/*

  * MPEG2 transport stream (aka DVB) muxer

  * Copyright (c) 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

  */

 #include "libavutil/bswap.h"

 #include "libavutil/crc.h"

 #include "libavutil/dict.h"

 #include "libavutil/mathematics.h"

 #include "libavutil/opt.h"

 #include "libavutil/avassert.h"

 #include "libavcodec/mpegvideo.h"

 #include "avformat.h"

 #include "internal.h"

 #include "mpegts.h"
 

 #define PCR_TIME_BASE 27000000
 

 /* write DVB SI sections */
 
 /*********************************************/
 /* mpegts section writer */
 
 typedef struct MpegTSSection {
     int pid;
     int cc;
     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
     void *opaque;
 } MpegTSSection;
 

 typedef struct MpegTSService {
     MpegTSSection pmt; /* MPEG2 pmt table context */
     int sid;           /* service ID */
     char *name;
     char *provider_name;
     int pcr_pid;
     int pcr_packet_count;

     int pcr_packet_period;

 } MpegTSService;
 
 typedef struct MpegTSWrite {

     const AVClass *av_class;

     MpegTSSection pat; /* MPEG2 pat table */
     MpegTSSection sdt; /* MPEG2 sdt table context */
     MpegTSService **services;
     int sdt_packet_count;

     int sdt_packet_period;

     int pat_packet_count;

     int pat_packet_period;

     int nb_services;
     int onid;
     int tsid;

     int64_t first_pcr;

     int mux_rate; ///< set to 1 when VBR

     int pes_payload_size;

 
     int transport_stream_id;
     int original_network_id;
     int service_id;
 
     int pmt_start_pid;
     int start_pid;

     int m2ts_mode;

     int reemit_pat_pmt; // backward compatibility
 
 #define MPEGTS_FLAG_REEMIT_PAT_PMT  0x01
 #define MPEGTS_FLAG_AAC_LATM        0x02
     int flags;

     int copyts;

 } MpegTSWrite;
 

 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
 #define DEFAULT_PES_HEADER_FREQ 16
 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
 

 static const AVOption options[] = {
     { "mpegts_transport_stream_id", "Set transport_stream_id field.",

       offsetof(MpegTSWrite, transport_stream_id), AV_OPT_TYPE_INT, {.i64 = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_original_network_id", "Set original_network_id field.",

       offsetof(MpegTSWrite, original_network_id), AV_OPT_TYPE_INT, {.i64 = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_service_id", "Set service_id field.",

       offsetof(MpegTSWrite, service_id), AV_OPT_TYPE_INT, {.i64 = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_pmt_start_pid", "Set the first pid of the PMT.",

       offsetof(MpegTSWrite, pmt_start_pid), AV_OPT_TYPE_INT, {.i64 = 0x1000 }, 0x0010, 0x1f00, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_start_pid", "Set the first pid.",

       offsetof(MpegTSWrite, start_pid), AV_OPT_TYPE_INT, {.i64 = 0x0100 }, 0x0100, 0x0f00, AV_OPT_FLAG_ENCODING_PARAM},

     {"mpegts_m2ts_mode", "Enable m2ts mode.",

         offsetof(MpegTSWrite, m2ts_mode), AV_OPT_TYPE_INT, {.i64 = -1 },

         -1,1, AV_OPT_FLAG_ENCODING_PARAM},

     { "muxrate", NULL, offsetof(MpegTSWrite, mux_rate), AV_OPT_TYPE_INT, {.i64 = 1}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},

     { "pes_payload_size", "Minimum PES packet payload in bytes",

       offsetof(MpegTSWrite, pes_payload_size), AV_OPT_TYPE_INT, {.i64 = DEFAULT_PES_PAYLOAD_SIZE}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_flags", "MPEG-TS muxing flags", offsetof(MpegTSWrite, flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, INT_MAX,

       AV_OPT_FLAG_ENCODING_PARAM, "mpegts_flags" },
     { "resend_headers", "Reemit PAT/PMT before writing the next packet",

       0, AV_OPT_TYPE_CONST, {.i64 = MPEGTS_FLAG_REEMIT_PAT_PMT}, 0, INT_MAX,

       AV_OPT_FLAG_ENCODING_PARAM, "mpegts_flags"},
     { "latm", "Use LATM packetization for AAC",

       0, AV_OPT_TYPE_CONST, {.i64 = MPEGTS_FLAG_AAC_LATM}, 0, INT_MAX,

       AV_OPT_FLAG_ENCODING_PARAM, "mpegts_flags"},
     // backward compatibility

     { "resend_headers", "Reemit PAT/PMT before writing the next packet",

       offsetof(MpegTSWrite, reemit_pat_pmt), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},

     { "mpegts_copyts", "dont offset dts/pts",

       offsetof(MpegTSWrite, copyts), AV_OPT_TYPE_INT, {.i64=-1}, -1, 1, AV_OPT_FLAG_ENCODING_PARAM},

     { NULL },
 };
 
 static const AVClass mpegts_muxer_class = {

     .class_name     = "MPEGTS muxer",
     .item_name      = av_default_item_name,
     .option         = options,
     .version        = LIBAVUTIL_VERSION_INT,

 };
 

 /* NOTE: 4 bytes must be left at the end for the crc32 */

 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)

 {
     unsigned int crc;
     unsigned char packet[TS_PACKET_SIZE];
     const unsigned char *buf_ptr;
     unsigned char *q;
     int first, b, len1, left;
 

     crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));

     buf[len - 4] = (crc >> 24) & 0xff;
     buf[len - 3] = (crc >> 16) & 0xff;
     buf[len - 2] = (crc >> 8) & 0xff;
     buf[len - 1] = (crc) & 0xff;

     /* send each packet */
     buf_ptr = buf;
     while (len > 0) {
         first = (buf == buf_ptr);
         q = packet;
         *q++ = 0x47;
         b = (s->pid >> 8);
         if (first)
             b |= 0x40;
         *q++ = b;
         *q++ = s->pid;

         s->cc = (s->cc + 1) & 0xf;

         *q++ = 0x10 | s->cc;

         if (first)
             *q++ = 0; /* 0 offset */
         len1 = TS_PACKET_SIZE - (q - packet);

         if (len1 > len)

             len1 = len;
         memcpy(q, buf_ptr, len1);
         q += len1;
         /* add known padding data */
         left = TS_PACKET_SIZE - (q - packet);
         if (left > 0)
             memset(q, 0xff, left);
 
         s->write_packet(s, packet);
 
         buf_ptr += len1;
         len -= len1;
     }
 }
 
 static inline void put16(uint8_t **q_ptr, int val)
 {
     uint8_t *q;
     q = *q_ptr;
     *q++ = val >> 8;
     *q++ = val;
     *q_ptr = q;
 }
 

 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,

                           int version, int sec_num, int last_sec_num,
                           uint8_t *buf, int len)
 {
     uint8_t section[1024], *q;
     unsigned int tot_len;

     /* reserved_future_use field must be set to 1 for SDT */
     unsigned int flags = tid == SDT_TID ? 0xf000 : 0xb000;

     tot_len = 3 + 5 + len + 4;
     /* check if not too big */
     if (tot_len > 1024)

         return AVERROR_INVALIDDATA;

 
     q = section;
     *q++ = tid;

     put16(&q, flags | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */

     put16(&q, id);
     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
     *q++ = sec_num;
     *q++ = last_sec_num;
     memcpy(q, buf, len);

     mpegts_write_section(s, section, tot_len);
     return 0;
 }
 
 /*********************************************/
 /* mpegts writer */
 

 #define DEFAULT_PROVIDER_NAME   "FFmpeg"

 #define DEFAULT_SERVICE_NAME    "Service01"
 
 /* we retransmit the SI info at this rate */
 #define SDT_RETRANS_TIME 500
 #define PAT_RETRANS_TIME 100

 #define PCR_RETRANS_TIME 20

 
 typedef struct MpegTSWriteStream {

     struct MpegTSService *service;

     int pid; /* stream associated pid */
     int cc;

     int payload_size;

     int first_pts_check; ///< first pts check needed

     int prev_payload_key;

     int64_t payload_pts;

     int64_t payload_dts;

     int payload_flags;

     uint8_t *payload;

     AVFormatContext *amux;

 } MpegTSWriteStream;
 
 static void mpegts_write_pat(AVFormatContext *s)
 {
     MpegTSWrite *ts = s->priv_data;
     MpegTSService *service;
     uint8_t data[1012], *q;
     int i;

     q = data;
     for(i = 0; i < ts->nb_services; i++) {
         service = ts->services[i];
         put16(&q, service->sid);
         put16(&q, 0xe000 | service->pmt.pid);
     }
     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
                           data, q - data);
 }
 

 static int mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)

 {

     MpegTSWrite *ts = s->priv_data;

     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
     int val, stream_type, i;
 
     q = data;
     put16(&q, 0xe000 | service->pcr_pid);
 
     program_info_length_ptr = q;
     q += 2; /* patched after */
 
     /* put program info here */
 
     val = 0xf000 | (q - program_info_length_ptr - 2);
     program_info_length_ptr[0] = val >> 8;
     program_info_length_ptr[1] = val;

     for(i = 0; i < s->nb_streams; i++) {
         AVStream *st = s->streams[i];
         MpegTSWriteStream *ts_st = st->priv_data;

         AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,0);

         switch(st->codec->codec_id) {

         case AV_CODEC_ID_MPEG1VIDEO:
         case AV_CODEC_ID_MPEG2VIDEO:

             stream_type = STREAM_TYPE_VIDEO_MPEG2;

             break;

         case AV_CODEC_ID_MPEG4:

             stream_type = STREAM_TYPE_VIDEO_MPEG4;
             break;

         case AV_CODEC_ID_H264:

             stream_type = STREAM_TYPE_VIDEO_H264;
             break;

         case AV_CODEC_ID_DIRAC:

             stream_type = STREAM_TYPE_VIDEO_DIRAC;
             break;

         case AV_CODEC_ID_MP2:
         case AV_CODEC_ID_MP3:

             stream_type = STREAM_TYPE_AUDIO_MPEG1;

             break;

         case AV_CODEC_ID_AAC:

             stream_type = (ts->flags & MPEGTS_FLAG_AAC_LATM) ? STREAM_TYPE_AUDIO_AAC_LATM : STREAM_TYPE_AUDIO_AAC;

             break;

         case AV_CODEC_ID_AAC_LATM:

             stream_type = STREAM_TYPE_AUDIO_AAC_LATM;
             break;

         case AV_CODEC_ID_AC3:

             stream_type = STREAM_TYPE_AUDIO_AC3;

             break;

         default:
             stream_type = STREAM_TYPE_PRIVATE_DATA;
             break;
         }

 
         if (q - data > sizeof(data) - 32)
             return AVERROR(EINVAL);
 

         *q++ = stream_type;
         put16(&q, 0xe000 | ts_st->pid);
         desc_length_ptr = q;
         q += 2; /* patched after */
 
         /* write optional descriptors here */

         switch(st->codec->codec_type) {

         case AVMEDIA_TYPE_AUDIO:

             if(st->codec->codec_id==AV_CODEC_ID_EAC3){

                 *q++=0x7a; // EAC3 descriptor see A038 DVB SI
                 *q++=1; // 1 byte, all flags sets to 0
                 *q++=0; // omit all fields...
             }

             if(st->codec->codec_id==AV_CODEC_ID_S302M){

                 *q++ = 0x05; /* MPEG-2 registration descriptor*/
                 *q++ = 4;
                 *q++ = 'B';
                 *q++ = 'S';
                 *q++ = 'S';
                 *q++ = 'D';
             }

             if (lang) {
                 char *p;
                 char *next = lang->value;
                 uint8_t *len_ptr;
 

                 *q++ = 0x0a; /* ISO 639 language descriptor */

                 len_ptr = q++;
                 *len_ptr = 0;
 

                 for (p = lang->value; next && *len_ptr < 255 / 4 * 4 && q - data < sizeof(data) - 4; p = next + 1) {

                     next = strchr(p, ',');
                     if (strlen(p) != 3 && (!next || next != p + 3))
                         continue; /* not a 3-letter code */
 
                     *q++ = *p++;
                     *q++ = *p++;
                     *q++ = *p++;
 

                 if (st->disposition & AV_DISPOSITION_CLEAN_EFFECTS)
                     *q++ = 0x01;
                 else if (st->disposition & AV_DISPOSITION_HEARING_IMPAIRED)
                     *q++ = 0x02;
                 else if (st->disposition & AV_DISPOSITION_VISUAL_IMPAIRED)
                     *q++ = 0x03;
                 else

                     *q++ = 0; /* undefined type */

 
                     *len_ptr += 4;
                 }
 
                 if (*len_ptr == 0)
                     q -= 2; /* no language codes were written */

             }
             break;

         case AVMEDIA_TYPE_SUBTITLE:

             {
                 const char *language;

                 language = lang && strlen(lang->value)==3 ? lang->value : "eng";

                 *q++ = 0x59;
                 *q++ = 8;
                 *q++ = language[0];
                 *q++ = language[1];
                 *q++ = language[2];
                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */

                 if(st->codec->extradata_size == 4) {
                     memcpy(q, st->codec->extradata, 4);
                     q += 4;
                 } else {

                     put16(&q, 1); /* page id */
                     put16(&q, 1); /* ancillary page id */

                 }

             }
             break;

         case AVMEDIA_TYPE_VIDEO:

             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
                 *q++ = 4;
                 *q++ = 'd';
                 *q++ = 'r';
                 *q++ = 'a';
                 *q++ = 'c';
             }
             break;

         }

 
         val = 0xf000 | (q - desc_length_ptr - 2);
         desc_length_ptr[0] = val >> 8;
         desc_length_ptr[1] = val;
     }
     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
                           data, q - data);

     return 0;

 }

 
 /* NOTE: str == NULL is accepted for an empty string */
 static void putstr8(uint8_t **q_ptr, const char *str)
 {
     uint8_t *q;
     int len;
 
     q = *q_ptr;
     if (!str)
         len = 0;
     else
         len = strlen(str);
     *q++ = len;
     memcpy(q, str, len);
     q += len;
     *q_ptr = q;
 }
 
 static void mpegts_write_sdt(AVFormatContext *s)
 {
     MpegTSWrite *ts = s->priv_data;
     MpegTSService *service;
     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
     int i, running_status, free_ca_mode, val;

     q = data;
     put16(&q, ts->onid);
     *q++ = 0xff;
     for(i = 0; i < ts->nb_services; i++) {
         service = ts->services[i];
         put16(&q, service->sid);
         *q++ = 0xfc | 0x00; /* currently no EIT info */
         desc_list_len_ptr = q;
         q += 2;
         running_status = 4; /* running */
         free_ca_mode = 0;
 
         /* write only one descriptor for the service name and provider */
         *q++ = 0x48;
         desc_len_ptr = q;
         q++;
         *q++ = 0x01; /* digital television service */
         putstr8(&q, service->provider_name);
         putstr8(&q, service->name);
         desc_len_ptr[0] = q - desc_len_ptr - 1;
 
         /* fill descriptor length */

         val = (running_status << 13) | (free_ca_mode << 12) |

             (q - desc_list_len_ptr - 2);
         desc_list_len_ptr[0] = val >> 8;
         desc_list_len_ptr[1] = val;
     }
     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
                           data, q - data);
 }
 

 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
                                          int sid,
                                          const char *provider_name,

                                          const char *name)
 {
     MpegTSService *service;
 
     service = av_mallocz(sizeof(MpegTSService));
     if (!service)
         return NULL;

     service->pmt.pid = ts->pmt_start_pid + ts->nb_services;

     service->sid = sid;
     service->provider_name = av_strdup(provider_name);
     service->name = av_strdup(name);
     service->pcr_pid = 0x1fff;
     dynarray_add(&ts->services, &ts->nb_services, service);
     return service;
 }
 

 static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
 {
     return av_rescale(avio_tell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +
            ts->first_pcr;
 }
 
 static void mpegts_prefix_m2ts_header(AVFormatContext *s)
 {
     MpegTSWrite *ts = s->priv_data;
     if (ts->m2ts_mode) {
         int64_t pcr = get_pcr(s->priv_data, s->pb);
         uint32_t tp_extra_header = pcr % 0x3fffffff;
         tp_extra_header = AV_RB32(&tp_extra_header);
         avio_write(s->pb, (unsigned char *) &tp_extra_header,
                 sizeof(tp_extra_header));
     }
 }
 

 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
 {
     AVFormatContext *ctx = s->opaque;

     mpegts_prefix_m2ts_header(ctx);

     avio_write(ctx->pb, packet, TS_PACKET_SIZE);

 }
 
 static int mpegts_write_header(AVFormatContext *s)
 {
     MpegTSWrite *ts = s->priv_data;
     MpegTSWriteStream *ts_st;
     MpegTSService *service;

     AVStream *st, *pcr_st = NULL;

     AVDictionaryEntry *title, *provider;

     int i, j;

     const char *service_name;

     const char *provider_name;

     int *pids;

     int ret;

     if (s->max_delay < 0) /* Not set by the caller */
         s->max_delay = 0;
 

     // round up to a whole number of TS packets
     ts->pes_payload_size = (ts->pes_payload_size + 14 + 183) / 184 * 184 - 14;
 

     ts->tsid = ts->transport_stream_id;
     ts->onid = ts->original_network_id;

     /* allocate a single DVB service */

     title = av_dict_get(s->metadata, "service_name", NULL, 0);

     if (!title)

         title = av_dict_get(s->metadata, "title", NULL, 0);

     service_name = title ? title->value : DEFAULT_SERVICE_NAME;

     provider = av_dict_get(s->metadata, "service_provider", NULL, 0);

     provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;

     service = mpegts_add_service(ts, ts->service_id, provider_name, service_name);

     service->pmt.write_packet = section_write_packet;
     service->pmt.opaque = s;

     service->pmt.cc = 15;

 
     ts->pat.pid = PAT_PID;

     ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write

     ts->pat.write_packet = section_write_packet;
     ts->pat.opaque = s;
 
     ts->sdt.pid = SDT_PID;

     ts->sdt.cc = 15;

     ts->sdt.write_packet = section_write_packet;
     ts->sdt.opaque = s;
 

     pids = av_malloc(s->nb_streams * sizeof(*pids));

     if (!pids)
         return AVERROR(ENOMEM);
 

     /* assign pids to each stream */
     for(i = 0;i < s->nb_streams; i++) {
         st = s->streams[i];

         avpriv_set_pts_info(st, 33, 1, 90000);

         ts_st = av_mallocz(sizeof(MpegTSWriteStream));

         if (!ts_st) {
             ret = AVERROR(ENOMEM);

             goto fail;

         }

         st->priv_data = ts_st;

         ts_st->payload = av_mallocz(ts->pes_payload_size);

         if (!ts_st->payload) {
             ret = AVERROR(ENOMEM);

             goto fail;

         }

         ts_st->service = service;

         /* MPEG pid values < 16 are reserved. Applications which set st->id in
          * this range are assigned a calculated pid. */
         if (st->id < 16) {

             ts_st->pid = ts->start_pid + i;

         } else if (st->id < 0x1FFF) {
             ts_st->pid = st->id;
         } else {
             av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);

             ret = AVERROR(EINVAL);

             goto fail;
         }
         if (ts_st->pid == service->pmt.pid) {
             av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);

             ret = AVERROR(EINVAL);

             goto fail;
         }
         for (j = 0; j < i; j++)
             if (pids[j] == ts_st->pid) {
                 av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);

                 ret = AVERROR(EINVAL);

                 goto fail;
             }
         pids[i] = ts_st->pid;

         ts_st->payload_pts = AV_NOPTS_VALUE;

         ts_st->payload_dts = AV_NOPTS_VALUE;

         ts_st->first_pts_check = 1;

         ts_st->cc = 15;

         /* update PCR pid by using the first video stream */

         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&

             service->pcr_pid == 0x1fff) {

             service->pcr_pid = ts_st->pid;

             pcr_st = st;

         }

         if (st->codec->codec_id == AV_CODEC_ID_AAC &&

             st->codec->extradata_size > 0)
         {
             AVStream *ast;
             ts_st->amux = avformat_alloc_context();
             if (!ts_st->amux) {
                 ret = AVERROR(ENOMEM);

                 goto fail;

             }

             ts_st->amux->oformat = av_guess_format((ts->flags & MPEGTS_FLAG_AAC_LATM) ? "latm" : "adts", NULL, NULL);
             if (!ts_st->amux->oformat) {
                 ret = AVERROR(EINVAL);
                 goto fail;
             }

             ast = avformat_new_stream(ts_st->amux, NULL);
             ret = avcodec_copy_context(ast->codec, st->codec);
             if (ret != 0)
                 goto fail;
             ret = avformat_write_header(ts_st->amux, NULL);
             if (ret < 0)

                 goto fail;

         }

     }

     av_free(pids);
 

     /* if no video stream, use the first stream as PCR */
     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {

         pcr_st = s->streams[0];
         ts_st = pcr_st->priv_data;

         service->pcr_pid = ts_st->pid;
     }
 

     if (ts->mux_rate > 1) {

         service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
             (TS_PACKET_SIZE * 8 * 1000);
         ts->sdt_packet_period      = (ts->mux_rate * SDT_RETRANS_TIME) /
             (TS_PACKET_SIZE * 8 * 1000);
         ts->pat_packet_period      = (ts->mux_rate * PAT_RETRANS_TIME) /
             (TS_PACKET_SIZE * 8 * 1000);
 

         if(ts->copyts < 1)
             ts->first_pcr = av_rescale(s->max_delay, PCR_TIME_BASE, AV_TIME_BASE);

     } else {

         /* Arbitrary values, PAT/PMT will also be written on video key frames */

         ts->sdt_packet_period = 200;
         ts->pat_packet_period = 40;

         if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {

             if (!pcr_st->codec->frame_size) {
                 av_log(s, AV_LOG_WARNING, "frame size not set\n");
                 service->pcr_packet_period =
                     pcr_st->codec->sample_rate/(10*512);
             } else {
                 service->pcr_packet_period =
                     pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
             }
         } else {
             // max delta PCR 0.1s
             service->pcr_packet_period =
                 pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
         }

         if(!service->pcr_packet_period)
             service->pcr_packet_period = 1;

     }
 

     // output a PCR as soon as possible
     service->pcr_packet_count = service->pcr_packet_period;

     ts->pat_packet_count = ts->pat_packet_period-1;
     ts->sdt_packet_count = ts->sdt_packet_period-1;

     if (ts->mux_rate == 1)

         av_log(s, AV_LOG_VERBOSE, "muxrate VBR, ");

     else

         av_log(s, AV_LOG_VERBOSE, "muxrate %d, ", ts->mux_rate);
     av_log(s, AV_LOG_VERBOSE, "pcr every %d pkts, "

            "sdt every %d, pat/pmt every %d pkts\n",

            service->pcr_packet_period,

            ts->sdt_packet_period, ts->pat_packet_period);

     if (ts->m2ts_mode == -1) {
         if (av_match_ext(s->filename, "m2ts")) {
             ts->m2ts_mode = 1;
         } else {
             ts->m2ts_mode = 0;
         }
     }
 

     avio_flush(s->pb);

 
     return 0;
 
  fail:

     av_free(pids);

     for(i = 0;i < s->nb_streams; i++) {

         MpegTSWriteStream *ts_st;

         st = s->streams[i];

         ts_st = st->priv_data;
         if (ts_st) {
             av_freep(&ts_st->payload);

             if (ts_st->amux) {
                 avformat_free_context(ts_st->amux);

                 ts_st->amux = NULL;

             }

         }

         av_freep(&st->priv_data);

     }

     return ret;

 }
 
 /* send SDT, PAT and PMT tables regulary */

 static void retransmit_si_info(AVFormatContext *s, int force_pat)

 {
     MpegTSWrite *ts = s->priv_data;
     int i;
 

     if (++ts->sdt_packet_count == ts->sdt_packet_period) {

         ts->sdt_packet_count = 0;
         mpegts_write_sdt(s);
     }

     if (++ts->pat_packet_count == ts->pat_packet_period || force_pat) {

         ts->pat_packet_count = 0;
         mpegts_write_pat(s);
         for(i = 0; i < ts->nb_services; i++) {
             mpegts_write_pmt(s, ts->services[i]);
         }
     }
 }
 

 static int write_pcr_bits(uint8_t *buf, int64_t pcr)

 {
     int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;
 
     *buf++ = pcr_high >> 25;
     *buf++ = pcr_high >> 17;
     *buf++ = pcr_high >> 9;
     *buf++ = pcr_high >> 1;

     *buf++ = pcr_high << 7 | pcr_low >> 8 | 0x7e;

     *buf++ = pcr_low;
 

     return 6;

 }
 

 /* Write a single null transport stream packet */
 static void mpegts_insert_null_packet(AVFormatContext *s)
 {
     uint8_t *q;
     uint8_t buf[TS_PACKET_SIZE];
 
     q = buf;
     *q++ = 0x47;
     *q++ = 0x00 | 0x1f;
     *q++ = 0xff;
     *q++ = 0x10;
     memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));

     mpegts_prefix_m2ts_header(s);

     avio_write(s->pb, buf, TS_PACKET_SIZE);

 }
 
 /* Write a single transport stream packet with a PCR and no payload */
 static void mpegts_insert_pcr_only(AVFormatContext *s, AVStream *st)
 {
     MpegTSWrite *ts = s->priv_data;
     MpegTSWriteStream *ts_st = st->priv_data;
     uint8_t *q;
     uint8_t buf[TS_PACKET_SIZE];
 
     q = buf;
     *q++ = 0x47;
     *q++ = ts_st->pid >> 8;
     *q++ = ts_st->pid;
     *q++ = 0x20 | ts_st->cc;   /* Adaptation only */
     /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
     *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
     *q++ = 0x10;               /* Adaptation flags: PCR present */
 
     /* PCR coded into 6 bytes */

     q += write_pcr_bits(q, get_pcr(ts, s->pb));

 
     /* stuffing bytes */
     memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));

     mpegts_prefix_m2ts_header(s);

     avio_write(s->pb, buf, TS_PACKET_SIZE);

 }
 

 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
 {
     int val;
 
     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
     *q++ = val;
     val = (((pts >> 15) & 0x7fff) << 1) | 1;
     *q++ = val >> 8;
     *q++ = val;
     val = (((pts) & 0x7fff) << 1) | 1;
     *q++ = val >> 8;
     *q++ = val;
 }
 

 /* Set an adaptation field flag in an MPEG-TS packet*/
 static void set_af_flag(uint8_t *pkt, int flag)
 {
     // expect at least one flag to set

     av_assert0(flag);

 
     if ((pkt[3] & 0x20) == 0) {
         // no AF yet, set adaptation field flag
         pkt[3] |= 0x20;
         // 1 byte length, no flags
         pkt[4] = 1;
         pkt[5] = 0;
     }
     pkt[5] |= flag;
 }
 
 /* Extend the adaptation field by size bytes */
 static void extend_af(uint8_t *pkt, int size)
 {
     // expect already existing adaptation field

     av_assert0(pkt[3] & 0x20);

     pkt[4] += size;
 }
 
 /* Get a pointer to MPEG-TS payload (right after TS packet header) */
 static uint8_t *get_ts_payload_start(uint8_t *pkt)
 {
     if (pkt[3] & 0x20)
         return pkt + 5 + pkt[4];
     else
         return pkt + 4;
 }
 

 /* Add a pes header to the front of payload, and segment into an integer number of
  * ts packets. The final ts packet is padded using an over-sized adaptation header
  * to exactly fill the last ts packet.
  * NOTE: 'payload' contains a complete PES payload.
  */

 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
                              const uint8_t *payload, int payload_size,

                              int64_t pts, int64_t dts, int key)

 {
     MpegTSWriteStream *ts_st = st->priv_data;

     MpegTSWrite *ts = s->priv_data;

     uint8_t buf[TS_PACKET_SIZE];

     uint8_t *q;

     int val, is_start, len, header_len, write_pcr, private_code, flags;

     int afc_len, stuffing_len;
     int64_t pcr = -1; /* avoid warning */

     int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);

     int force_pat = st->codec->codec_type == AVMEDIA_TYPE_VIDEO && key && !ts_st->prev_payload_key;

     is_start = 1;
     while (payload_size > 0) {

         retransmit_si_info(s, force_pat);
         force_pat = 0;

         write_pcr = 0;
         if (ts_st->pid == ts_st->service->pcr_pid) {

             if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
                 ts_st->service->pcr_packet_count++;

             if (ts_st->service->pcr_packet_count >=

                 ts_st->service->pcr_packet_period) {

                 ts_st->service->pcr_packet_count = 0;
                 write_pcr = 1;
             }
         }
 

         if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&

             (dts - get_pcr(ts, s->pb)/300) > delay) {

             /* pcr insert gets priority over null packet insert */
             if (write_pcr)
                 mpegts_insert_pcr_only(s, st);
             else
                 mpegts_insert_null_packet(s);
             continue; /* recalculate write_pcr and possibly retransmit si_info */
         }
 

         /* prepare packet header */
         q = buf;
         *q++ = 0x47;
         val = (ts_st->pid >> 8);
         if (is_start)
             val |= 0x40;
         *q++ = val;
         *q++ = ts_st->pid;
         ts_st->cc = (ts_st->cc + 1) & 0xf;

         *q++ = 0x10 | ts_st->cc; // payload indicator + CC
         if (key && is_start && pts != AV_NOPTS_VALUE) {
             // set Random Access for key frames
             if (ts_st->pid == ts_st->service->pcr_pid)
                 write_pcr = 1;
             set_af_flag(buf, 0x40);
             q = get_ts_payload_start(buf);
         }

         if (write_pcr) {

             set_af_flag(buf, 0x10);
             q = get_ts_payload_start(buf);

             // add 11, pcr references the last byte of program clock reference base

             if (ts->mux_rate > 1)

                 pcr = get_pcr(ts, s->pb);

             else

                 pcr = (dts - delay)*300;
             if (dts != AV_NOPTS_VALUE && dts < pcr / 300)

                 av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");

             extend_af(buf, write_pcr_bits(q, pcr));
             q = get_ts_payload_start(buf);

         }

         if (is_start) {

             int pes_extension = 0;

             /* write PES header */
             *q++ = 0x00;
             *q++ = 0x00;
             *q++ = 0x01;

             private_code = 0;

             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

                 if (st->codec->codec_id == AV_CODEC_ID_DIRAC) {

                     *q++ = 0xfd;
                 } else
                     *q++ = 0xe0;

             } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&

                        (st->codec->codec_id == AV_CODEC_ID_MP2 ||
                         st->codec->codec_id == AV_CODEC_ID_MP3 ||
                         st->codec->codec_id == AV_CODEC_ID_AAC)) {

                 *q++ = 0xc0;

             } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&

                         st->codec->codec_id == AV_CODEC_ID_AC3 &&

                         ts->m2ts_mode) {
                 *q++ = 0xfd;

             } else {
                 *q++ = 0xbd;

                 if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {

                     private_code = 0x20;
                 }
             }

             header_len = 0;
             flags = 0;
             if (pts != AV_NOPTS_VALUE) {
                 header_len += 5;
                 flags |= 0x80;
             }

             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {

                 header_len += 5;
                 flags |= 0x40;
             }

             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&

                 st->codec->codec_id == AV_CODEC_ID_DIRAC) {

                 /* set PES_extension_flag */
                 pes_extension = 1;
                 flags |= 0x01;
 
                 /*
                 * One byte for PES2 extension flag +
                 * one byte for extension length +
                 * one byte for extension id
                 */
                 header_len += 3;
             }

             /* for Blu-ray AC3 Audio the PES Extension flag should be as follow
              * otherwise it will not play sound on blu-ray
              */
             if (ts->m2ts_mode &&
                 st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&

                 st->codec->codec_id == AV_CODEC_ID_AC3) {

                         /* set PES_extension_flag */
                         pes_extension = 1;
                         flags |= 0x01;
                         header_len += 3;
             }

             len = payload_size + header_len + 3;

             if (private_code != 0)

                 len++;

             if (len > 0xffff)
                 len = 0;

             *q++ = len >> 8;
             *q++ = len;

             val = 0x80;
             /* data alignment indicator is required for subtitle data */

             if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE)

                 val |= 0x04;
             *q++ = val;

             *q++ = flags;
             *q++ = header_len;

             if (pts != AV_NOPTS_VALUE) {

                 write_pts(q, flags >> 6, pts);
                 q += 5;
             }

             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {

                 write_pts(q, 1, dts);
                 q += 5;

             }

             if (pes_extension && st->codec->codec_id == AV_CODEC_ID_DIRAC) {

                 flags = 0x01;  /* set PES_extension_flag_2 */
                 *q++ = flags;
                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
                 /*
                 * Set the stream id extension flag bit to 0 and
                 * write the extended stream id
                 */
                 *q++ = 0x00 | 0x60;
             }

             /* For Blu-ray AC3 Audio Setting extended flags */
           if (ts->m2ts_mode &&
               pes_extension &&

               st->codec->codec_id == AV_CODEC_ID_AC3) {

                       flags = 0x01; /* set PES_extension_flag_2 */
                       *q++ = flags;
                       *q++ = 0x80 | 0x01; /* marker bit + extension length */
                       *q++ = 0x00 | 0x71; /* for AC3 Audio (specifically on blue-rays) */
               }
 
 

             if (private_code != 0)
                 *q++ = private_code;

             is_start = 0;

         }

         /* header size */
         header_len = q - buf;
         /* data len */
         len = TS_PACKET_SIZE - header_len;

         if (len > payload_size)
             len = payload_size;

         stuffing_len = TS_PACKET_SIZE - header_len - len;
         if (stuffing_len > 0) {
             /* add stuffing with AFC */
             if (buf[3] & 0x20) {
                 /* stuffing already present: increase its size */
                 afc_len = buf[4] + 1;
                 memmove(buf + 4 + afc_len + stuffing_len,

                         buf + 4 + afc_len,

                         header_len - (4 + afc_len));
                 buf[4] += stuffing_len;
                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
             } else {
                 /* add stuffing */
                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
                 buf[3] |= 0x20;
                 buf[4] = stuffing_len - 1;
                 if (stuffing_len >= 2) {
                     buf[5] = 0x00;
                     memset(buf + 6, 0xff, stuffing_len - 2);
                 }
             }
         }
         memcpy(buf + TS_PACKET_SIZE - len, payload, len);

         payload += len;
         payload_size -= len;

         mpegts_prefix_m2ts_header(s);

         avio_write(s->pb, buf, TS_PACKET_SIZE);

     }

     avio_flush(s->pb);

     ts_st->prev_payload_key = key;

 }
 

 static int mpegts_write_packet_internal(AVFormatContext *s, AVPacket *pkt)

 {

     AVStream *st = s->streams[pkt->stream_index];

     int size = pkt->size;

     uint8_t *buf= pkt->data;

     uint8_t *data= NULL;

     MpegTSWrite *ts = s->priv_data;

     MpegTSWriteStream *ts_st = st->priv_data;

     const int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;

     int64_t dts = pkt->dts, pts = pkt->pts;

     if (ts->reemit_pat_pmt) {

         av_log(s, AV_LOG_WARNING, "resend_headers option is deprecated, use -mpegts_flags resend_headers\n");
         ts->reemit_pat_pmt = 0;
         ts->flags |= MPEGTS_FLAG_REEMIT_PAT_PMT;
     }
 
     if (ts->flags & MPEGTS_FLAG_REEMIT_PAT_PMT) {

         ts->pat_packet_count = ts->pat_packet_period - 1;
         ts->sdt_packet_count = ts->sdt_packet_period - 1;

         ts->flags &= ~MPEGTS_FLAG_REEMIT_PAT_PMT;

     }
 

     if(ts->copyts < 1){
         if (pts != AV_NOPTS_VALUE)
             pts += delay;
         if (dts != AV_NOPTS_VALUE)
             dts += delay;
     }

     if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {

         av_log(s, AV_LOG_ERROR, "first pts value must be set\n");

         return AVERROR_INVALIDDATA;

     }
     ts_st->first_pts_check = 0;
 

     if (st->codec->codec_id == AV_CODEC_ID_H264) {

         const uint8_t *p = buf, *buf_end = p+size;
         uint32_t state = -1;
 

         if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {

             av_log(s, AV_LOG_ERROR, "H.264 bitstream malformed, "

                    "no startcode found, use the h264_mp4toannexb bitstream filter (-bsf h264_mp4toannexb)\n");

             return AVERROR(EINVAL);

         }

 
         do {

             p = avpriv_mpv_find_start_code(p, buf_end, &state);

             av_dlog(s, "nal %d\n", state & 0x1f);

         } while (p < buf_end && (state & 0x1f) != 9 &&
                  (state & 0x1f) != 5 && (state & 0x1f) != 1);
 
         if ((state & 0x1f) != 9) { // AUD NAL

             data = av_malloc(pkt->size+6);
             if (!data)

                 return AVERROR(ENOMEM);

             memcpy(data+6, pkt->data, pkt->size);
             AV_WB32(data, 0x00000001);
             data[4] = 0x09;

             data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bit

             buf  = data;
             size = pkt->size+6;
         }

     } else if (st->codec->codec_id == AV_CODEC_ID_AAC) {

         if (pkt->size < 2) {
             av_log(s, AV_LOG_ERROR, "AAC packet too short\n");

             return AVERROR_INVALIDDATA;

         }

         if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {

             int ret;
             AVPacket pkt2;
 
             if (!ts_st->amux) {

                 av_log(s, AV_LOG_ERROR, "AAC bitstream not in ADTS format "

                        "and extradata missing\n");

                 return AVERROR_INVALIDDATA;

             }

 
             av_init_packet(&pkt2);
             pkt2.data = pkt->data;
             pkt2.size = pkt->size;

             ret = avio_open_dyn_buf(&ts_st->amux->pb);
             if (ret < 0)

                 return AVERROR(ENOMEM);

 
             ret = av_write_frame(ts_st->amux, &pkt2);
             if (ret < 0) {

                 avio_close_dyn_buf(ts_st->amux->pb, &data);
                 ts_st->amux->pb = NULL;

                 av_free(data);

                 return ret;

             }

             size = avio_close_dyn_buf(ts_st->amux->pb, &data);
             ts_st->amux->pb = NULL;
             buf = data;

         }

     }
 

     if (pkt->dts != AV_NOPTS_VALUE) {
         int i;
         for(i=0; i<s->nb_streams; i++){
             AVStream *st2 = s->streams[i];
             MpegTSWriteStream *ts_st2 = st2->priv_data;
             if(   ts_st2->payload_size

                && (ts_st2->payload_dts == AV_NOPTS_VALUE || dts - ts_st2->payload_dts > delay/2)){

                 mpegts_write_pes(s, st2, ts_st2->payload, ts_st2->payload_size,
                                 ts_st2->payload_pts, ts_st2->payload_dts,
                                 ts_st2->payload_flags & AV_PKT_FLAG_KEY);
                 ts_st2->payload_size = 0;

             }
         }
     }
 

     if (ts_st->payload_size && ts_st->payload_size + size > ts->pes_payload_size) {

         mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,

                          ts_st->payload_pts, ts_st->payload_dts,
                          ts_st->payload_flags & AV_PKT_FLAG_KEY);

         ts_st->payload_size = 0;

     }
 

     if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO || size > ts->pes_payload_size) {

         av_assert0(!ts_st->payload_size);

         // for video and subtitle, write a single pes packet
         mpegts_write_pes(s, st, buf, size, pts, dts, pkt->flags & AV_PKT_FLAG_KEY);
         av_free(data);
         return 0;
     }
 

     if (!ts_st->payload_size) {

         ts_st->payload_pts = pts;
         ts_st->payload_dts = dts;

         ts_st->payload_flags = pkt->flags;

     }

     memcpy(ts_st->payload + ts_st->payload_size, buf, size);
     ts_st->payload_size += size;

     av_free(data);
 

     return 0;
 }
 

 static void mpegts_write_flush(AVFormatContext *s)

 {
     int i;
 
     /* flush current packets */
     for(i = 0; i < s->nb_streams; i++) {

         AVStream *st = s->streams[i];
         MpegTSWriteStream *ts_st = st->priv_data;

         if (ts_st->payload_size > 0) {
             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,

                              ts_st->payload_pts, ts_st->payload_dts,
                              ts_st->payload_flags & AV_PKT_FLAG_KEY);

             ts_st->payload_size = 0;

         }

     }
     avio_flush(s->pb);
 }
 
 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     if (!pkt) {
         mpegts_write_flush(s);
         return 1;
     } else {
         return mpegts_write_packet_internal(s, pkt);
     }
 }
 
 static int mpegts_write_end(AVFormatContext *s)
 {
     MpegTSWrite *ts = s->priv_data;
     MpegTSService *service;
     int i;
 
     mpegts_write_flush(s);
 
     for(i = 0; i < s->nb_streams; i++) {
         AVStream *st = s->streams[i];
         MpegTSWriteStream *ts_st = st->priv_data;

         av_freep(&ts_st->payload);

         if (ts_st->amux) {
             avformat_free_context(ts_st->amux);

             ts_st->amux = NULL;

         }

     }

     for(i = 0; i < ts->nb_services; i++) {
         service = ts->services[i];
         av_freep(&service->provider_name);
         av_freep(&service->name);
         av_free(service);
     }
     av_free(ts->services);
 
     return 0;
 }
 

 AVOutputFormat ff_mpegts_muxer = {

     .name              = "mpegts",

     .long_name         = NULL_IF_CONFIG_SMALL("MPEG-TS (MPEG-2 Transport Stream)"),

     .mime_type         = "video/x-mpegts",

     .extensions        = "ts,m2t,m2ts,mts",

     .priv_data_size    = sizeof(MpegTSWrite),

     .audio_codec       = AV_CODEC_ID_MP2,
     .video_codec       = AV_CODEC_ID_MPEG2VIDEO,

     .write_header      = mpegts_write_header,
     .write_packet      = mpegts_write_packet,
     .write_trailer     = mpegts_write_end,

     .flags             = AVFMT_ALLOW_FLUSH,

     .priv_class        = &mpegts_muxer_class,

 };