_packets(ts, s->probesize / ts->raw_packet_size);
/* if could not find service, enable auto_guess */
ts->auto_guess = 1;
av_dlog(ts->stream, "tuning done\n");
s->ctx_flags |= AVFMTCTX_NOHEADER;
} else {
AVStream *st;
int pcr_pid, pid, nb_packets, nb_pcrs, ret, pcr_l;
int64_t pcrs[2], pcr_h;
int packet_count[2];
uint8_t packet[TS_PACKET_SIZE];
/* only read packets */
st = av_new_stream(s, 0);
if (!st)
goto fail;
av_set_pts_info(st, 60, 1, 27000000);
st->codec->codec_type = AVMEDIA_TYPE_DATA;
st->codec->codec_id = CODEC_ID_MPEG2TS;
/* we iterate until we find two PCRs to estimate the bitrate */
pcr_pid = -1;
nb_pcrs = 0;
nb_packets = 0;
for(;;) {
ret = read_packet(s, packet, ts->raw_packet_size);
if (ret < 0)
return -1;
pid = AV_RB16(packet + 1) & 0x1fff;
if ((pcr_pid == -1 || pcr_pid == pid) &&
parse_pcr(&pcr_h, &pcr_l, packet) == 0) {
pcr_pid = pid;
packet_count[nb_pcrs] = nb_packets;
pcrs[nb_pcrs] = pcr_h * 300 + pcr_l;
nb_pcrs++;
if (nb_pcrs >= 2)
break;
}
nb_packets++;
}
/* NOTE1: the bitrate is computed without the FEC */
/* NOTE2: it is only the bitrate of the start of the stream */
ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] - packet_count[0]);
ts->cur_pcr = pcrs[0] - ts->pcr_incr * packet_count[0];
s->bit_rate = (TS_PACKET_SIZE * 8) * 27e6 / ts->pcr_incr;
st->codec->bit_rate = s->bit_rate;
st->start_time = ts->cur_pcr;
av_dlog(ts->stream, "start=%0.3f pcr=%0.3f incr=%d\n",
st->start_time / 1000000.0, pcrs[0] / 27e6, ts->pcr_incr);
}
avio_seek(pb, pos, SEEK_SET);
return 0;
fail:
return -1;
}
#define MAX_PACKET_READAHEAD ((128 * 1024) / 188)
static int mpegts_raw_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
MpegTSContext *ts = s->priv_data;
int ret, i;
int64_t pcr_h, next_pcr_h, pos;
int pcr_l, next_pcr_l;
uint8_t pcr_buf[12];
if (av_new_packet(pkt, TS_PACKET_SIZE) < 0)
return AVERROR(ENOMEM);
pkt->pos= avio_tell(s->pb);
ret = read_packet(s, pkt->data, ts->raw_packet_size);
if (ret < 0) {
av_free_packet(pkt);
return ret;
}
if (ts->mpeg2ts_compute_pcr) {
/* compute exact PCR for each packet */
if (parse_pcr(&pcr_h, &pcr_l, pkt->data) == 0) {
/* we read the next PCR (XXX: optimize it by using a bigger buffer */
pos = avio_tell(s->pb);
for(i = 0; i < MAX_PACKET_READAHEAD; i++) {
avio_seek(s->pb, pos + i * ts->raw_packet_size, SEEK_SET);
avio_read(s->pb, pcr_buf, 12);
if (parse_pcr(&next_pcr_h, &next_pcr_l, pcr_buf) == 0) {
/* XXX: not precise enough */
ts->pcr_incr = ((next_pcr_h - pcr_h) * 300 + (next_pcr_l - pcr_l)) /
(i + 1);
break;
}
}
avio_seek(s->pb, pos, SEEK_SET);
/* no next PCR found: we use previous increment */
ts->cur_pcr = pcr_h * 300 + pcr_l;
}
pkt->pts = ts->cur_pcr;
pkt->duration = ts->pcr_incr;
ts->cur_pcr += ts->pcr_incr;
}
pkt->stream_index = 0;
return 0;
}
static int mpegts_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
MpegTSContext *ts = s->priv_data;
int ret, i;
if (avio_tell(s->pb) != ts->last_pos) {
/* seek detected, flush pes buffer */
for (i = 0; i < NB_PID_MAX; i++) {
if (ts->pids[i] && ts->pids[i]->type == MPEGTS_PES) {
PESContext *pes = ts->pids[i]->u.pes_filter.opaque;
av_freep(&pes->buffer);
pes->data_index = 0;
pes->state = MPEGTS_SKIP; /* skip until pes header */
}
}
}
ts->pkt = pkt;
ret = handle_packets(ts, 0);
if (ret < 0) {
/* flush pes data left */
for (i = 0; i < NB_PID_MAX; i++) {
if (ts->pids[i] && ts->pids[i]->type == MPEGTS_PES) {
PESContext *pes = ts->pids[i]->u.pes_filter.opaque;
if (pes->state == MPEGTS_PAYLOAD && pes->data_index > 0) {
new_pes_packet(pes, pkt);
pes->state = MPEGTS_SKIP;
ret = 0;
break;
}
}
}
}
ts->last_pos = avio_tell(s->pb);
return ret;
}
static int mpegts_read_close(AVFormatContext *s)
{
MpegTSContext *ts = s->priv_data;
int i;
clear_programs(ts);
for(i=0;i<NB_PID_MAX;i++)
if (ts->pids[i]) mpegts_close_filter(ts, ts->pids[i]);
return 0;
}
static int64_t mpegts_get_pcr(AVFormatContext *s, int stream_index,
int64_t *ppos, int64_t pos_limit)
{
MpegTSContext *ts = s->priv_data;
int64_t pos, timestamp;
uint8_t buf[TS_PACKET_SIZE];
int pcr_l, pcr_pid = ((PESContext*)s->streams[stream_index]->priv_data)->pcr_pid;
const int find_next= 1;
pos = ((*ppos + ts->raw_packet_size - 1 - ts->pos47) / ts->raw_packet_size) * ts->raw_packet_size + ts->pos47;
if (find_next) {
for(;;) {
avio_seek(s->pb, pos, SEEK_SET);
if (avio_read(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
return AV_NOPTS_VALUE;
if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
parse_pcr(&timestamp, &pcr_l, buf) == 0) {
break;
}
pos += ts->raw_packet_size;
}
} else {
for(;;) {
pos -= ts->raw_packet_size;
if (pos < 0)
return AV_NOPTS_VALUE;
avio_seek(s->pb, pos, SEEK_SET);
if (avio_read(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
return AV_NOPTS_VALUE;
if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
parse_pcr(&timestamp, &pcr_l, buf) == 0) {
break;
}
}
}
*ppos = pos;
return timestamp;
}
#ifdef USE_SYNCPOINT_SEARCH
static int read_seek2(AVFormatContext *s,
int stream_index,
int64_t min_ts,
int64_t target_ts,
int64_t max_ts,
int flags)
{
int64_t pos;
int64_t ts_ret, ts_adj;
int stream_index_gen_search;
AVStream *st;
AVParserState *backup;
backup = ff_store_parser_state(s);
// detect direction of seeking for search purposes
flags |= (target_ts - min_ts > (uint64_t)(max_ts - target_ts)) ?
AVSEEK_FLAG_BACKWARD : 0;
if (flags & AVSEEK_FLAG_BYTE) {
// use position directly, we will search starting from it
pos = target_ts;
} else {
// search for some position with good timestamp match
if (stream_index < 0) {
stream_index_gen_search = av_find_default_stream_index(s);
if (stream_index_gen_search < 0) {
ff_restore_parser_state(s, backup);
return -1;
}
st = s->streams[stream_index_gen_search];
// timestamp for default must be expressed in AV_TIME_BASE units
ts_adj = av_rescale(target_ts,
st->time_base.den,
AV_TIME_BASE * (int64_t)st->time_base.num);
} else {
ts_adj = target_ts;
stream_index_gen_search = stream_index;
}
pos = av_gen_search(s, stream_index_gen_search, ts_adj,
0, INT64_MAX, -1,
AV_NOPTS_VALUE,
AV_NOPTS_VALUE,
flags, &ts_ret, mpegts_get_pcr);
if (pos < 0) {
ff_restore_parser_state(s, backup);
return -1;
}
}
// search for actual matching keyframe/starting position for all streams
if (ff_gen_syncpoint_search(s, stream_index, pos,
min_ts, target_ts, max_ts,
flags) < 0) {
ff_restore_parser_state(s, backup);
return -1;
}
ff_free_parser_state(s, backup);
return 0;
}
static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags)
{
int ret;
if (flags & AVSEEK_FLAG_BACKWARD) {
flags &= ~AVSEEK_FLAG_BACKWARD;
ret = read_seek2(s, stream_index, INT64_MIN, target_ts, target_ts, flags);
if (ret < 0)
// for compatibility reasons, seek to the best-fitting timestamp
ret = read_seek2(s, stream_index, INT64_MIN, target_ts, INT64_MAX, flags);
} else {
ret = read_seek2(s, stream_index, target_ts, target_ts, INT64_MAX, flags);
if (ret < 0)
// for compatibility reasons, seek to the best-fitting timestamp
ret = read_seek2(s, stream_index, INT64_MIN, target_ts, INT64_MAX, flags);
}
return ret;
}
#else
static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags){
MpegTSContext *ts = s->priv_data;
uint8_t buf[TS_PACKET_SIZE];
int64_t pos;
if(av_seek_frame_binary(s, stream_index, target_ts, flags) < 0)
return -1;
pos= avio_tell(s->pb);
for(;;) {
avio_seek(s->pb, pos, SEEK_SET);
if (avio_read(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
return -1;
// pid = AV_RB16(buf + 1) & 0x1fff;
if(buf[1] & 0x40) break;
pos += ts->raw_packet_size;
}
avio_seek(s->pb, pos, SEEK_SET);
return 0;
}
#endif
/**************************************************************/
/* parsing functions - called from other demuxers such as RTP */
MpegTSContext *ff_mpegts_parse_open(AVFormatContext *s)
{
MpegTSContext *ts;
ts = av_mallocz(sizeof(MpegTSContext));
if (!ts)
return NULL;
/* no stream case, currently used by RTP */
ts->raw_packet_size = TS_PACKET_SIZE;
ts->stream = s;
ts->auto_guess = 1;
return ts;
}
/* return the consumed length if a packet was output, or -1 if no
packet is output */
int ff_mpegts_parse_packet(MpegTSContext *ts, AVPacket *pkt,
const uint8_t *buf, int len)
{
int len1;
len1 = len;
ts->pkt = pkt;
ts->stop_parse = 0;
for(;;) {
if (ts->stop_parse>0)
break;
if (len < TS_PACKET_SIZE)
return -1;
if (buf[0] != 0x47) {
buf++;
len--;
} else {
handle_packet(ts, buf);
buf += TS_PACKET_SIZE;
len -= TS_PACKET_SIZE;
}
}
return len1 - len;
}
void ff_mpegts_parse_close(MpegTSContext *ts)
{
int i;
for(i=0;i<NB_PID_MAX;i++)
av_free(ts->pids[i]);
av_free(ts);
}
AVInputFormat ff_mpegts_demuxer = {
"mpegts",
NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
sizeof(MpegTSContext),
mpegts_probe,
mpegts_read_header,
mpegts_read_packet,
mpegts_read_close,
read_seek,
mpegts_get_pcr,
.flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
#ifdef USE_SYNCPOINT_SEARCH
.read_seek2 = read_seek2,
#endif
};
AVInputFormat ff_mpegtsraw_demuxer = {
"mpegtsraw",
NULL_IF_CONFIG_SMALL("MPEG-2 raw transport stream format"),
sizeof(MpegTSContext),
NULL,
mpegts_read_header,
mpegts_raw_read_packet,
mpegts_read_close,
read_seek,
mpegts_get_pcr,
.flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
#ifdef USE_SYNCPOINT_SEARCH
.read_seek2 = read_seek2,
#endif
.priv_class = &mpegtsraw_class,
};
Reference in New Issue View Git Blame Copy Permalink