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ffmpeg/libavformat/mpegts.c
Carl Eugen Hoyos c41bf905f4 Only autodetect loas in transport streams. 
The Makito encoder sets stream type 0x11 for AAC.
This patch should be reverted if it breaks decoding valid streams (and
the problem can't be fixed in the probe function).
2011-08-30 10:46:51 +02:00

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/*
* 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 USE_SYNCPOINT_SEARCH
#include "libavutil/crc.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/log.h"
#include "libavutil/dict.h"
#include "libavutil/mathematics.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 flags; /**< copied to the AVPacket flags */
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 },
/* Makito encoder sets stream type 0x11 for AAC,
* so auto-detect LOAS/LATM instead of hardcoding it. */
// { 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;
if(pes->total_size != MAX_PES_PAYLOAD &&
pes->pes_header_size + pes->data_index != pes->total_size + 6) {
av_log(pes->stream, AV_LOG_WARNING, "PES packet size mismatch\n");
pes->flags |= AV_PKT_FLAG_CORRUPT;
}
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;
pkt->flags = pes->flags;
/* reset pts values */
pes->pts = AV_NOPTS_VALUE;
pes->dts = AV_NOPTS_VALUE;
pes->buffer = NULL;
pes->data_index = 0;
pes->flags = 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) {
ff_mp4_parse_es_descr(&pb, es_id);
av_dlog(s, "ES_ID %#x\n", *es_id);
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, expected_cc, cc_ok, afc, is_start, is_discontinuity,
has_adaptation, has_payload;
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;
afc = (packet[3] >> 4) & 3;
if (afc == 0) /* reserved value */
return 0;
has_adaptation = afc & 2;
has_payload = afc & 1;
is_discontinuity = has_adaptation
&& packet[4] != 0 /* with length > 0 */
&& (packet[5] & 0x80); /* and discontinuity indicated */
/* continuity check (currently not used) */
cc = (packet[3] & 0xf);
expected_cc = has_payload ? (tss->last_cc + 1) & 0x0f : tss->last_cc;
cc_ok = pid == 0x1FFF // null packet PID
|| is_discontinuity
|| tss->last_cc < 0
|| expected_cc == cc;
tss->last_cc = cc;
if (!cc_ok) {
av_log(ts->stream, AV_LOG_WARNING, "Continuity Check Failed\n");
if(tss->type == MPEGTS_PES) {
PESContext *pc = tss->u.pes_filter.opaque;
pc->flags |= AV_PKT_FLAG_CORRUPT;
}
}
if (!has_payload)
return 0;
p = packet + 4;
if (has_adaptation) {
/* 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 = 0;
if (avio_tell(s->pb) != ts->last_pos) {
int i;
// av_dlog("Skipping after seek\n");
/* 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);
ts->pids[i]->last_cc = -1;
pes->data_index = 0;
pes->state = MPEGTS_SKIP; /* skip until pes header */
}
}
}
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)
break;
ret = handle_packet(ts, packet);
if (ret != 0)
break;
}
ts->last_pos = avio_tell(s->pb);
return ret;
}
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;
/* 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 (pb->seekable && 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;
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;
}
}
}
}
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 = {
.name = "mpegts",
.long_name = NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
.priv_data_size = sizeof(MpegTSContext),
.read_probe = mpegts_probe,
.read_header = mpegts_read_header,
.read_packet = mpegts_read_packet,
.read_close = mpegts_read_close,
.read_seek = read_seek,
.read_timestamp = mpegts_get_pcr,
.flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
#ifdef USE_SYNCPOINT_SEARCH
.read_seek2 = read_seek2,
#endif
};
AVInputFormat ff_mpegtsraw_demuxer = {
.name = "mpegtsraw",
.long_name = NULL_IF_CONFIG_SMALL("MPEG-2 raw transport stream format"),
.priv_data_size = sizeof(MpegTSContext),
.read_header = mpegts_read_header,
.read_packet = mpegts_raw_read_packet,
.read_close = mpegts_read_close,
.read_seek = read_seek,
.read_timestamp = mpegts_get_pcr,
.flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
#ifdef USE_SYNCPOINT_SEARCH
.read_seek2 = read_seek2,
#endif
.priv_class = &mpegtsraw_class,
};
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