libavformat/mpegtsenc.c
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00001 /*
00002  * MPEG2 transport stream (aka DVB) muxer
00003  * Copyright (c) 2003 Fabrice Bellard
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/bswap.h"
00023 #include "libavutil/crc.h"
00024 #include "libavutil/dict.h"
00025 #include "libavutil/mathematics.h"
00026 #include "libavutil/opt.h"
00027 #include "libavcodec/mpegvideo.h"
00028 #include "avformat.h"
00029 #include "internal.h"
00030 #include "mpegts.h"
00031 #include "adts.h"
00032 
00033 #define PCR_TIME_BASE 27000000
00034 
00035 /* write DVB SI sections */
00036 
00037 /*********************************************/
00038 /* mpegts section writer */
00039 
00040 typedef struct MpegTSSection {
00041     int pid;
00042     int cc;
00043     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
00044     void *opaque;
00045 } MpegTSSection;
00046 
00047 typedef struct MpegTSService {
00048     MpegTSSection pmt; /* MPEG2 pmt table context */
00049     int sid;           /* service ID */
00050     char *name;
00051     char *provider_name;
00052     int pcr_pid;
00053     int pcr_packet_count;
00054     int pcr_packet_period;
00055 } MpegTSService;
00056 
00057 typedef struct MpegTSWrite {
00058     const AVClass *av_class;
00059     MpegTSSection pat; /* MPEG2 pat table */
00060     MpegTSSection sdt; /* MPEG2 sdt table context */
00061     MpegTSService **services;
00062     int sdt_packet_count;
00063     int sdt_packet_period;
00064     int pat_packet_count;
00065     int pat_packet_period;
00066     int nb_services;
00067     int onid;
00068     int tsid;
00069     int64_t first_pcr;
00070     int mux_rate; 
00071     int pes_payload_size;
00072 
00073     int transport_stream_id;
00074     int original_network_id;
00075     int service_id;
00076 
00077     int pmt_start_pid;
00078     int start_pid;
00079 } MpegTSWrite;
00080 
00081 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
00082 #define DEFAULT_PES_HEADER_FREQ 16
00083 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
00084 
00085 static const AVOption options[] = {
00086     { "mpegts_transport_stream_id", "Set transport_stream_id field.",
00087       offsetof(MpegTSWrite, transport_stream_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
00088     { "mpegts_original_network_id", "Set original_network_id field.",
00089       offsetof(MpegTSWrite, original_network_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
00090     { "mpegts_service_id", "Set service_id field.",
00091       offsetof(MpegTSWrite, service_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
00092     { "mpegts_pmt_start_pid", "Set the first pid of the PMT.",
00093       offsetof(MpegTSWrite, pmt_start_pid), AV_OPT_TYPE_INT, {.dbl = 0x1000 }, 0x1000, 0x1f00, AV_OPT_FLAG_ENCODING_PARAM},
00094     { "mpegts_start_pid", "Set the first pid.",
00095       offsetof(MpegTSWrite, start_pid), AV_OPT_TYPE_INT, {.dbl = 0x0100 }, 0x0100, 0x0f00, AV_OPT_FLAG_ENCODING_PARAM},
00096     { "muxrate", NULL, offsetof(MpegTSWrite, mux_rate), AV_OPT_TYPE_INT, {1}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
00097     { "pes_payload_size", "Minimum PES packet payload in bytes",
00098       offsetof(MpegTSWrite, pes_payload_size), AV_OPT_TYPE_INT, {DEFAULT_PES_PAYLOAD_SIZE}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
00099     { NULL },
00100 };
00101 
00102 static const AVClass mpegts_muxer_class = {
00103     .class_name     = "MPEGTS muxer",
00104     .item_name      = av_default_item_name,
00105     .option         = options,
00106     .version        = LIBAVUTIL_VERSION_INT,
00107 };
00108 
00109 /* The section length is 12 bits. The first 2 are set to 0, the remaining
00110  * 10 bits should not exceed 1021. */
00111 #define SECTION_LENGTH 1020
00112 
00113 /* NOTE: 4 bytes must be left at the end for the crc32 */
00114 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
00115 {
00116     unsigned int crc;
00117     unsigned char packet[TS_PACKET_SIZE];
00118     const unsigned char *buf_ptr;
00119     unsigned char *q;
00120     int first, b, len1, left;
00121 
00122     crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
00123     buf[len - 4] = (crc >> 24) & 0xff;
00124     buf[len - 3] = (crc >> 16) & 0xff;
00125     buf[len - 2] = (crc >> 8) & 0xff;
00126     buf[len - 1] = (crc) & 0xff;
00127 
00128     /* send each packet */
00129     buf_ptr = buf;
00130     while (len > 0) {
00131         first = (buf == buf_ptr);
00132         q = packet;
00133         *q++ = 0x47;
00134         b = (s->pid >> 8);
00135         if (first)
00136             b |= 0x40;
00137         *q++ = b;
00138         *q++ = s->pid;
00139         s->cc = (s->cc + 1) & 0xf;
00140         *q++ = 0x10 | s->cc;
00141         if (first)
00142             *q++ = 0; /* 0 offset */
00143         len1 = TS_PACKET_SIZE - (q - packet);
00144         if (len1 > len)
00145             len1 = len;
00146         memcpy(q, buf_ptr, len1);
00147         q += len1;
00148         /* add known padding data */
00149         left = TS_PACKET_SIZE - (q - packet);
00150         if (left > 0)
00151             memset(q, 0xff, left);
00152 
00153         s->write_packet(s, packet);
00154 
00155         buf_ptr += len1;
00156         len -= len1;
00157     }
00158 }
00159 
00160 static inline void put16(uint8_t **q_ptr, int val)
00161 {
00162     uint8_t *q;
00163     q = *q_ptr;
00164     *q++ = val >> 8;
00165     *q++ = val;
00166     *q_ptr = q;
00167 }
00168 
00169 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
00170                           int version, int sec_num, int last_sec_num,
00171                           uint8_t *buf, int len)
00172 {
00173     uint8_t section[1024], *q;
00174     unsigned int tot_len;
00175     /* reserved_future_use field must be set to 1 for SDT */
00176     unsigned int flags = tid == SDT_TID ? 0xf000 : 0xb000;
00177 
00178     tot_len = 3 + 5 + len + 4;
00179     /* check if not too big */
00180     if (tot_len > 1024)
00181         return -1;
00182 
00183     q = section;
00184     *q++ = tid;
00185     put16(&q, flags | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
00186     put16(&q, id);
00187     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
00188     *q++ = sec_num;
00189     *q++ = last_sec_num;
00190     memcpy(q, buf, len);
00191 
00192     mpegts_write_section(s, section, tot_len);
00193     return 0;
00194 }
00195 
00196 /*********************************************/
00197 /* mpegts writer */
00198 
00199 #define DEFAULT_PROVIDER_NAME   "Libav"
00200 #define DEFAULT_SERVICE_NAME    "Service01"
00201 
00202 /* we retransmit the SI info at this rate */
00203 #define SDT_RETRANS_TIME 500
00204 #define PAT_RETRANS_TIME 100
00205 #define PCR_RETRANS_TIME 20
00206 
00207 typedef struct MpegTSWriteStream {
00208     struct MpegTSService *service;
00209     int pid; /* stream associated pid */
00210     int cc;
00211     int payload_size;
00212     int first_pts_check; 
00213     int64_t payload_pts;
00214     int64_t payload_dts;
00215     int payload_flags;
00216     uint8_t *payload;
00217     ADTSContext *adts;
00218 } MpegTSWriteStream;
00219 
00220 static void mpegts_write_pat(AVFormatContext *s)
00221 {
00222     MpegTSWrite *ts = s->priv_data;
00223     MpegTSService *service;
00224     uint8_t data[SECTION_LENGTH], *q;
00225     int i;
00226 
00227     q = data;
00228     for(i = 0; i < ts->nb_services; i++) {
00229         service = ts->services[i];
00230         put16(&q, service->sid);
00231         put16(&q, 0xe000 | service->pmt.pid);
00232     }
00233     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
00234                           data, q - data);
00235 }
00236 
00237 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
00238 {
00239     uint8_t data[SECTION_LENGTH], *q, *desc_length_ptr, *program_info_length_ptr;
00240     int val, stream_type, i, err = 0;
00241 
00242     q = data;
00243     put16(&q, 0xe000 | service->pcr_pid);
00244 
00245     program_info_length_ptr = q;
00246     q += 2; /* patched after */
00247 
00248     /* put program info here */
00249 
00250     val = 0xf000 | (q - program_info_length_ptr - 2);
00251     program_info_length_ptr[0] = val >> 8;
00252     program_info_length_ptr[1] = val;
00253 
00254     for(i = 0; i < s->nb_streams; i++) {
00255         AVStream *st = s->streams[i];
00256         MpegTSWriteStream *ts_st = st->priv_data;
00257         AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,0);
00258 
00259         if (q - data > SECTION_LENGTH - 3 - 2 - 6) {
00260             err = 1;
00261             break;
00262         }
00263         switch(st->codec->codec_id) {
00264         case CODEC_ID_MPEG1VIDEO:
00265         case CODEC_ID_MPEG2VIDEO:
00266             stream_type = STREAM_TYPE_VIDEO_MPEG2;
00267             break;
00268         case CODEC_ID_MPEG4:
00269             stream_type = STREAM_TYPE_VIDEO_MPEG4;
00270             break;
00271         case CODEC_ID_H264:
00272             stream_type = STREAM_TYPE_VIDEO_H264;
00273             break;
00274         case CODEC_ID_DIRAC:
00275             stream_type = STREAM_TYPE_VIDEO_DIRAC;
00276             break;
00277         case CODEC_ID_MP2:
00278         case CODEC_ID_MP3:
00279             stream_type = STREAM_TYPE_AUDIO_MPEG1;
00280             break;
00281         case CODEC_ID_AAC:
00282             stream_type = STREAM_TYPE_AUDIO_AAC;
00283             break;
00284         case CODEC_ID_AAC_LATM:
00285             stream_type = STREAM_TYPE_AUDIO_AAC_LATM;
00286             break;
00287         case CODEC_ID_AC3:
00288             stream_type = STREAM_TYPE_AUDIO_AC3;
00289             break;
00290         default:
00291             stream_type = STREAM_TYPE_PRIVATE_DATA;
00292             break;
00293         }
00294         *q++ = stream_type;
00295         put16(&q, 0xe000 | ts_st->pid);
00296         desc_length_ptr = q;
00297         q += 2; /* patched after */
00298 
00299         /* write optional descriptors here */
00300         switch(st->codec->codec_type) {
00301         case AVMEDIA_TYPE_AUDIO:
00302             if (lang) {
00303                 char *p;
00304                 char *next = lang->value;
00305                 uint8_t *len_ptr;
00306 
00307                 *q++ = 0x0a; /* ISO 639 language descriptor */
00308                 len_ptr = q++;
00309                 *len_ptr = 0;
00310 
00311                 for (p = lang->value; next && *len_ptr < 255 / 4 * 4; p = next + 1) {
00312                     if (q - data > SECTION_LENGTH - 4) {
00313                         err = 1;
00314                         break;
00315                     }
00316                     next = strchr(p, ',');
00317                     if (strlen(p) != 3 && (!next || next != p + 3))
00318                         continue; /* not a 3-letter code */
00319 
00320                     *q++ = *p++;
00321                     *q++ = *p++;
00322                     *q++ = *p++;
00323 
00324                 if (st->disposition & AV_DISPOSITION_CLEAN_EFFECTS)
00325                     *q++ = 0x01;
00326                 else if (st->disposition & AV_DISPOSITION_HEARING_IMPAIRED)
00327                     *q++ = 0x02;
00328                 else if (st->disposition & AV_DISPOSITION_VISUAL_IMPAIRED)
00329                     *q++ = 0x03;
00330                 else
00331                     *q++ = 0; /* undefined type */
00332 
00333                     *len_ptr += 4;
00334                 }
00335 
00336                 if (*len_ptr == 0)
00337                     q -= 2; /* no language codes were written */
00338             }
00339             break;
00340         case AVMEDIA_TYPE_SUBTITLE:
00341             {
00342                 const char *language;
00343                 language = lang && strlen(lang->value)==3 ? lang->value : "eng";
00344                 *q++ = 0x59;
00345                 *q++ = 8;
00346                 *q++ = language[0];
00347                 *q++ = language[1];
00348                 *q++ = language[2];
00349                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
00350 
00351                 if (q - data > SECTION_LENGTH - 4) {
00352                     err = 1;
00353                     break;
00354                 }
00355                 if(st->codec->extradata_size == 4) {
00356                     memcpy(q, st->codec->extradata, 4);
00357                     q += 4;
00358                 } else {
00359                     put16(&q, 1); /* page id */
00360                     put16(&q, 1); /* ancillary page id */
00361                 }
00362             }
00363             break;
00364         case AVMEDIA_TYPE_VIDEO:
00365             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
00366                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
00367                 *q++ = 4;
00368                 *q++ = 'd';
00369                 *q++ = 'r';
00370                 *q++ = 'a';
00371                 *q++ = 'c';
00372             }
00373             break;
00374         }
00375 
00376         val = 0xf000 | (q - desc_length_ptr - 2);
00377         desc_length_ptr[0] = val >> 8;
00378         desc_length_ptr[1] = val;
00379     }
00380 
00381     if (err)
00382         av_log(s, AV_LOG_ERROR,
00383                "The PMT section is too small for stream %d and following.\n"
00384                "Try reducing the number of languages in the audio streams "
00385                "or the total number of streams.\n",
00386                i);
00387 
00388     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
00389                           data, q - data);
00390 }
00391 
00392 /* NOTE: str == NULL is accepted for an empty string */
00393 static void putstr8(uint8_t **q_ptr, const char *str)
00394 {
00395     uint8_t *q;
00396     int len;
00397 
00398     q = *q_ptr;
00399     if (!str)
00400         len = 0;
00401     else
00402         len = strlen(str);
00403     *q++ = len;
00404     memcpy(q, str, len);
00405     q += len;
00406     *q_ptr = q;
00407 }
00408 
00409 static void mpegts_write_sdt(AVFormatContext *s)
00410 {
00411     MpegTSWrite *ts = s->priv_data;
00412     MpegTSService *service;
00413     uint8_t data[SECTION_LENGTH], *q, *desc_list_len_ptr, *desc_len_ptr;
00414     int i, running_status, free_ca_mode, val;
00415 
00416     q = data;
00417     put16(&q, ts->onid);
00418     *q++ = 0xff;
00419     for(i = 0; i < ts->nb_services; i++) {
00420         service = ts->services[i];
00421         put16(&q, service->sid);
00422         *q++ = 0xfc | 0x00; /* currently no EIT info */
00423         desc_list_len_ptr = q;
00424         q += 2;
00425         running_status = 4; /* running */
00426         free_ca_mode = 0;
00427 
00428         /* write only one descriptor for the service name and provider */
00429         *q++ = 0x48;
00430         desc_len_ptr = q;
00431         q++;
00432         *q++ = 0x01; /* digital television service */
00433         putstr8(&q, service->provider_name);
00434         putstr8(&q, service->name);
00435         desc_len_ptr[0] = q - desc_len_ptr - 1;
00436 
00437         /* fill descriptor length */
00438         val = (running_status << 13) | (free_ca_mode << 12) |
00439             (q - desc_list_len_ptr - 2);
00440         desc_list_len_ptr[0] = val >> 8;
00441         desc_list_len_ptr[1] = val;
00442     }
00443     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
00444                           data, q - data);
00445 }
00446 
00447 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
00448                                          int sid,
00449                                          const char *provider_name,
00450                                          const char *name)
00451 {
00452     MpegTSService *service;
00453 
00454     service = av_mallocz(sizeof(MpegTSService));
00455     if (!service)
00456         return NULL;
00457     service->pmt.pid = ts->pmt_start_pid + ts->nb_services;
00458     service->sid = sid;
00459     service->provider_name = av_strdup(provider_name);
00460     service->name = av_strdup(name);
00461     service->pcr_pid = 0x1fff;
00462     dynarray_add(&ts->services, &ts->nb_services, service);
00463     return service;
00464 }
00465 
00466 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
00467 {
00468     AVFormatContext *ctx = s->opaque;
00469     avio_write(ctx->pb, packet, TS_PACKET_SIZE);
00470 }
00471 
00472 static int mpegts_write_header(AVFormatContext *s)
00473 {
00474     MpegTSWrite *ts = s->priv_data;
00475     MpegTSWriteStream *ts_st;
00476     MpegTSService *service;
00477     AVStream *st, *pcr_st = NULL;
00478     AVDictionaryEntry *title, *provider;
00479     int i, j;
00480     const char *service_name;
00481     const char *provider_name;
00482     int *pids;
00483 
00484     // round up to a whole number of TS packets
00485     ts->pes_payload_size = (ts->pes_payload_size + 14 + 183) / 184 * 184 - 14;
00486 
00487     ts->tsid = ts->transport_stream_id;
00488     ts->onid = ts->original_network_id;
00489     /* allocate a single DVB service */
00490     title = av_dict_get(s->metadata, "service_name", NULL, 0);
00491     if (!title)
00492         title = av_dict_get(s->metadata, "title", NULL, 0);
00493     service_name = title ? title->value : DEFAULT_SERVICE_NAME;
00494     provider = av_dict_get(s->metadata, "service_provider", NULL, 0);
00495     provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;
00496     service = mpegts_add_service(ts, ts->service_id, provider_name, service_name);
00497     service->pmt.write_packet = section_write_packet;
00498     service->pmt.opaque = s;
00499     service->pmt.cc = 15;
00500 
00501     ts->pat.pid = PAT_PID;
00502     ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write
00503     ts->pat.write_packet = section_write_packet;
00504     ts->pat.opaque = s;
00505 
00506     ts->sdt.pid = SDT_PID;
00507     ts->sdt.cc = 15;
00508     ts->sdt.write_packet = section_write_packet;
00509     ts->sdt.opaque = s;
00510 
00511     pids = av_malloc(s->nb_streams * sizeof(*pids));
00512     if (!pids)
00513         return AVERROR(ENOMEM);
00514 
00515     /* assign pids to each stream */
00516     for(i = 0;i < s->nb_streams; i++) {
00517         st = s->streams[i];
00518         avpriv_set_pts_info(st, 33, 1, 90000);
00519         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
00520         if (!ts_st)
00521             goto fail;
00522         st->priv_data = ts_st;
00523         ts_st->payload = av_mallocz(ts->pes_payload_size);
00524         if (!ts_st->payload)
00525             goto fail;
00526         ts_st->service = service;
00527         /* MPEG pid values < 16 are reserved. Applications which set st->id in
00528          * this range are assigned a calculated pid. */
00529         if (st->id < 16) {
00530             ts_st->pid = ts->start_pid + i;
00531         } else if (st->id < 0x1FFF) {
00532             ts_st->pid = st->id;
00533         } else {
00534             av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);
00535             goto fail;
00536         }
00537         if (ts_st->pid == service->pmt.pid) {
00538             av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
00539             goto fail;
00540         }
00541         for (j = 0; j < i; j++)
00542             if (pids[j] == ts_st->pid) {
00543                 av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
00544                 goto fail;
00545             }
00546         pids[i] = ts_st->pid;
00547         ts_st->payload_pts = AV_NOPTS_VALUE;
00548         ts_st->payload_dts = AV_NOPTS_VALUE;
00549         ts_st->first_pts_check = 1;
00550         ts_st->cc = 15;
00551         /* update PCR pid by using the first video stream */
00552         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
00553             service->pcr_pid == 0x1fff) {
00554             service->pcr_pid = ts_st->pid;
00555             pcr_st = st;
00556         }
00557         if (st->codec->codec_id == CODEC_ID_AAC &&
00558             st->codec->extradata_size > 0) {
00559             ts_st->adts = av_mallocz(sizeof(*ts_st->adts));
00560             if (!ts_st->adts)
00561                 goto fail;
00562             if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,
00563                                          st->codec->extradata_size) < 0)
00564                 goto fail;
00565         }
00566     }
00567 
00568     av_free(pids);
00569 
00570     /* if no video stream, use the first stream as PCR */
00571     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
00572         pcr_st = s->streams[0];
00573         ts_st = pcr_st->priv_data;
00574         service->pcr_pid = ts_st->pid;
00575     }
00576 
00577 #if FF_API_MUXRATE
00578     if (s->mux_rate)
00579         ts->mux_rate = s->mux_rate;
00580 #endif
00581 
00582     if (ts->mux_rate > 1) {
00583         service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
00584             (TS_PACKET_SIZE * 8 * 1000);
00585         ts->sdt_packet_period      = (ts->mux_rate * SDT_RETRANS_TIME) /
00586             (TS_PACKET_SIZE * 8 * 1000);
00587         ts->pat_packet_period      = (ts->mux_rate * PAT_RETRANS_TIME) /
00588             (TS_PACKET_SIZE * 8 * 1000);
00589 
00590         ts->first_pcr = av_rescale(s->max_delay, PCR_TIME_BASE, AV_TIME_BASE);
00591     } else {
00592         /* Arbitrary values, PAT/PMT could be written on key frames */
00593         ts->sdt_packet_period = 200;
00594         ts->pat_packet_period = 40;
00595         if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00596             if (!pcr_st->codec->frame_size) {
00597                 av_log(s, AV_LOG_WARNING, "frame size not set\n");
00598                 service->pcr_packet_period =
00599                     pcr_st->codec->sample_rate/(10*512);
00600             } else {
00601                 service->pcr_packet_period =
00602                     pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
00603             }
00604         } else {
00605             // max delta PCR 0.1s
00606             service->pcr_packet_period =
00607                 pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
00608         }
00609     }
00610 
00611     // output a PCR as soon as possible
00612     service->pcr_packet_count = service->pcr_packet_period;
00613     ts->pat_packet_count = ts->pat_packet_period-1;
00614     ts->sdt_packet_count = ts->sdt_packet_period-1;
00615 
00616     if (ts->mux_rate == 1)
00617         av_log(s, AV_LOG_INFO, "muxrate VBR, ");
00618     else
00619         av_log(s, AV_LOG_INFO, "muxrate %d, ", ts->mux_rate);
00620     av_log(s, AV_LOG_INFO, "pcr every %d pkts, "
00621            "sdt every %d, pat/pmt every %d pkts\n",
00622            service->pcr_packet_period,
00623            ts->sdt_packet_period, ts->pat_packet_period);
00624 
00625     avio_flush(s->pb);
00626 
00627     return 0;
00628 
00629  fail:
00630     av_free(pids);
00631     for(i = 0;i < s->nb_streams; i++) {
00632         MpegTSWriteStream *ts_st;
00633         st = s->streams[i];
00634         ts_st = st->priv_data;
00635         if (ts_st) {
00636             av_freep(&ts_st->payload);
00637             av_freep(&ts_st->adts);
00638         }
00639         av_freep(&st->priv_data);
00640     }
00641     return -1;
00642 }
00643 
00644 /* send SDT, PAT and PMT tables regulary */
00645 static void retransmit_si_info(AVFormatContext *s)
00646 {
00647     MpegTSWrite *ts = s->priv_data;
00648     int i;
00649 
00650     if (++ts->sdt_packet_count == ts->sdt_packet_period) {
00651         ts->sdt_packet_count = 0;
00652         mpegts_write_sdt(s);
00653     }
00654     if (++ts->pat_packet_count == ts->pat_packet_period) {
00655         ts->pat_packet_count = 0;
00656         mpegts_write_pat(s);
00657         for(i = 0; i < ts->nb_services; i++) {
00658             mpegts_write_pmt(s, ts->services[i]);
00659         }
00660     }
00661 }
00662 
00663 static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
00664 {
00665     return av_rescale(avio_tell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +
00666            ts->first_pcr;
00667 }
00668 
00669 static int write_pcr_bits(uint8_t *buf, int64_t pcr)
00670 {
00671     int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;
00672 
00673     *buf++ = pcr_high >> 25;
00674     *buf++ = pcr_high >> 17;
00675     *buf++ = pcr_high >> 9;
00676     *buf++ = pcr_high >> 1;
00677     *buf++ = pcr_high << 7 | pcr_low >> 8 | 0x7e;
00678     *buf++ = pcr_low;
00679 
00680     return 6;
00681 }
00682 
00683 /* Write a single null transport stream packet */
00684 static void mpegts_insert_null_packet(AVFormatContext *s)
00685 {
00686     uint8_t *q;
00687     uint8_t buf[TS_PACKET_SIZE];
00688 
00689     q = buf;
00690     *q++ = 0x47;
00691     *q++ = 0x00 | 0x1f;
00692     *q++ = 0xff;
00693     *q++ = 0x10;
00694     memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));
00695     avio_write(s->pb, buf, TS_PACKET_SIZE);
00696 }
00697 
00698 /* Write a single transport stream packet with a PCR and no payload */
00699 static void mpegts_insert_pcr_only(AVFormatContext *s, AVStream *st)
00700 {
00701     MpegTSWrite *ts = s->priv_data;
00702     MpegTSWriteStream *ts_st = st->priv_data;
00703     uint8_t *q;
00704     uint8_t buf[TS_PACKET_SIZE];
00705 
00706     q = buf;
00707     *q++ = 0x47;
00708     *q++ = ts_st->pid >> 8;
00709     *q++ = ts_st->pid;
00710     *q++ = 0x20 | ts_st->cc;   /* Adaptation only */
00711     /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
00712     *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
00713     *q++ = 0x10;               /* Adaptation flags: PCR present */
00714 
00715     /* PCR coded into 6 bytes */
00716     q += write_pcr_bits(q, get_pcr(ts, s->pb));
00717 
00718     /* stuffing bytes */
00719     memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));
00720     avio_write(s->pb, buf, TS_PACKET_SIZE);
00721 }
00722 
00723 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
00724 {
00725     int val;
00726 
00727     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
00728     *q++ = val;
00729     val = (((pts >> 15) & 0x7fff) << 1) | 1;
00730     *q++ = val >> 8;
00731     *q++ = val;
00732     val = (((pts) & 0x7fff) << 1) | 1;
00733     *q++ = val >> 8;
00734     *q++ = val;
00735 }
00736 
00737 /* Set an adaptation field flag in an MPEG-TS packet*/
00738 static void set_af_flag(uint8_t *pkt, int flag)
00739 {
00740     // expect at least one flag to set
00741     assert(flag);
00742 
00743     if ((pkt[3] & 0x20) == 0) {
00744         // no AF yet, set adaptation field flag
00745         pkt[3] |= 0x20;
00746         // 1 byte length, no flags
00747         pkt[4] = 1;
00748         pkt[5] = 0;
00749     }
00750     pkt[5] |= flag;
00751 }
00752 
00753 /* Extend the adaptation field by size bytes */
00754 static void extend_af(uint8_t *pkt, int size)
00755 {
00756     // expect already existing adaptation field
00757     assert(pkt[3] & 0x20);
00758     pkt[4] += size;
00759 }
00760 
00761 /* Get a pointer to MPEG-TS payload (right after TS packet header) */
00762 static uint8_t *get_ts_payload_start(uint8_t *pkt)
00763 {
00764     if (pkt[3] & 0x20)
00765         return pkt + 5 + pkt[4];
00766     else
00767         return pkt + 4;
00768 }
00769 
00770 /* Add a pes header to the front of payload, and segment into an integer number of
00771  * ts packets. The final ts packet is padded using an over-sized adaptation header
00772  * to exactly fill the last ts packet.
00773  * NOTE: 'payload' contains a complete PES payload.
00774  */
00775 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
00776                              const uint8_t *payload, int payload_size,
00777                              int64_t pts, int64_t dts, int key)
00778 {
00779     MpegTSWriteStream *ts_st = st->priv_data;
00780     MpegTSWrite *ts = s->priv_data;
00781     uint8_t buf[TS_PACKET_SIZE];
00782     uint8_t *q;
00783     int val, is_start, len, header_len, write_pcr, private_code, flags;
00784     int afc_len, stuffing_len;
00785     int64_t pcr = -1; /* avoid warning */
00786     int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
00787 
00788     is_start = 1;
00789     while (payload_size > 0) {
00790         retransmit_si_info(s);
00791 
00792         write_pcr = 0;
00793         if (ts_st->pid == ts_st->service->pcr_pid) {
00794             if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
00795                 ts_st->service->pcr_packet_count++;
00796             if (ts_st->service->pcr_packet_count >=
00797                 ts_st->service->pcr_packet_period) {
00798                 ts_st->service->pcr_packet_count = 0;
00799                 write_pcr = 1;
00800             }
00801         }
00802 
00803         if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&
00804             (dts - get_pcr(ts, s->pb)/300) > delay) {
00805             /* pcr insert gets priority over null packet insert */
00806             if (write_pcr)
00807                 mpegts_insert_pcr_only(s, st);
00808             else
00809                 mpegts_insert_null_packet(s);
00810             continue; /* recalculate write_pcr and possibly retransmit si_info */
00811         }
00812 
00813         /* prepare packet header */
00814         q = buf;
00815         *q++ = 0x47;
00816         val = (ts_st->pid >> 8);
00817         if (is_start)
00818             val |= 0x40;
00819         *q++ = val;
00820         *q++ = ts_st->pid;
00821         ts_st->cc = (ts_st->cc + 1) & 0xf;
00822         *q++ = 0x10 | ts_st->cc; // payload indicator + CC
00823         if (key && is_start && pts != AV_NOPTS_VALUE) {
00824             // set Random Access for key frames
00825             if (ts_st->pid == ts_st->service->pcr_pid)
00826                 write_pcr = 1;
00827             set_af_flag(buf, 0x40);
00828             q = get_ts_payload_start(buf);
00829         }
00830         if (write_pcr) {
00831             set_af_flag(buf, 0x10);
00832             q = get_ts_payload_start(buf);
00833             // add 11, pcr references the last byte of program clock reference base
00834             if (ts->mux_rate > 1)
00835                 pcr = get_pcr(ts, s->pb);
00836             else
00837                 pcr = (dts - delay)*300;
00838             if (dts != AV_NOPTS_VALUE && dts < pcr / 300)
00839                 av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
00840             extend_af(buf, write_pcr_bits(q, pcr));
00841             q = get_ts_payload_start(buf);
00842         }
00843         if (is_start) {
00844             int pes_extension = 0;
00845             /* write PES header */
00846             *q++ = 0x00;
00847             *q++ = 0x00;
00848             *q++ = 0x01;
00849             private_code = 0;
00850             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00851                 if (st->codec->codec_id == CODEC_ID_DIRAC) {
00852                     *q++ = 0xfd;
00853                 } else
00854                     *q++ = 0xe0;
00855             } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
00856                        (st->codec->codec_id == CODEC_ID_MP2 ||
00857                         st->codec->codec_id == CODEC_ID_MP3 ||
00858                         st->codec->codec_id == CODEC_ID_AAC)) {
00859                 *q++ = 0xc0;
00860             } else {
00861                 *q++ = 0xbd;
00862                 if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
00863                     private_code = 0x20;
00864                 }
00865             }
00866             header_len = 0;
00867             flags = 0;
00868             if (pts != AV_NOPTS_VALUE) {
00869                 header_len += 5;
00870                 flags |= 0x80;
00871             }
00872             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
00873                 header_len += 5;
00874                 flags |= 0x40;
00875             }
00876             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
00877                 st->codec->codec_id == CODEC_ID_DIRAC) {
00878                 /* set PES_extension_flag */
00879                 pes_extension = 1;
00880                 flags |= 0x01;
00881 
00882                 /*
00883                 * One byte for PES2 extension flag +
00884                 * one byte for extension length +
00885                 * one byte for extension id
00886                 */
00887                 header_len += 3;
00888             }
00889             len = payload_size + header_len + 3;
00890             if (private_code != 0)
00891                 len++;
00892             if (len > 0xffff)
00893                 len = 0;
00894             *q++ = len >> 8;
00895             *q++ = len;
00896             val = 0x80;
00897             /* data alignment indicator is required for subtitle data */
00898             if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE)
00899                 val |= 0x04;
00900             *q++ = val;
00901             *q++ = flags;
00902             *q++ = header_len;
00903             if (pts != AV_NOPTS_VALUE) {
00904                 write_pts(q, flags >> 6, pts);
00905                 q += 5;
00906             }
00907             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
00908                 write_pts(q, 1, dts);
00909                 q += 5;
00910             }
00911             if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
00912                 flags = 0x01;  /* set PES_extension_flag_2 */
00913                 *q++ = flags;
00914                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
00915                 /*
00916                 * Set the stream id extension flag bit to 0 and
00917                 * write the extended stream id
00918                 */
00919                 *q++ = 0x00 | 0x60;
00920             }
00921             if (private_code != 0)
00922                 *q++ = private_code;
00923             is_start = 0;
00924         }
00925         /* header size */
00926         header_len = q - buf;
00927         /* data len */
00928         len = TS_PACKET_SIZE - header_len;
00929         if (len > payload_size)
00930             len = payload_size;
00931         stuffing_len = TS_PACKET_SIZE - header_len - len;
00932         if (stuffing_len > 0) {
00933             /* add stuffing with AFC */
00934             if (buf[3] & 0x20) {
00935                 /* stuffing already present: increase its size */
00936                 afc_len = buf[4] + 1;
00937                 memmove(buf + 4 + afc_len + stuffing_len,
00938                         buf + 4 + afc_len,
00939                         header_len - (4 + afc_len));
00940                 buf[4] += stuffing_len;
00941                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
00942             } else {
00943                 /* add stuffing */
00944                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
00945                 buf[3] |= 0x20;
00946                 buf[4] = stuffing_len - 1;
00947                 if (stuffing_len >= 2) {
00948                     buf[5] = 0x00;
00949                     memset(buf + 6, 0xff, stuffing_len - 2);
00950                 }
00951             }
00952         }
00953         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
00954         payload += len;
00955         payload_size -= len;
00956         avio_write(s->pb, buf, TS_PACKET_SIZE);
00957     }
00958     avio_flush(s->pb);
00959 }
00960 
00961 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
00962 {
00963     AVStream *st = s->streams[pkt->stream_index];
00964     int size = pkt->size;
00965     uint8_t *buf= pkt->data;
00966     uint8_t *data= NULL;
00967     MpegTSWrite *ts = s->priv_data;
00968     MpegTSWriteStream *ts_st = st->priv_data;
00969     const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;
00970     int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
00971 
00972     if (pkt->pts != AV_NOPTS_VALUE)
00973         pts = pkt->pts + delay;
00974     if (pkt->dts != AV_NOPTS_VALUE)
00975         dts = pkt->dts + delay;
00976 
00977     if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {
00978         av_log(s, AV_LOG_ERROR, "first pts value must set\n");
00979         return -1;
00980     }
00981     ts_st->first_pts_check = 0;
00982 
00983     if (st->codec->codec_id == CODEC_ID_H264) {
00984         const uint8_t *p = buf, *buf_end = p+size;
00985         uint32_t state = -1;
00986 
00987         if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
00988             av_log(s, AV_LOG_ERROR, "H.264 bitstream malformed, "
00989                    "no startcode found, use -vbsf h264_mp4toannexb\n");
00990             return -1;
00991         }
00992 
00993         do {
00994             p = avpriv_mpv_find_start_code(p, buf_end, &state);
00995             //av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);
00996         } while (p < buf_end && (state & 0x1f) != 9 &&
00997                  (state & 0x1f) != 5 && (state & 0x1f) != 1);
00998 
00999         if ((state & 0x1f) != 9) { // AUD NAL
01000             data = av_malloc(pkt->size+6);
01001             if (!data)
01002                 return -1;
01003             memcpy(data+6, pkt->data, pkt->size);
01004             AV_WB32(data, 0x00000001);
01005             data[4] = 0x09;
01006             data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bit
01007             buf  = data;
01008             size = pkt->size+6;
01009         }
01010     } else if (st->codec->codec_id == CODEC_ID_AAC) {
01011         if (pkt->size < 2)
01012             return -1;
01013         if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {
01014             ADTSContext *adts = ts_st->adts;
01015             int new_size, err;
01016             if (!adts) {
01017                 av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format "
01018                        "and extradata missing\n");
01019                 return -1;
01020             }
01021             new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;
01022             if ((unsigned)new_size >= INT_MAX)
01023                 return -1;
01024             data = av_malloc(new_size);
01025             if (!data)
01026                 return AVERROR(ENOMEM);
01027             err = ff_adts_write_frame_header(adts, data, pkt->size,
01028                                              adts->pce_size);
01029             if (err < 0) {
01030                 av_free(data);
01031                 return err;
01032             }
01033             if (adts->pce_size) {
01034                 memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);
01035                 adts->pce_size = 0;
01036             }
01037             memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);
01038             buf = data;
01039             size = new_size;
01040         }
01041     }
01042 
01043     if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {
01044         // for video and subtitle, write a single pes packet
01045         mpegts_write_pes(s, st, buf, size, pts, dts, pkt->flags & AV_PKT_FLAG_KEY);
01046         av_free(data);
01047         return 0;
01048     }
01049 
01050     if (ts_st->payload_size + size > ts->pes_payload_size) {
01051         if (ts_st->payload_size) {
01052             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
01053                              ts_st->payload_pts, ts_st->payload_dts,
01054                              ts_st->payload_flags & AV_PKT_FLAG_KEY);
01055             ts_st->payload_size = 0;
01056         }
01057         if (size > ts->pes_payload_size) {
01058             mpegts_write_pes(s, st, buf, size, pts, dts,
01059                              pkt->flags & AV_PKT_FLAG_KEY);
01060             av_free(data);
01061             return 0;
01062         }
01063     }
01064 
01065     if (!ts_st->payload_size) {
01066         ts_st->payload_pts = pts;
01067         ts_st->payload_dts = dts;
01068         ts_st->payload_flags = pkt->flags;
01069     }
01070 
01071     memcpy(ts_st->payload + ts_st->payload_size, buf, size);
01072     ts_st->payload_size += size;
01073 
01074     av_free(data);
01075 
01076     return 0;
01077 }
01078 
01079 static int mpegts_write_end(AVFormatContext *s)
01080 {
01081     MpegTSWrite *ts = s->priv_data;
01082     MpegTSWriteStream *ts_st;
01083     MpegTSService *service;
01084     AVStream *st;
01085     int i;
01086 
01087     /* flush current packets */
01088     for(i = 0; i < s->nb_streams; i++) {
01089         st = s->streams[i];
01090         ts_st = st->priv_data;
01091         if (ts_st->payload_size > 0) {
01092             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
01093                              ts_st->payload_pts, ts_st->payload_dts,
01094                              ts_st->payload_flags & AV_PKT_FLAG_KEY);
01095         }
01096         av_freep(&ts_st->payload);
01097         av_freep(&ts_st->adts);
01098     }
01099     avio_flush(s->pb);
01100 
01101     for(i = 0; i < ts->nb_services; i++) {
01102         service = ts->services[i];
01103         av_freep(&service->provider_name);
01104         av_freep(&service->name);
01105         av_free(service);
01106     }
01107     av_free(ts->services);
01108 
01109     return 0;
01110 }
01111 
01112 AVOutputFormat ff_mpegts_muxer = {
01113     .name              = "mpegts",
01114     .long_name         = NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
01115     .mime_type         = "video/x-mpegts",
01116     .extensions        = "ts,m2t",
01117     .priv_data_size    = sizeof(MpegTSWrite),
01118     .audio_codec       = CODEC_ID_MP2,
01119     .video_codec       = CODEC_ID_MPEG2VIDEO,
01120     .write_header      = mpegts_write_header,
01121     .write_packet      = mpegts_write_packet,
01122     .write_trailer     = mpegts_write_end,
01123     .priv_class = &mpegts_muxer_class,
01124 };