/*

  * 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/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 = 2;

     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;

     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);

     expected_cc = (packet[3] & 0x10) ? (tss->last_cc + 1) & 0x0f : tss->last_cc;
     cc_ok = (tss->last_cc < 0) || (expected_cc == 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(;;) {

         packet_num++;

         if (nb_packets != 0 && packet_num >= nb_packets ||
             ts->stop_parse > 1) {
             ret = AVERROR(EAGAIN);
             break;
         }
         if (ts->stop_parse > 0)

             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;
     for(;;) {

         ts->stop_parse = 0;

         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;

             if (ts->stop_parse == 1)
                 break;

         }
     }
     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,

 };