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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 /* NOTE: 4 bytes must be left at the end for the crc32 */
00110 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
00111 {
00112     unsigned int crc;
00113     unsigned char packet[TS_PACKET_SIZE];
00114     const unsigned char *buf_ptr;
00115     unsigned char *q;
00116     int first, b, len1, left;
00117 
00118     crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
00119     buf[len - 4] = (crc >> 24) & 0xff;
00120     buf[len - 3] = (crc >> 16) & 0xff;
00121     buf[len - 2] = (crc >> 8) & 0xff;
00122     buf[len - 1] = (crc) & 0xff;
00123 
00124     /* send each packet */
00125     buf_ptr = buf;
00126     while (len > 0) {
00127         first = (buf == buf_ptr);
00128         q = packet;
00129         *q++ = 0x47;
00130         b = (s->pid >> 8);
00131         if (first)
00132             b |= 0x40;
00133         *q++ = b;
00134         *q++ = s->pid;
00135         s->cc = (s->cc + 1) & 0xf;
00136         *q++ = 0x10 | s->cc;
00137         if (first)
00138             *q++ = 0; /* 0 offset */
00139         len1 = TS_PACKET_SIZE - (q - packet);
00140         if (len1 > len)
00141             len1 = len;
00142         memcpy(q, buf_ptr, len1);
00143         q += len1;
00144         /* add known padding data */
00145         left = TS_PACKET_SIZE - (q - packet);
00146         if (left > 0)
00147             memset(q, 0xff, left);
00148 
00149         s->write_packet(s, packet);
00150 
00151         buf_ptr += len1;
00152         len -= len1;
00153     }
00154 }
00155 
00156 static inline void put16(uint8_t **q_ptr, int val)
00157 {
00158     uint8_t *q;
00159     q = *q_ptr;
00160     *q++ = val >> 8;
00161     *q++ = val;
00162     *q_ptr = q;
00163 }
00164 
00165 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
00166                           int version, int sec_num, int last_sec_num,
00167                           uint8_t *buf, int len)
00168 {
00169     uint8_t section[1024], *q;
00170     unsigned int tot_len;
00171     /* reserved_future_use field must be set to 1 for SDT */
00172     unsigned int flags = tid == SDT_TID ? 0xf000 : 0xb000;
00173 
00174     tot_len = 3 + 5 + len + 4;
00175     /* check if not too big */
00176     if (tot_len > 1024)
00177         return -1;
00178 
00179     q = section;
00180     *q++ = tid;
00181     put16(&q, flags | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
00182     put16(&q, id);
00183     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
00184     *q++ = sec_num;
00185     *q++ = last_sec_num;
00186     memcpy(q, buf, len);
00187 
00188     mpegts_write_section(s, section, tot_len);
00189     return 0;
00190 }
00191 
00192 /*********************************************/
00193 /* mpegts writer */
00194 
00195 #define DEFAULT_PROVIDER_NAME   "Libav"
00196 #define DEFAULT_SERVICE_NAME    "Service01"
00197 
00198 /* we retransmit the SI info at this rate */
00199 #define SDT_RETRANS_TIME 500
00200 #define PAT_RETRANS_TIME 100
00201 #define PCR_RETRANS_TIME 20
00202 
00203 typedef struct MpegTSWriteStream {
00204     struct MpegTSService *service;
00205     int pid; /* stream associated pid */
00206     int cc;
00207     int payload_size;
00208     int first_pts_check; 
00209     int64_t payload_pts;
00210     int64_t payload_dts;
00211     int payload_flags;
00212     uint8_t *payload;
00213     ADTSContext *adts;
00214 } MpegTSWriteStream;
00215 
00216 static void mpegts_write_pat(AVFormatContext *s)
00217 {
00218     MpegTSWrite *ts = s->priv_data;
00219     MpegTSService *service;
00220     uint8_t data[1012], *q;
00221     int i;
00222 
00223     q = data;
00224     for(i = 0; i < ts->nb_services; i++) {
00225         service = ts->services[i];
00226         put16(&q, service->sid);
00227         put16(&q, 0xe000 | service->pmt.pid);
00228     }
00229     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
00230                           data, q - data);
00231 }
00232 
00233 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
00234 {
00235     //    MpegTSWrite *ts = s->priv_data;
00236     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
00237     int val, stream_type, i;
00238 
00239     q = data;
00240     put16(&q, 0xe000 | service->pcr_pid);
00241 
00242     program_info_length_ptr = q;
00243     q += 2; /* patched after */
00244 
00245     /* put program info here */
00246 
00247     val = 0xf000 | (q - program_info_length_ptr - 2);
00248     program_info_length_ptr[0] = val >> 8;
00249     program_info_length_ptr[1] = val;
00250 
00251     for(i = 0; i < s->nb_streams; i++) {
00252         AVStream *st = s->streams[i];
00253         MpegTSWriteStream *ts_st = st->priv_data;
00254         AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,0);
00255         switch(st->codec->codec_id) {
00256         case CODEC_ID_MPEG1VIDEO:
00257         case CODEC_ID_MPEG2VIDEO:
00258             stream_type = STREAM_TYPE_VIDEO_MPEG2;
00259             break;
00260         case CODEC_ID_MPEG4:
00261             stream_type = STREAM_TYPE_VIDEO_MPEG4;
00262             break;
00263         case CODEC_ID_H264:
00264             stream_type = STREAM_TYPE_VIDEO_H264;
00265             break;
00266         case CODEC_ID_DIRAC:
00267             stream_type = STREAM_TYPE_VIDEO_DIRAC;
00268             break;
00269         case CODEC_ID_MP2:
00270         case CODEC_ID_MP3:
00271             stream_type = STREAM_TYPE_AUDIO_MPEG1;
00272             break;
00273         case CODEC_ID_AAC:
00274             stream_type = STREAM_TYPE_AUDIO_AAC;
00275             break;
00276         case CODEC_ID_AAC_LATM:
00277             stream_type = STREAM_TYPE_AUDIO_AAC_LATM;
00278             break;
00279         case CODEC_ID_AC3:
00280             stream_type = STREAM_TYPE_AUDIO_AC3;
00281             break;
00282         default:
00283             stream_type = STREAM_TYPE_PRIVATE_DATA;
00284             break;
00285         }
00286         *q++ = stream_type;
00287         put16(&q, 0xe000 | ts_st->pid);
00288         desc_length_ptr = q;
00289         q += 2; /* patched after */
00290 
00291         /* write optional descriptors here */
00292         switch(st->codec->codec_type) {
00293         case AVMEDIA_TYPE_AUDIO:
00294             if (lang) {
00295                 char *p;
00296                 char *next = lang->value;
00297                 uint8_t *len_ptr;
00298 
00299                 *q++ = 0x0a; /* ISO 639 language descriptor */
00300                 len_ptr = q++;
00301                 *len_ptr = 0;
00302 
00303                 for (p = lang->value; next && *len_ptr < 255 / 4 * 4; p = next + 1) {
00304                     next = strchr(p, ',');
00305                     if (strlen(p) != 3 && (!next || next != p + 3))
00306                         continue; /* not a 3-letter code */
00307 
00308                     *q++ = *p++;
00309                     *q++ = *p++;
00310                     *q++ = *p++;
00311 
00312                 if (st->disposition & AV_DISPOSITION_CLEAN_EFFECTS)
00313                     *q++ = 0x01;
00314                 else if (st->disposition & AV_DISPOSITION_HEARING_IMPAIRED)
00315                     *q++ = 0x02;
00316                 else if (st->disposition & AV_DISPOSITION_VISUAL_IMPAIRED)
00317                     *q++ = 0x03;
00318                 else
00319                     *q++ = 0; /* undefined type */
00320 
00321                     *len_ptr += 4;
00322                 }
00323 
00324                 if (*len_ptr == 0)
00325                     q -= 2; /* no language codes were written */
00326             }
00327             break;
00328         case AVMEDIA_TYPE_SUBTITLE:
00329             {
00330                 const char *language;
00331                 language = lang && strlen(lang->value)==3 ? lang->value : "eng";
00332                 *q++ = 0x59;
00333                 *q++ = 8;
00334                 *q++ = language[0];
00335                 *q++ = language[1];
00336                 *q++ = language[2];
00337                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
00338                 if(st->codec->extradata_size == 4) {
00339                     memcpy(q, st->codec->extradata, 4);
00340                     q += 4;
00341                 } else {
00342                     put16(&q, 1); /* page id */
00343                     put16(&q, 1); /* ancillary page id */
00344                 }
00345             }
00346             break;
00347         case AVMEDIA_TYPE_VIDEO:
00348             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
00349                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
00350                 *q++ = 4;
00351                 *q++ = 'd';
00352                 *q++ = 'r';
00353                 *q++ = 'a';
00354                 *q++ = 'c';
00355             }
00356             break;
00357         }
00358 
00359         val = 0xf000 | (q - desc_length_ptr - 2);
00360         desc_length_ptr[0] = val >> 8;
00361         desc_length_ptr[1] = val;
00362     }
00363     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
00364                           data, q - data);
00365 }
00366 
00367 /* NOTE: str == NULL is accepted for an empty string */
00368 static void putstr8(uint8_t **q_ptr, const char *str)
00369 {
00370     uint8_t *q;
00371     int len;
00372 
00373     q = *q_ptr;
00374     if (!str)
00375         len = 0;
00376     else
00377         len = strlen(str);
00378     *q++ = len;
00379     memcpy(q, str, len);
00380     q += len;
00381     *q_ptr = q;
00382 }
00383 
00384 static void mpegts_write_sdt(AVFormatContext *s)
00385 {
00386     MpegTSWrite *ts = s->priv_data;
00387     MpegTSService *service;
00388     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
00389     int i, running_status, free_ca_mode, val;
00390 
00391     q = data;
00392     put16(&q, ts->onid);
00393     *q++ = 0xff;
00394     for(i = 0; i < ts->nb_services; i++) {
00395         service = ts->services[i];
00396         put16(&q, service->sid);
00397         *q++ = 0xfc | 0x00; /* currently no EIT info */
00398         desc_list_len_ptr = q;
00399         q += 2;
00400         running_status = 4; /* running */
00401         free_ca_mode = 0;
00402 
00403         /* write only one descriptor for the service name and provider */
00404         *q++ = 0x48;
00405         desc_len_ptr = q;
00406         q++;
00407         *q++ = 0x01; /* digital television service */
00408         putstr8(&q, service->provider_name);
00409         putstr8(&q, service->name);
00410         desc_len_ptr[0] = q - desc_len_ptr - 1;
00411 
00412         /* fill descriptor length */
00413         val = (running_status << 13) | (free_ca_mode << 12) |
00414             (q - desc_list_len_ptr - 2);
00415         desc_list_len_ptr[0] = val >> 8;
00416         desc_list_len_ptr[1] = val;
00417     }
00418     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
00419                           data, q - data);
00420 }
00421 
00422 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
00423                                          int sid,
00424                                          const char *provider_name,
00425                                          const char *name)
00426 {
00427     MpegTSService *service;
00428 
00429     service = av_mallocz(sizeof(MpegTSService));
00430     if (!service)
00431         return NULL;
00432     service->pmt.pid = ts->pmt_start_pid + ts->nb_services;
00433     service->sid = sid;
00434     service->provider_name = av_strdup(provider_name);
00435     service->name = av_strdup(name);
00436     service->pcr_pid = 0x1fff;
00437     dynarray_add(&ts->services, &ts->nb_services, service);
00438     return service;
00439 }
00440 
00441 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
00442 {
00443     AVFormatContext *ctx = s->opaque;
00444     avio_write(ctx->pb, packet, TS_PACKET_SIZE);
00445 }
00446 
00447 static int mpegts_write_header(AVFormatContext *s)
00448 {
00449     MpegTSWrite *ts = s->priv_data;
00450     MpegTSWriteStream *ts_st;
00451     MpegTSService *service;
00452     AVStream *st, *pcr_st = NULL;
00453     AVDictionaryEntry *title, *provider;
00454     int i, j;
00455     const char *service_name;
00456     const char *provider_name;
00457     int *pids;
00458 
00459     // round up to a whole number of TS packets
00460     ts->pes_payload_size = (ts->pes_payload_size + 14 + 183) / 184 * 184 - 14;
00461 
00462     ts->tsid = ts->transport_stream_id;
00463     ts->onid = ts->original_network_id;
00464     /* allocate a single DVB service */
00465     title = av_dict_get(s->metadata, "service_name", NULL, 0);
00466     if (!title)
00467         title = av_dict_get(s->metadata, "title", NULL, 0);
00468     service_name = title ? title->value : DEFAULT_SERVICE_NAME;
00469     provider = av_dict_get(s->metadata, "service_provider", NULL, 0);
00470     provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;
00471     service = mpegts_add_service(ts, ts->service_id, provider_name, service_name);
00472     service->pmt.write_packet = section_write_packet;
00473     service->pmt.opaque = s;
00474     service->pmt.cc = 15;
00475 
00476     ts->pat.pid = PAT_PID;
00477     ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write
00478     ts->pat.write_packet = section_write_packet;
00479     ts->pat.opaque = s;
00480 
00481     ts->sdt.pid = SDT_PID;
00482     ts->sdt.cc = 15;
00483     ts->sdt.write_packet = section_write_packet;
00484     ts->sdt.opaque = s;
00485 
00486     pids = av_malloc(s->nb_streams * sizeof(*pids));
00487     if (!pids)
00488         return AVERROR(ENOMEM);
00489 
00490     /* assign pids to each stream */
00491     for(i = 0;i < s->nb_streams; i++) {
00492         st = s->streams[i];
00493         avpriv_set_pts_info(st, 33, 1, 90000);
00494         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
00495         if (!ts_st)
00496             goto fail;
00497         st->priv_data = ts_st;
00498         ts_st->payload = av_mallocz(ts->pes_payload_size);
00499         if (!ts_st->payload)
00500             goto fail;
00501         ts_st->service = service;
00502         /* MPEG pid values < 16 are reserved. Applications which set st->id in
00503          * this range are assigned a calculated pid. */
00504         if (st->id < 16) {
00505             ts_st->pid = ts->start_pid + i;
00506         } else if (st->id < 0x1FFF) {
00507             ts_st->pid = st->id;
00508         } else {
00509             av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);
00510             goto fail;
00511         }
00512         if (ts_st->pid == service->pmt.pid) {
00513             av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
00514             goto fail;
00515         }
00516         for (j = 0; j < i; j++)
00517             if (pids[j] == ts_st->pid) {
00518                 av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
00519                 goto fail;
00520             }
00521         pids[i] = ts_st->pid;
00522         ts_st->payload_pts = AV_NOPTS_VALUE;
00523         ts_st->payload_dts = AV_NOPTS_VALUE;
00524         ts_st->first_pts_check = 1;
00525         ts_st->cc = 15;
00526         /* update PCR pid by using the first video stream */
00527         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
00528             service->pcr_pid == 0x1fff) {
00529             service->pcr_pid = ts_st->pid;
00530             pcr_st = st;
00531         }
00532         if (st->codec->codec_id == CODEC_ID_AAC &&
00533             st->codec->extradata_size > 0) {
00534             ts_st->adts = av_mallocz(sizeof(*ts_st->adts));
00535             if (!ts_st->adts)
00536                 goto fail;
00537             if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,
00538                                          st->codec->extradata_size) < 0)
00539                 goto fail;
00540         }
00541     }
00542 
00543     av_free(pids);
00544 
00545     /* if no video stream, use the first stream as PCR */
00546     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
00547         pcr_st = s->streams[0];
00548         ts_st = pcr_st->priv_data;
00549         service->pcr_pid = ts_st->pid;
00550     }
00551 
00552 #if FF_API_MUXRATE
00553     if (s->mux_rate)
00554         ts->mux_rate = s->mux_rate;
00555 #endif
00556 
00557     if (ts->mux_rate > 1) {
00558         service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
00559             (TS_PACKET_SIZE * 8 * 1000);
00560         ts->sdt_packet_period      = (ts->mux_rate * SDT_RETRANS_TIME) /
00561             (TS_PACKET_SIZE * 8 * 1000);
00562         ts->pat_packet_period      = (ts->mux_rate * PAT_RETRANS_TIME) /
00563             (TS_PACKET_SIZE * 8 * 1000);
00564 
00565         ts->first_pcr = av_rescale(s->max_delay, PCR_TIME_BASE, AV_TIME_BASE);
00566     } else {
00567         /* Arbitrary values, PAT/PMT could be written on key frames */
00568         ts->sdt_packet_period = 200;
00569         ts->pat_packet_period = 40;
00570         if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00571             if (!pcr_st->codec->frame_size) {
00572                 av_log(s, AV_LOG_WARNING, "frame size not set\n");
00573                 service->pcr_packet_period =
00574                     pcr_st->codec->sample_rate/(10*512);
00575             } else {
00576                 service->pcr_packet_period =
00577                     pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
00578             }
00579         } else {
00580             // max delta PCR 0.1s
00581             service->pcr_packet_period =
00582                 pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
00583         }
00584     }
00585 
00586     // output a PCR as soon as possible
00587     service->pcr_packet_count = service->pcr_packet_period;
00588     ts->pat_packet_count = ts->pat_packet_period-1;
00589     ts->sdt_packet_count = ts->sdt_packet_period-1;
00590 
00591     if (ts->mux_rate == 1)
00592         av_log(s, AV_LOG_INFO, "muxrate VBR, ");
00593     else
00594         av_log(s, AV_LOG_INFO, "muxrate %d, ", ts->mux_rate);
00595     av_log(s, AV_LOG_INFO, "pcr every %d pkts, "
00596            "sdt every %d, pat/pmt every %d pkts\n",
00597            service->pcr_packet_period,
00598            ts->sdt_packet_period, ts->pat_packet_period);
00599 
00600     avio_flush(s->pb);
00601 
00602     return 0;
00603 
00604  fail:
00605     av_free(pids);
00606     for(i = 0;i < s->nb_streams; i++) {
00607         MpegTSWriteStream *ts_st;
00608         st = s->streams[i];
00609         ts_st = st->priv_data;
00610         if (ts_st) {
00611             av_freep(&ts_st->payload);
00612             av_freep(&ts_st->adts);
00613         }
00614         av_freep(&st->priv_data);
00615     }
00616     return -1;
00617 }
00618 
00619 /* send SDT, PAT and PMT tables regulary */
00620 static void retransmit_si_info(AVFormatContext *s)
00621 {
00622     MpegTSWrite *ts = s->priv_data;
00623     int i;
00624 
00625     if (++ts->sdt_packet_count == ts->sdt_packet_period) {
00626         ts->sdt_packet_count = 0;
00627         mpegts_write_sdt(s);
00628     }
00629     if (++ts->pat_packet_count == ts->pat_packet_period) {
00630         ts->pat_packet_count = 0;
00631         mpegts_write_pat(s);
00632         for(i = 0; i < ts->nb_services; i++) {
00633             mpegts_write_pmt(s, ts->services[i]);
00634         }
00635     }
00636 }
00637 
00638 static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
00639 {
00640     return av_rescale(avio_tell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +
00641            ts->first_pcr;
00642 }
00643 
00644 static int write_pcr_bits(uint8_t *buf, int64_t pcr)
00645 {
00646     int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;
00647 
00648     *buf++ = pcr_high >> 25;
00649     *buf++ = pcr_high >> 17;
00650     *buf++ = pcr_high >> 9;
00651     *buf++ = pcr_high >> 1;
00652     *buf++ = pcr_high << 7 | pcr_low >> 8 | 0x7e;
00653     *buf++ = pcr_low;
00654 
00655     return 6;
00656 }
00657 
00658 /* Write a single null transport stream packet */
00659 static void mpegts_insert_null_packet(AVFormatContext *s)
00660 {
00661     uint8_t *q;
00662     uint8_t buf[TS_PACKET_SIZE];
00663 
00664     q = buf;
00665     *q++ = 0x47;
00666     *q++ = 0x00 | 0x1f;
00667     *q++ = 0xff;
00668     *q++ = 0x10;
00669     memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));
00670     avio_write(s->pb, buf, TS_PACKET_SIZE);
00671 }
00672 
00673 /* Write a single transport stream packet with a PCR and no payload */
00674 static void mpegts_insert_pcr_only(AVFormatContext *s, AVStream *st)
00675 {
00676     MpegTSWrite *ts = s->priv_data;
00677     MpegTSWriteStream *ts_st = st->priv_data;
00678     uint8_t *q;
00679     uint8_t buf[TS_PACKET_SIZE];
00680 
00681     q = buf;
00682     *q++ = 0x47;
00683     *q++ = ts_st->pid >> 8;
00684     *q++ = ts_st->pid;
00685     *q++ = 0x20 | ts_st->cc;   /* Adaptation only */
00686     /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
00687     *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
00688     *q++ = 0x10;               /* Adaptation flags: PCR present */
00689 
00690     /* PCR coded into 6 bytes */
00691     q += write_pcr_bits(q, get_pcr(ts, s->pb));
00692 
00693     /* stuffing bytes */
00694     memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));
00695     avio_write(s->pb, buf, TS_PACKET_SIZE);
00696 }
00697 
00698 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
00699 {
00700     int val;
00701 
00702     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
00703     *q++ = val;
00704     val = (((pts >> 15) & 0x7fff) << 1) | 1;
00705     *q++ = val >> 8;
00706     *q++ = val;
00707     val = (((pts) & 0x7fff) << 1) | 1;
00708     *q++ = val >> 8;
00709     *q++ = val;
00710 }
00711 
00712 /* Set an adaptation field flag in an MPEG-TS packet*/
00713 static void set_af_flag(uint8_t *pkt, int flag)
00714 {
00715     // expect at least one flag to set
00716     assert(flag);
00717 
00718     if ((pkt[3] & 0x20) == 0) {
00719         // no AF yet, set adaptation field flag
00720         pkt[3] |= 0x20;
00721         // 1 byte length, no flags
00722         pkt[4] = 1;
00723         pkt[5] = 0;
00724     }
00725     pkt[5] |= flag;
00726 }
00727 
00728 /* Extend the adaptation field by size bytes */
00729 static void extend_af(uint8_t *pkt, int size)
00730 {
00731     // expect already existing adaptation field
00732     assert(pkt[3] & 0x20);
00733     pkt[4] += size;
00734 }
00735 
00736 /* Get a pointer to MPEG-TS payload (right after TS packet header) */
00737 static uint8_t *get_ts_payload_start(uint8_t *pkt)
00738 {
00739     if (pkt[3] & 0x20)
00740         return pkt + 5 + pkt[4];
00741     else
00742         return pkt + 4;
00743 }
00744 
00745 /* Add a pes header to the front of payload, and segment into an integer number of
00746  * ts packets. The final ts packet is padded using an over-sized adaptation header
00747  * to exactly fill the last ts packet.
00748  * NOTE: 'payload' contains a complete PES payload.
00749  */
00750 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
00751                              const uint8_t *payload, int payload_size,
00752                              int64_t pts, int64_t dts, int key)
00753 {
00754     MpegTSWriteStream *ts_st = st->priv_data;
00755     MpegTSWrite *ts = s->priv_data;
00756     uint8_t buf[TS_PACKET_SIZE];
00757     uint8_t *q;
00758     int val, is_start, len, header_len, write_pcr, private_code, flags;
00759     int afc_len, stuffing_len;
00760     int64_t pcr = -1; /* avoid warning */
00761     int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
00762 
00763     is_start = 1;
00764     while (payload_size > 0) {
00765         retransmit_si_info(s);
00766 
00767         write_pcr = 0;
00768         if (ts_st->pid == ts_st->service->pcr_pid) {
00769             if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
00770                 ts_st->service->pcr_packet_count++;
00771             if (ts_st->service->pcr_packet_count >=
00772                 ts_st->service->pcr_packet_period) {
00773                 ts_st->service->pcr_packet_count = 0;
00774                 write_pcr = 1;
00775             }
00776         }
00777 
00778         if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&
00779             (dts - get_pcr(ts, s->pb)/300) > delay) {
00780             /* pcr insert gets priority over null packet insert */
00781             if (write_pcr)
00782                 mpegts_insert_pcr_only(s, st);
00783             else
00784                 mpegts_insert_null_packet(s);
00785             continue; /* recalculate write_pcr and possibly retransmit si_info */
00786         }
00787 
00788         /* prepare packet header */
00789         q = buf;
00790         *q++ = 0x47;
00791         val = (ts_st->pid >> 8);
00792         if (is_start)
00793             val |= 0x40;
00794         *q++ = val;
00795         *q++ = ts_st->pid;
00796         ts_st->cc = (ts_st->cc + 1) & 0xf;
00797         *q++ = 0x10 | ts_st->cc; // payload indicator + CC
00798         if (key && is_start && pts != AV_NOPTS_VALUE) {
00799             // set Random Access for key frames
00800             if (ts_st->pid == ts_st->service->pcr_pid)
00801                 write_pcr = 1;
00802             set_af_flag(buf, 0x40);
00803             q = get_ts_payload_start(buf);
00804         }
00805         if (write_pcr) {
00806             set_af_flag(buf, 0x10);
00807             q = get_ts_payload_start(buf);
00808             // add 11, pcr references the last byte of program clock reference base
00809             if (ts->mux_rate > 1)
00810                 pcr = get_pcr(ts, s->pb);
00811             else
00812                 pcr = (dts - delay)*300;
00813             if (dts != AV_NOPTS_VALUE && dts < pcr / 300)
00814                 av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
00815             extend_af(buf, write_pcr_bits(q, pcr));
00816             q = get_ts_payload_start(buf);
00817         }
00818         if (is_start) {
00819             int pes_extension = 0;
00820             /* write PES header */
00821             *q++ = 0x00;
00822             *q++ = 0x00;
00823             *q++ = 0x01;
00824             private_code = 0;
00825             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00826                 if (st->codec->codec_id == CODEC_ID_DIRAC) {
00827                     *q++ = 0xfd;
00828                 } else
00829                     *q++ = 0xe0;
00830             } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
00831                        (st->codec->codec_id == CODEC_ID_MP2 ||
00832                         st->codec->codec_id == CODEC_ID_MP3 ||
00833                         st->codec->codec_id == CODEC_ID_AAC)) {
00834                 *q++ = 0xc0;
00835             } else {
00836                 *q++ = 0xbd;
00837                 if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
00838                     private_code = 0x20;
00839                 }
00840             }
00841             header_len = 0;
00842             flags = 0;
00843             if (pts != AV_NOPTS_VALUE) {
00844                 header_len += 5;
00845                 flags |= 0x80;
00846             }
00847             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
00848                 header_len += 5;
00849                 flags |= 0x40;
00850             }
00851             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
00852                 st->codec->codec_id == CODEC_ID_DIRAC) {
00853                 /* set PES_extension_flag */
00854                 pes_extension = 1;
00855                 flags |= 0x01;
00856 
00857                 /*
00858                 * One byte for PES2 extension flag +
00859                 * one byte for extension length +
00860                 * one byte for extension id
00861                 */
00862                 header_len += 3;
00863             }
00864             len = payload_size + header_len + 3;
00865             if (private_code != 0)
00866                 len++;
00867             if (len > 0xffff)
00868                 len = 0;
00869             *q++ = len >> 8;
00870             *q++ = len;
00871             val = 0x80;
00872             /* data alignment indicator is required for subtitle data */
00873             if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE)
00874                 val |= 0x04;
00875             *q++ = val;
00876             *q++ = flags;
00877             *q++ = header_len;
00878             if (pts != AV_NOPTS_VALUE) {
00879                 write_pts(q, flags >> 6, pts);
00880                 q += 5;
00881             }
00882             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
00883                 write_pts(q, 1, dts);
00884                 q += 5;
00885             }
00886             if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
00887                 flags = 0x01;  /* set PES_extension_flag_2 */
00888                 *q++ = flags;
00889                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
00890                 /*
00891                 * Set the stream id extension flag bit to 0 and
00892                 * write the extended stream id
00893                 */
00894                 *q++ = 0x00 | 0x60;
00895             }
00896             if (private_code != 0)
00897                 *q++ = private_code;
00898             is_start = 0;
00899         }
00900         /* header size */
00901         header_len = q - buf;
00902         /* data len */
00903         len = TS_PACKET_SIZE - header_len;
00904         if (len > payload_size)
00905             len = payload_size;
00906         stuffing_len = TS_PACKET_SIZE - header_len - len;
00907         if (stuffing_len > 0) {
00908             /* add stuffing with AFC */
00909             if (buf[3] & 0x20) {
00910                 /* stuffing already present: increase its size */
00911                 afc_len = buf[4] + 1;
00912                 memmove(buf + 4 + afc_len + stuffing_len,
00913                         buf + 4 + afc_len,
00914                         header_len - (4 + afc_len));
00915                 buf[4] += stuffing_len;
00916                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
00917             } else {
00918                 /* add stuffing */
00919                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
00920                 buf[3] |= 0x20;
00921                 buf[4] = stuffing_len - 1;
00922                 if (stuffing_len >= 2) {
00923                     buf[5] = 0x00;
00924                     memset(buf + 6, 0xff, stuffing_len - 2);
00925                 }
00926             }
00927         }
00928         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
00929         payload += len;
00930         payload_size -= len;
00931         avio_write(s->pb, buf, TS_PACKET_SIZE);
00932     }
00933     avio_flush(s->pb);
00934 }
00935 
00936 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
00937 {
00938     AVStream *st = s->streams[pkt->stream_index];
00939     int size = pkt->size;
00940     uint8_t *buf= pkt->data;
00941     uint8_t *data= NULL;
00942     MpegTSWrite *ts = s->priv_data;
00943     MpegTSWriteStream *ts_st = st->priv_data;
00944     const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;
00945     int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
00946 
00947     if (pkt->pts != AV_NOPTS_VALUE)
00948         pts = pkt->pts + delay;
00949     if (pkt->dts != AV_NOPTS_VALUE)
00950         dts = pkt->dts + delay;
00951 
00952     if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {
00953         av_log(s, AV_LOG_ERROR, "first pts value must set\n");
00954         return -1;
00955     }
00956     ts_st->first_pts_check = 0;
00957 
00958     if (st->codec->codec_id == CODEC_ID_H264) {
00959         const uint8_t *p = buf, *buf_end = p+size;
00960         uint32_t state = -1;
00961 
00962         if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
00963             av_log(s, AV_LOG_ERROR, "H.264 bitstream malformed, "
00964                    "no startcode found, use -vbsf h264_mp4toannexb\n");
00965             return -1;
00966         }
00967 
00968         do {
00969             p = avpriv_mpv_find_start_code(p, buf_end, &state);
00970             //av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);
00971         } while (p < buf_end && (state & 0x1f) != 9 &&
00972                  (state & 0x1f) != 5 && (state & 0x1f) != 1);
00973 
00974         if ((state & 0x1f) != 9) { // AUD NAL
00975             data = av_malloc(pkt->size+6);
00976             if (!data)
00977                 return -1;
00978             memcpy(data+6, pkt->data, pkt->size);
00979             AV_WB32(data, 0x00000001);
00980             data[4] = 0x09;
00981             data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bit
00982             buf  = data;
00983             size = pkt->size+6;
00984         }
00985     } else if (st->codec->codec_id == CODEC_ID_AAC) {
00986         if (pkt->size < 2)
00987             return -1;
00988         if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {
00989             ADTSContext *adts = ts_st->adts;
00990             int new_size, err;
00991             if (!adts) {
00992                 av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format "
00993                        "and extradata missing\n");
00994                 return -1;
00995             }
00996             new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;
00997             if ((unsigned)new_size >= INT_MAX)
00998                 return -1;
00999             data = av_malloc(new_size);
01000             if (!data)
01001                 return AVERROR(ENOMEM);
01002             err = ff_adts_write_frame_header(adts, data, pkt->size,
01003                                              adts->pce_size);
01004             if (err < 0) {
01005                 av_free(data);
01006                 return err;
01007             }
01008             if (adts->pce_size) {
01009                 memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);
01010                 adts->pce_size = 0;
01011             }
01012             memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);
01013             buf = data;
01014             size = new_size;
01015         }
01016     }
01017 
01018     if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {
01019         // for video and subtitle, write a single pes packet
01020         mpegts_write_pes(s, st, buf, size, pts, dts, pkt->flags & AV_PKT_FLAG_KEY);
01021         av_free(data);
01022         return 0;
01023     }
01024 
01025     if (ts_st->payload_size + size > ts->pes_payload_size) {
01026         if (ts_st->payload_size) {
01027             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
01028                              ts_st->payload_pts, ts_st->payload_dts,
01029                              ts_st->payload_flags & AV_PKT_FLAG_KEY);
01030             ts_st->payload_size = 0;
01031         }
01032         if (size > ts->pes_payload_size) {
01033             mpegts_write_pes(s, st, buf, size, pts, dts,
01034                              pkt->flags & AV_PKT_FLAG_KEY);
01035             av_free(data);
01036             return 0;
01037         }
01038     }
01039 
01040     if (!ts_st->payload_size) {
01041         ts_st->payload_pts = pts;
01042         ts_st->payload_dts = dts;
01043         ts_st->payload_flags = pkt->flags;
01044     }
01045 
01046     memcpy(ts_st->payload + ts_st->payload_size, buf, size);
01047     ts_st->payload_size += size;
01048 
01049     av_free(data);
01050 
01051     return 0;
01052 }
01053 
01054 static int mpegts_write_end(AVFormatContext *s)
01055 {
01056     MpegTSWrite *ts = s->priv_data;
01057     MpegTSWriteStream *ts_st;
01058     MpegTSService *service;
01059     AVStream *st;
01060     int i;
01061 
01062     /* flush current packets */
01063     for(i = 0; i < s->nb_streams; i++) {
01064         st = s->streams[i];
01065         ts_st = st->priv_data;
01066         if (ts_st->payload_size > 0) {
01067             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
01068                              ts_st->payload_pts, ts_st->payload_dts,
01069                              ts_st->payload_flags & AV_PKT_FLAG_KEY);
01070         }
01071         av_freep(&ts_st->payload);
01072         av_freep(&ts_st->adts);
01073     }
01074     avio_flush(s->pb);
01075 
01076     for(i = 0; i < ts->nb_services; i++) {
01077         service = ts->services[i];
01078         av_freep(&service->provider_name);
01079         av_freep(&service->name);
01080         av_free(service);
01081     }
01082     av_free(ts->services);
01083 
01084     return 0;
01085 }
01086 
01087 AVOutputFormat ff_mpegts_muxer = {
01088     .name              = "mpegts",
01089     .long_name         = NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
01090     .mime_type         = "video/x-mpegts",
01091     .extensions        = "ts,m2t",
01092     .priv_data_size    = sizeof(MpegTSWrite),
01093     .audio_codec       = CODEC_ID_MP2,
01094     .video_codec       = CODEC_ID_MPEG2VIDEO,
01095     .write_header      = mpegts_write_header,
01096     .write_packet      = mpegts_write_packet,
01097     .write_trailer     = mpegts_write_end,
01098     .priv_class = &mpegts_muxer_class,
01099 };
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