FFmpeg: libavformat/mpegtsenc.c Source File

00001 /*
00002  * MPEG2 transport stream (aka DVB) muxer
00003  * Copyright (c) 2003 Fabrice Bellard
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 "libavcodec/mpegvideo.h"
00025 #include "avformat.h"
00026 #include "mpegts.h"
00027 
00028 /* write DVB SI sections */
00029 
00030 /*********************************************/
00031 /* mpegts section writer */
00032 
00033 typedef struct MpegTSSection {
00034     int pid;
00035     int cc;
00036     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
00037     void *opaque;
00038 } MpegTSSection;
00039 
00040 typedef struct MpegTSService {
00041     MpegTSSection pmt; /* MPEG2 pmt table context */
00042     int sid;           /* service ID */
00043     char *name;
00044     char *provider_name;
00045     int pcr_pid;
00046     int pcr_packet_count;
00047     int pcr_packet_freq;
00048 } MpegTSService;
00049 
00050 typedef struct MpegTSWrite {
00051     MpegTSSection pat; /* MPEG2 pat table */
00052     MpegTSSection sdt; /* MPEG2 sdt table context */
00053     MpegTSService **services;
00054     int sdt_packet_count;
00055     int sdt_packet_freq;
00056     int pat_packet_count;
00057     int pat_packet_freq;
00058     int nb_services;
00059     int onid;
00060     int tsid;
00061     uint64_t cur_pcr;
00062     int mux_rate;
00063 } MpegTSWrite;
00064 
00065 /* NOTE: 4 bytes must be left at the end for the crc32 */
00066 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
00067 {
00068     MpegTSWrite *ts = ((AVFormatContext*)s->opaque)->priv_data;
00069     unsigned int crc;
00070     unsigned char packet[TS_PACKET_SIZE];
00071     const unsigned char *buf_ptr;
00072     unsigned char *q;
00073     int first, b, len1, left;
00074 
00075     crc = bswap_32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
00076     buf[len - 4] = (crc >> 24) & 0xff;
00077     buf[len - 3] = (crc >> 16) & 0xff;
00078     buf[len - 2] = (crc >> 8) & 0xff;
00079     buf[len - 1] = (crc) & 0xff;
00080 
00081     /* send each packet */
00082     buf_ptr = buf;
00083     while (len > 0) {
00084         first = (buf == buf_ptr);
00085         q = packet;
00086         *q++ = 0x47;
00087         b = (s->pid >> 8);
00088         if (first)
00089             b |= 0x40;
00090         *q++ = b;
00091         *q++ = s->pid;
00092         *q++ = 0x10 | s->cc;
00093         s->cc = (s->cc + 1) & 0xf;
00094         if (first)
00095             *q++ = 0; /* 0 offset */
00096         len1 = TS_PACKET_SIZE - (q - packet);
00097         if (len1 > len)
00098             len1 = len;
00099         memcpy(q, buf_ptr, len1);
00100         q += len1;
00101         /* add known padding data */
00102         left = TS_PACKET_SIZE - (q - packet);
00103         if (left > 0)
00104             memset(q, 0xff, left);
00105 
00106         s->write_packet(s, packet);
00107 
00108         buf_ptr += len1;
00109         len -= len1;
00110 
00111         ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
00112     }
00113 }
00114 
00115 static inline void put16(uint8_t **q_ptr, int val)
00116 {
00117     uint8_t *q;
00118     q = *q_ptr;
00119     *q++ = val >> 8;
00120     *q++ = val;
00121     *q_ptr = q;
00122 }
00123 
00124 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
00125                           int version, int sec_num, int last_sec_num,
00126                           uint8_t *buf, int len)
00127 {
00128     uint8_t section[1024], *q;
00129     unsigned int tot_len;
00130 
00131     tot_len = 3 + 5 + len + 4;
00132     /* check if not too big */
00133     if (tot_len > 1024)
00134         return -1;
00135 
00136     q = section;
00137     *q++ = tid;
00138     put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
00139     put16(&q, id);
00140     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
00141     *q++ = sec_num;
00142     *q++ = last_sec_num;
00143     memcpy(q, buf, len);
00144 
00145     mpegts_write_section(s, section, tot_len);
00146     return 0;
00147 }
00148 
00149 /*********************************************/
00150 /* mpegts writer */
00151 
00152 #define DEFAULT_PMT_START_PID   0x1000
00153 #define DEFAULT_START_PID       0x0100
00154 #define DEFAULT_PROVIDER_NAME   "FFmpeg"
00155 #define DEFAULT_SERVICE_NAME    "Service01"
00156 
00157 /* default network id, transport stream and service identifiers */
00158 #define DEFAULT_ONID            0x0001
00159 #define DEFAULT_TSID            0x0001
00160 #define DEFAULT_SID             0x0001
00161 
00162 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
00163 #define DEFAULT_PES_HEADER_FREQ 16
00164 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
00165 
00166 /* we retransmit the SI info at this rate */
00167 #define SDT_RETRANS_TIME 500
00168 #define PAT_RETRANS_TIME 100
00169 #define PCR_RETRANS_TIME 20
00170 
00171 typedef struct MpegTSWriteStream {
00172     struct MpegTSService *service;
00173     int pid; /* stream associated pid */
00174     int cc;
00175     int payload_index;
00176     int64_t payload_pts;
00177     int64_t payload_dts;
00178     uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
00179 } MpegTSWriteStream;
00180 
00181 static void mpegts_write_pat(AVFormatContext *s)
00182 {
00183     MpegTSWrite *ts = s->priv_data;
00184     MpegTSService *service;
00185     uint8_t data[1012], *q;
00186     int i;
00187 
00188     q = data;
00189     for(i = 0; i < ts->nb_services; i++) {
00190         service = ts->services[i];
00191         put16(&q, service->sid);
00192         put16(&q, 0xe000 | service->pmt.pid);
00193     }
00194     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
00195                           data, q - data);
00196 }
00197 
00198 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
00199 {
00200     //    MpegTSWrite *ts = s->priv_data;
00201     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
00202     int val, stream_type, i;
00203 
00204     q = data;
00205     put16(&q, 0xe000 | service->pcr_pid);
00206 
00207     program_info_length_ptr = q;
00208     q += 2; /* patched after */
00209 
00210     /* put program info here */
00211 
00212     val = 0xf000 | (q - program_info_length_ptr - 2);
00213     program_info_length_ptr[0] = val >> 8;
00214     program_info_length_ptr[1] = val;
00215 
00216     for(i = 0; i < s->nb_streams; i++) {
00217         AVStream *st = s->streams[i];
00218         MpegTSWriteStream *ts_st = st->priv_data;
00219         AVMetadataTag *lang = av_metadata_get(st->metadata, "language", NULL,0);
00220         switch(st->codec->codec_id) {
00221         case CODEC_ID_MPEG1VIDEO:
00222         case CODEC_ID_MPEG2VIDEO:
00223             stream_type = STREAM_TYPE_VIDEO_MPEG2;
00224             break;
00225         case CODEC_ID_MPEG4:
00226             stream_type = STREAM_TYPE_VIDEO_MPEG4;
00227             break;
00228         case CODEC_ID_H264:
00229             stream_type = STREAM_TYPE_VIDEO_H264;
00230             break;
00231         case CODEC_ID_DIRAC:
00232             stream_type = STREAM_TYPE_VIDEO_DIRAC;
00233             break;
00234         case CODEC_ID_MP2:
00235         case CODEC_ID_MP3:
00236             stream_type = STREAM_TYPE_AUDIO_MPEG1;
00237             break;
00238         case CODEC_ID_AAC:
00239             stream_type = STREAM_TYPE_AUDIO_AAC;
00240             break;
00241         case CODEC_ID_AC3:
00242             stream_type = STREAM_TYPE_AUDIO_AC3;
00243             break;
00244         default:
00245             stream_type = STREAM_TYPE_PRIVATE_DATA;
00246             break;
00247         }
00248         *q++ = stream_type;
00249         put16(&q, 0xe000 | ts_st->pid);
00250         desc_length_ptr = q;
00251         q += 2; /* patched after */
00252 
00253         /* write optional descriptors here */
00254         switch(st->codec->codec_type) {
00255         case CODEC_TYPE_AUDIO:
00256             if (lang && strlen(lang->value) == 3) {
00257                 *q++ = 0x0a; /* ISO 639 language descriptor */
00258                 *q++ = 4;
00259                 *q++ = lang->value[0];
00260                 *q++ = lang->value[1];
00261                 *q++ = lang->value[2];
00262                 *q++ = 0; /* undefined type */
00263             }
00264             break;
00265         case CODEC_TYPE_SUBTITLE:
00266             {
00267                 const char *language;
00268                 language = lang && strlen(lang->value)==3 ? lang->value : "eng";
00269                 *q++ = 0x59;
00270                 *q++ = 8;
00271                 *q++ = language[0];
00272                 *q++ = language[1];
00273                 *q++ = language[2];
00274                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
00275                 put16(&q, 1); /* page id */
00276                 put16(&q, 1); /* ancillary page id */
00277             }
00278             break;
00279         case CODEC_TYPE_VIDEO:
00280             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
00281                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
00282                 *q++ = 4;
00283                 *q++ = 'd';
00284                 *q++ = 'r';
00285                 *q++ = 'a';
00286                 *q++ = 'c';
00287             }
00288             break;
00289         }
00290 
00291         val = 0xf000 | (q - desc_length_ptr - 2);
00292         desc_length_ptr[0] = val >> 8;
00293         desc_length_ptr[1] = val;
00294     }
00295     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
00296                           data, q - data);
00297 }
00298 
00299 /* NOTE: str == NULL is accepted for an empty string */
00300 static void putstr8(uint8_t **q_ptr, const char *str)
00301 {
00302     uint8_t *q;
00303     int len;
00304 
00305     q = *q_ptr;
00306     if (!str)
00307         len = 0;
00308     else
00309         len = strlen(str);
00310     *q++ = len;
00311     memcpy(q, str, len);
00312     q += len;
00313     *q_ptr = q;
00314 }
00315 
00316 static void mpegts_write_sdt(AVFormatContext *s)
00317 {
00318     MpegTSWrite *ts = s->priv_data;
00319     MpegTSService *service;
00320     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
00321     int i, running_status, free_ca_mode, val;
00322 
00323     q = data;
00324     put16(&q, ts->onid);
00325     *q++ = 0xff;
00326     for(i = 0; i < ts->nb_services; i++) {
00327         service = ts->services[i];
00328         put16(&q, service->sid);
00329         *q++ = 0xfc | 0x00; /* currently no EIT info */
00330         desc_list_len_ptr = q;
00331         q += 2;
00332         running_status = 4; /* running */
00333         free_ca_mode = 0;
00334 
00335         /* write only one descriptor for the service name and provider */
00336         *q++ = 0x48;
00337         desc_len_ptr = q;
00338         q++;
00339         *q++ = 0x01; /* digital television service */
00340         putstr8(&q, service->provider_name);
00341         putstr8(&q, service->name);
00342         desc_len_ptr[0] = q - desc_len_ptr - 1;
00343 
00344         /* fill descriptor length */
00345         val = (running_status << 13) | (free_ca_mode << 12) |
00346             (q - desc_list_len_ptr - 2);
00347         desc_list_len_ptr[0] = val >> 8;
00348         desc_list_len_ptr[1] = val;
00349     }
00350     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
00351                           data, q - data);
00352 }
00353 
00354 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
00355                                          int sid,
00356                                          const char *provider_name,
00357                                          const char *name)
00358 {
00359     MpegTSService *service;
00360 
00361     service = av_mallocz(sizeof(MpegTSService));
00362     if (!service)
00363         return NULL;
00364     service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
00365     service->sid = sid;
00366     service->provider_name = av_strdup(provider_name);
00367     service->name = av_strdup(name);
00368     service->pcr_pid = 0x1fff;
00369     dynarray_add(&ts->services, &ts->nb_services, service);
00370     return service;
00371 }
00372 
00373 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
00374 {
00375     AVFormatContext *ctx = s->opaque;
00376     put_buffer(ctx->pb, packet, TS_PACKET_SIZE);
00377 }
00378 
00379 static int mpegts_write_header(AVFormatContext *s)
00380 {
00381     MpegTSWrite *ts = s->priv_data;
00382     MpegTSWriteStream *ts_st;
00383     MpegTSService *service;
00384     AVStream *st;
00385     AVMetadataTag *title;
00386     int i, total_bit_rate;
00387     const char *service_name;
00388     uint64_t sdt_size, pat_pmt_size, pos;
00389 
00390     ts->tsid = DEFAULT_TSID;
00391     ts->onid = DEFAULT_ONID;
00392     /* allocate a single DVB service */
00393     title = av_metadata_get(s->metadata, "title", NULL, 0);
00394     service_name = title ? title->value : DEFAULT_SERVICE_NAME;
00395     service = mpegts_add_service(ts, DEFAULT_SID,
00396                                  DEFAULT_PROVIDER_NAME, service_name);
00397     service->pmt.write_packet = section_write_packet;
00398     service->pmt.opaque = s;
00399 
00400     ts->pat.pid = PAT_PID;
00401     ts->pat.cc = 0;
00402     ts->pat.write_packet = section_write_packet;
00403     ts->pat.opaque = s;
00404 
00405     ts->sdt.pid = SDT_PID;
00406     ts->sdt.cc = 0;
00407     ts->sdt.write_packet = section_write_packet;
00408     ts->sdt.opaque = s;
00409 
00410     /* assign pids to each stream */
00411     total_bit_rate = 0;
00412     for(i = 0;i < s->nb_streams; i++) {
00413         st = s->streams[i];
00414         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
00415         if (!ts_st)
00416             goto fail;
00417         st->priv_data = ts_st;
00418         ts_st->service = service;
00419         ts_st->pid = DEFAULT_START_PID + i;
00420         ts_st->payload_pts = AV_NOPTS_VALUE;
00421         ts_st->payload_dts = AV_NOPTS_VALUE;
00422         /* update PCR pid by using the first video stream */
00423         if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
00424             service->pcr_pid == 0x1fff)
00425             service->pcr_pid = ts_st->pid;
00426         total_bit_rate += st->codec->bit_rate;
00427     }
00428 
00429     /* if no video stream, use the first stream as PCR */
00430     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
00431         ts_st = s->streams[0]->priv_data;
00432         service->pcr_pid = ts_st->pid;
00433     }
00434 
00435     if (total_bit_rate <= 8 * 1024)
00436         total_bit_rate = 8 * 1024;
00437     service->pcr_packet_freq = (total_bit_rate * PCR_RETRANS_TIME) /
00438         (TS_PACKET_SIZE * 8 * 1000);
00439     ts->sdt_packet_freq = (total_bit_rate * SDT_RETRANS_TIME) /
00440         (TS_PACKET_SIZE * 8 * 1000);
00441     ts->pat_packet_freq = (total_bit_rate * PAT_RETRANS_TIME) /
00442         (TS_PACKET_SIZE * 8 * 1000);
00443 
00444     ts->mux_rate = 1; // avoid div by 0
00445 
00446     /* write info at the start of the file, so that it will be fast to
00447        find them */
00448     pos = url_ftell(s->pb);
00449     mpegts_write_sdt(s);
00450     sdt_size = url_ftell(s->pb) - pos;
00451     pos = url_ftell(s->pb);
00452     mpegts_write_pat(s);
00453     for(i = 0; i < ts->nb_services; i++) {
00454         mpegts_write_pmt(s, ts->services[i]);
00455     }
00456     pat_pmt_size = url_ftell(s->pb) - pos;
00457 
00458     total_bit_rate +=
00459         total_bit_rate * 25 / (8 * DEFAULT_PES_PAYLOAD_SIZE) + /* PES header size */
00460         total_bit_rate * 4 / (8 * TS_PACKET_SIZE) +            /* TS  header size */
00461         SDT_RETRANS_TIME * sdt_size +                          /* SDT size */
00462         PAT_RETRANS_TIME * pat_pmt_size +                      /* PAT+PMT size */
00463         PCR_RETRANS_TIME * 8;                                  /* PCR size */
00464 
00465     av_log(s, AV_LOG_DEBUG, "muxrate %d freq sdt %d pat %d\n",
00466            total_bit_rate, ts->sdt_packet_freq, ts->pat_packet_freq);
00467 
00468     if (s->mux_rate)
00469         ts->mux_rate = s->mux_rate;
00470     else
00471         ts->mux_rate = total_bit_rate;
00472 
00473     // adjust pcr
00474     ts->cur_pcr /= ts->mux_rate;
00475 
00476     put_flush_packet(s->pb);
00477 
00478     return 0;
00479 
00480  fail:
00481     for(i = 0;i < s->nb_streams; i++) {
00482         st = s->streams[i];
00483         av_free(st->priv_data);
00484     }
00485     return -1;
00486 }
00487 
00488 /* send SDT, PAT and PMT tables regulary */
00489 static void retransmit_si_info(AVFormatContext *s)
00490 {
00491     MpegTSWrite *ts = s->priv_data;
00492     int i;
00493 
00494     if (++ts->sdt_packet_count == ts->sdt_packet_freq) {
00495         ts->sdt_packet_count = 0;
00496         mpegts_write_sdt(s);
00497     }
00498     if (++ts->pat_packet_count == ts->pat_packet_freq) {
00499         ts->pat_packet_count = 0;
00500         mpegts_write_pat(s);
00501         for(i = 0; i < ts->nb_services; i++) {
00502             mpegts_write_pmt(s, ts->services[i]);
00503         }
00504     }
00505 }
00506 
00507 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
00508 {
00509     int val;
00510 
00511     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
00512     *q++ = val;
00513     val = (((pts >> 15) & 0x7fff) << 1) | 1;
00514     *q++ = val >> 8;
00515     *q++ = val;
00516     val = (((pts) & 0x7fff) << 1) | 1;
00517     *q++ = val >> 8;
00518     *q++ = val;
00519 }
00520 
00521 /* NOTE: pes_data contains all the PES packet */
00522 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
00523                              const uint8_t *payload, int payload_size,
00524                              int64_t pts, int64_t dts)
00525 {
00526     MpegTSWriteStream *ts_st = st->priv_data;
00527     MpegTSWrite *ts = s->priv_data;
00528     uint8_t buf[TS_PACKET_SIZE];
00529     uint8_t *q;
00530     int val, is_start, len, header_len, write_pcr, private_code, flags;
00531     int afc_len, stuffing_len;
00532     int64_t pcr = -1; /* avoid warning */
00533 
00534     is_start = 1;
00535     while (payload_size > 0) {
00536         retransmit_si_info(s);
00537 
00538         write_pcr = 0;
00539         if (ts_st->pid == ts_st->service->pcr_pid) {
00540             ts_st->service->pcr_packet_count++;
00541             if (ts_st->service->pcr_packet_count >=
00542                 ts_st->service->pcr_packet_freq) {
00543                 ts_st->service->pcr_packet_count = 0;
00544                 write_pcr = 1;
00545             }
00546         }
00547 
00548         /* prepare packet header */
00549         q = buf;
00550         *q++ = 0x47;
00551         val = (ts_st->pid >> 8);
00552         if (is_start)
00553             val |= 0x40;
00554         *q++ = val;
00555         *q++ = ts_st->pid;
00556         *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
00557         ts_st->cc = (ts_st->cc + 1) & 0xf;
00558         if (write_pcr) {
00559             // add 11, pcr references the last byte of program clock reference base
00560             pcr = ts->cur_pcr + (4+7)*8*90000LL / ts->mux_rate;
00561             if (dts != AV_NOPTS_VALUE && dts < pcr)
00562                 av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
00563             *q++ = 7; /* AFC length */
00564             *q++ = 0x10; /* flags: PCR present */
00565             *q++ = pcr >> 25;
00566             *q++ = pcr >> 17;
00567             *q++ = pcr >> 9;
00568             *q++ = pcr >> 1;
00569             *q++ = (pcr & 1) << 7;
00570             *q++ = 0;
00571         }
00572         if (is_start) {
00573             int pes_extension = 0;
00574             /* write PES header */
00575             *q++ = 0x00;
00576             *q++ = 0x00;
00577             *q++ = 0x01;
00578             private_code = 0;
00579             if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
00580                 if (st->codec->codec_id == CODEC_ID_DIRAC) {
00581                     *q++ = 0xfd;
00582                 } else
00583                     *q++ = 0xe0;
00584             } else if (st->codec->codec_type == CODEC_TYPE_AUDIO &&
00585                        (st->codec->codec_id == CODEC_ID_MP2 ||
00586                         st->codec->codec_id == CODEC_ID_MP3)) {
00587                 *q++ = 0xc0;
00588             } else {
00589                 *q++ = 0xbd;
00590                 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
00591                     private_code = 0x20;
00592                 }
00593             }
00594             header_len = 0;
00595             flags = 0;
00596             if (pts != AV_NOPTS_VALUE) {
00597                 header_len += 5;
00598                 flags |= 0x80;
00599             }
00600             if (dts != AV_NOPTS_VALUE && dts != pts) {
00601                 header_len += 5;
00602                 flags |= 0x40;
00603             }
00604             if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
00605                 st->codec->codec_id == CODEC_ID_DIRAC) {
00606                 /* set PES_extension_flag */
00607                 pes_extension = 1;
00608                 flags |= 0x01;
00609 
00610                 /*
00611                 * One byte for PES2 extension flag +
00612                 * one byte for extension length +
00613                 * one byte for extension id
00614                 */
00615                 header_len += 3;
00616             }
00617             len = payload_size + header_len + 3;
00618             if (private_code != 0)
00619                 len++;
00620             *q++ = len >> 8;
00621             *q++ = len;
00622             val = 0x80;
00623             /* data alignment indicator is required for subtitle data */
00624             if (st->codec->codec_type == CODEC_TYPE_SUBTITLE)
00625                 val |= 0x04;
00626             *q++ = val;
00627             *q++ = flags;
00628             *q++ = header_len;
00629             if (pts != AV_NOPTS_VALUE) {
00630                 write_pts(q, flags >> 6, pts);
00631                 q += 5;
00632             }
00633             if (dts != AV_NOPTS_VALUE && dts != pts) {
00634                 write_pts(q, 1, dts);
00635                 q += 5;
00636             }
00637             if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
00638                 flags = 0x01;  /* set PES_extension_flag_2 */
00639                 *q++ = flags;
00640                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
00641                 /*
00642                 * Set the stream id extension flag bit to 0 and
00643                 * write the extended stream id
00644                 */
00645                 *q++ = 0x00 | 0x60;
00646             }
00647             if (private_code != 0)
00648                 *q++ = private_code;
00649             is_start = 0;
00650         }
00651         /* header size */
00652         header_len = q - buf;
00653         /* data len */
00654         len = TS_PACKET_SIZE - header_len;
00655         if (len > payload_size)
00656             len = payload_size;
00657         stuffing_len = TS_PACKET_SIZE - header_len - len;
00658         if (stuffing_len > 0) {
00659             /* add stuffing with AFC */
00660             if (buf[3] & 0x20) {
00661                 /* stuffing already present: increase its size */
00662                 afc_len = buf[4] + 1;
00663                 memmove(buf + 4 + afc_len + stuffing_len,
00664                         buf + 4 + afc_len,
00665                         header_len - (4 + afc_len));
00666                 buf[4] += stuffing_len;
00667                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
00668             } else {
00669                 /* add stuffing */
00670                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
00671                 buf[3] |= 0x20;
00672                 buf[4] = stuffing_len - 1;
00673                 if (stuffing_len >= 2) {
00674                     buf[5] = 0x00;
00675                     memset(buf + 6, 0xff, stuffing_len - 2);
00676                 }
00677             }
00678         }
00679         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
00680         payload += len;
00681         payload_size -= len;
00682         put_buffer(s->pb, buf, TS_PACKET_SIZE);
00683         ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
00684     }
00685     put_flush_packet(s->pb);
00686 }
00687 
00688 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
00689 {
00690     AVStream *st = s->streams[pkt->stream_index];
00691     int size= pkt->size;
00692     uint8_t *buf= pkt->data;
00693     uint8_t *data= NULL;
00694     MpegTSWriteStream *ts_st = st->priv_data;
00695     int len, max_payload_size;
00696     const uint8_t *access_unit_index = NULL;
00697     const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
00698     int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
00699 
00700     if (pkt->pts != AV_NOPTS_VALUE)
00701         pts = pkt->pts + delay;
00702     if (pkt->dts != AV_NOPTS_VALUE)
00703         dts = pkt->dts + delay;
00704 
00705     if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
00706         /* for subtitle, a single PES packet must be generated */
00707         mpegts_write_pes(s, st, buf, size, pts, AV_NOPTS_VALUE);
00708         return 0;
00709     }
00710 
00711     if (st->codec->codec_id == CODEC_ID_DIRAC) {
00712         /* for Dirac, a single PES packet must be generated */
00713         mpegts_write_pes(s, st, buf, size, pts, dts);
00714         return 0;
00715     }
00716     max_payload_size = DEFAULT_PES_PAYLOAD_SIZE;
00717     if (st->codec->codec_id == CODEC_ID_MPEG2VIDEO ||
00718         st->codec->codec_id == CODEC_ID_MPEG1VIDEO) {
00719         const uint8_t *p = pkt->data;
00720         const uint8_t *end = pkt->data+pkt->size;
00721         uint32_t state = -1;
00722         while (p < end) {
00723             p = ff_find_start_code(p, end, &state);
00724             if (state == PICTURE_START_CODE) {
00725                 access_unit_index = p - 4;
00726                 break;
00727             }
00728         }
00729     } if (st->codec->codec_id == CODEC_ID_H264) {
00730         if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
00731             av_log(s, AV_LOG_ERROR, "h264 bitstream malformated\n");
00732             return -1;
00733         }
00734         if (pkt->data[4] != 0x09) { // AUD NAL
00735             data = av_malloc(pkt->size+6);
00736             if (!data)
00737                 return -1;
00738             memcpy(data+6, pkt->data, pkt->size);
00739             AV_WB32(data, 0x00000001);
00740             data[4] = 0x09;
00741             data[5] = 0xe0; // any slice type
00742             buf  = data;
00743             size = pkt->size+6;
00744         }
00745         access_unit_index = buf;
00746     } else {
00747         access_unit_index = pkt->data;
00748     }
00749 
00750     if (!access_unit_index) {
00751         av_log(s, AV_LOG_ERROR, "error, could not find access unit start\n");
00752         return -1;
00753     }
00754 
00755     while (size > 0) {
00756         len = max_payload_size - ts_st->payload_index;
00757         if (len > size)
00758             len = size;
00759         memcpy(ts_st->payload + ts_st->payload_index, buf, len);
00760         buf += len;
00761         size -= len;
00762         ts_st->payload_index += len;
00763         if (access_unit_index && access_unit_index < buf &&
00764             ts_st->payload_pts == AV_NOPTS_VALUE &&
00765             ts_st->payload_dts == AV_NOPTS_VALUE) {
00766             ts_st->payload_dts = dts;
00767             ts_st->payload_pts = pts;
00768         }
00769         if (ts_st->payload_index >= max_payload_size) {
00770             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
00771                              ts_st->payload_pts, ts_st->payload_dts);
00772             ts_st->payload_pts = AV_NOPTS_VALUE;
00773             ts_st->payload_dts = AV_NOPTS_VALUE;
00774             ts_st->payload_index = 0;
00775             access_unit_index = NULL; // unset access unit to avoid setting pts/dts again
00776         }
00777     }
00778 
00779     av_free(data);
00780 
00781     return 0;
00782 }
00783 
00784 static int mpegts_write_end(AVFormatContext *s)
00785 {
00786     MpegTSWrite *ts = s->priv_data;
00787     MpegTSWriteStream *ts_st;
00788     MpegTSService *service;
00789     AVStream *st;
00790     int i;
00791 
00792     /* flush current packets */
00793     for(i = 0; i < s->nb_streams; i++) {
00794         st = s->streams[i];
00795         ts_st = st->priv_data;
00796         if (ts_st->payload_index > 0) {
00797             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
00798                              ts_st->payload_pts, ts_st->payload_dts);
00799         }
00800     }
00801     put_flush_packet(s->pb);
00802 
00803     for(i = 0; i < ts->nb_services; i++) {
00804         service = ts->services[i];
00805         av_freep(&service->provider_name);
00806         av_freep(&service->name);
00807         av_free(service);
00808     }
00809     av_free(ts->services);
00810 
00811     return 0;
00812 }
00813 
00814 AVOutputFormat mpegts_muxer = {
00815     "mpegts",
00816     NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
00817     "video/x-mpegts",
00818     "ts,m2t",
00819     sizeof(MpegTSWrite),
00820     CODEC_ID_MP2,
00821     CODEC_ID_MPEG2VIDEO,
00822     mpegts_write_header,
00823     mpegts_write_packet,
00824     mpegts_write_end,
00825 };