mpegtsenc.c的源码

mpegtsenc.c的源码，如下：

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/*** MPEG2 transport stream (aka DVB) muxer* Copyright (c) 2003 Fabrice Bellard** This file is part of FFmpeg.** FFmpeg is free software; you can redistribute it and/or* modify it under the terms of the GNU Lesser General Public* License as published by the Free Software Foundation; either* version 2.1 of the License, or (at your option) any later version.** FFmpeg is distributed in the hope that it will be useful,* but WITHOUT ANY WARRANTY; without even the implied warranty of* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU* Lesser General Public License for more details.** You should have received a copy of the GNU Lesser General Public* License along with FFmpeg; if not, write to the Free Software* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA*/#include "libavutil/bswap.h"
#include "libavutil/crc.h"
#include "libavcodec/mpegvideo.h"
#include "avformat.h"
#include "internal.h"
#include "mpegts.h"
#include "adts.h"#define PCR_TIME_BASE 27000000/** write DVB SI sections *//**********************************************/
/** mpegts section writer */typedef struct MpegTSSection {int pid;int cc;void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);void *opaque;
} MpegTSSection;typedef struct MpegTSService {MpegTSSection pmt; /** MPEG2 pmt table context */int sid;           /** service ID */char *name;char *provider_name;int pcr_pid;int pcr_packet_count;int pcr_packet_period;
} MpegTSService;typedef struct MpegTSWrite {MpegTSSection pat; /** MPEG2 pat table */MpegTSSection sdt; /** MPEG2 sdt table context */MpegTSService **services;int sdt_packet_count;int sdt_packet_period;int pat_packet_count;int pat_packet_period;int nb_services;int onid;int tsid;int64_t first_pcr;int mux_rate; ///< set to 1 when VBR
} MpegTSWrite;/** NOTE: 4 bytes must be left at the end for the crc32 */
static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
{MpegTSWrite *ts = ((AVFormatContext*)s->opaque)->priv_data;unsigned int crc;unsigned char packet[TS_PACKET_SIZE];const unsigned char *buf_ptr;unsigned char *q;int first, b, len1, left;crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));buf[len - 4] = (crc >> 24) & 0xff;buf[len - 3] = (crc >> 16) & 0xff;buf[len - 2] = (crc >> 8) & 0xff;buf[len - 1] = (crc) & 0xff;/** send each packet */buf_ptr = buf;while (len > 0) {first = (buf == buf_ptr);q = packet;*q++ = 0x47;b = (s->pid >> 8);if (first)b |= 0x40;*q++ = b;*q++ = s->pid;s->cc = (s->cc + 1) & 0xf;*q++ = 0x10 | s->cc;if (first)*q++ = 0; /** 0 offset */len1 = TS_PACKET_SIZE - (q - packet);if (len1 > len)len1 = len;memcpy(q, buf_ptr, len1);q += len1;/** add known padding data */left = TS_PACKET_SIZE - (q - packet);if (left > 0)memset(q, 0xff, left);s->write_packet(s, packet);buf_ptr += len1;len -= len1;}
}static inline void put16(uint8_t **q_ptr, int val)
{uint8_t *q;q = *q_ptr;*q++ = val >> 8;*q++ = val;*q_ptr = q;
}static int mpegts_write_section1(MpegTSSection *s, int tid, int id,int version, int sec_num, int last_sec_num,uint8_t *buf, int len)
{uint8_t section[1024], *q;unsigned int tot_len;tot_len = 3 + 5 + len + 4;/** check if not too big */if (tot_len > 1024)return -1;q = section;*q++ = tid;put16(&q, 0xb000 | (len + 5 + 4)); /** 5 byte header + 4 byte CRC */put16(&q, id);*q++ = 0xc1 | (version << 1); /** current_next_indicator = 1 */*q++ = sec_num;*q++ = last_sec_num;memcpy(q, buf, len);mpegts_write_section(s, section, tot_len);return 0;
}/**********************************************/
/** mpegts writer */#define DEFAULT_PMT_START_PID   0x1000
#define DEFAULT_START_PID       0x0100
#define DEFAULT_PROVIDER_NAME   "FFmpeg"
#define DEFAULT_SERVICE_NAME    "Service01"/** default network id, transport stream and service identifiers */
#define DEFAULT_ONID            0x0001
#define DEFAULT_TSID            0x0001
#define DEFAULT_SID             0x0001/** a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
#define DEFAULT_PES_HEADER_FREQ 16
#define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)/** we retransmit the SI info at this rate */
#define SDT_RETRANS_TIME 500
#define PAT_RETRANS_TIME 100
#define PCR_RETRANS_TIME 20typedef struct MpegTSWriteStream {struct MpegTSService *service;int pid; /** stream associated pid */int cc;int payload_index;int first_pts_check; ///< first pts check neededint64_t payload_pts;int64_t payload_dts;uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];ADTSContext *adts;
} MpegTSWriteStream;static void mpegts_write_pat(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;MpegTSService *service;uint8_t data[1012], *q;int i;q = data;for(i = 0; i < ts->nb_services; i++) {service = ts->services[i];put16(&q, service->sid);put16(&q, 0xe000 | service->pmt.pid);}mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,data, q - data);
}static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
{//    MpegTSWrite *ts = s->priv_data;uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;int val, stream_type, i;q = data;put16(&q, 0xe000 | service->pcr_pid);program_info_length_ptr = q;q += 2; /** patched after *//** put program info here */val = 0xf000 | (q - program_info_length_ptr - 2);program_info_length_ptr[0] = val >> 8;program_info_length_ptr[1] = val;for(i = 0; i < s->nb_streams; i++) {AVStream *st = s->streams[i];MpegTSWriteStream *ts_st = st->priv_data;AVMetadataTag *lang = av_metadata_get(st->metadata, "language", NULL,0);switch(st->codec->codec_id) {case CODEC_ID_MPEG1VIDEO:case CODEC_ID_MPEG2VIDEO:stream_type = STREAM_TYPE_VIDEO_MPEG2;break;case CODEC_ID_MPEG4:stream_type = STREAM_TYPE_VIDEO_MPEG4;break;case CODEC_ID_H264:stream_type = STREAM_TYPE_VIDEO_H264;break;case CODEC_ID_DIRAC:stream_type = STREAM_TYPE_VIDEO_DIRAC;break;case CODEC_ID_MP2:case CODEC_ID_MP3:stream_type = STREAM_TYPE_AUDIO_MPEG1;break;case CODEC_ID_AAC:stream_type = STREAM_TYPE_AUDIO_AAC;break;case CODEC_ID_AC3:stream_type = STREAM_TYPE_AUDIO_AC3;break;default:stream_type = STREAM_TYPE_PRIVATE_DATA;break;}*q++ = stream_type;put16(&q, 0xe000 | ts_st->pid);desc_length_ptr = q;q += 2; /** patched after *//** write optional descriptors here */switch(st->codec->codec_type) {case AVMEDIA_TYPE_AUDIO:if (lang && strlen(lang->value) == 3) {*q++ = 0x0a; /** ISO 639 language descriptor */*q++ = 4;*q++ = lang->value[0];*q++ = lang->value[1];*q++ = lang->value[2];*q++ = 0; /** undefined type */}break;case AVMEDIA_TYPE_SUBTITLE:{const char *language;language = lang && strlen(lang->value)==3 ? lang->value : "eng";*q++ = 0x59;*q++ = 8;*q++ = language[0];*q++ = language[1];*q++ = language[2];*q++ = 0x10; /** normal subtitles (0x20 = if hearing pb) */if(st->codec->extradata_size == 4) {memcpy(q, st->codec->extradata, 4);q += 4;} else {put16(&q, 1); /** page id */put16(&q, 1); /** ancillary page id */}}break;case AVMEDIA_TYPE_VIDEO:if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {*q++ = 0x05; /**MPEG-2 registration descriptor*/*q++ = 4;*q++ = 'd';*q++ = 'r';*q++ = 'a';*q++ = 'c';}break;}val = 0xf000 | (q - desc_length_ptr - 2);desc_length_ptr[0] = val >> 8;desc_length_ptr[1] = val;}mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,data, q - data);
}/** NOTE: str == NULL is accepted for an empty string */
static void putstr8(uint8_t **q_ptr, const char *str)
{uint8_t *q;int len;q = *q_ptr;if (!str)len = 0;elselen = strlen(str);*q++ = len;memcpy(q, str, len);q += len;*q_ptr = q;
}static void mpegts_write_sdt(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;MpegTSService *service;uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;int i, running_status, free_ca_mode, val;q = data;put16(&q, ts->onid);*q++ = 0xff;for(i = 0; i < ts->nb_services; i++) {service = ts->services[i];put16(&q, service->sid);*q++ = 0xfc | 0x00; /** currently no EIT info */desc_list_len_ptr = q;q += 2;running_status = 4; /** running */free_ca_mode = 0;/** write only one descriptor for the service name and provider */*q++ = 0x48;desc_len_ptr = q;q++;*q++ = 0x01; /** digital television service */putstr8(&q, service->provider_name);putstr8(&q, service->name);desc_len_ptr[0] = q - desc_len_ptr - 1;/** fill descriptor length */val = (running_status << 13) | (free_ca_mode << 12) |(q - desc_list_len_ptr - 2);desc_list_len_ptr[0] = val >> 8;desc_list_len_ptr[1] = val;}mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,data, q - data);
}static MpegTSService *mpegts_add_service(MpegTSWrite *ts,int sid,const char *provider_name,const char *name)
{MpegTSService *service;service = av_mallocz(sizeof(MpegTSService));if (!service)return NULL;service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;service->sid = sid;service->provider_name = av_strdup(provider_name);service->name = av_strdup(name);service->pcr_pid = 0x1fff;dynarray_add(&ts->services, &ts->nb_services, service);return service;
}static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
{AVFormatContext *ctx = s->opaque;put_buffer(ctx->pb, packet, TS_PACKET_SIZE);
}static int mpegts_write_header(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;MpegTSWriteStream *ts_st;MpegTSService *service;AVStream *st, *pcr_st = NULL;AVMetadataTag *title;int i, j;const char *service_name;int *pids;ts->tsid = DEFAULT_TSID;ts->onid = DEFAULT_ONID;/** allocate a single DVB service */title = av_metadata_get(s->metadata, "title", NULL, 0);service_name = title ? title->value : DEFAULT_SERVICE_NAME;service = mpegts_add_service(ts, DEFAULT_SID,DEFAULT_PROVIDER_NAME, service_name);service->pmt.write_packet = section_write_packet;service->pmt.opaque = s;service->pmt.cc = 15;ts->pat.pid = PAT_PID;ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we writets->pat.write_packet = section_write_packet;ts->pat.opaque = s;ts->sdt.pid = SDT_PID;ts->sdt.cc = 15;ts->sdt.write_packet = section_write_packet;ts->sdt.opaque = s;pids = av_malloc(s->nb_streams * sizeof(*pids));if (!pids)return AVERROR(ENOMEM);/** assign pids to each stream */for(i = 0;i < s->nb_streams; i++) {st = s->streams[i];ts_st = av_mallocz(sizeof(MpegTSWriteStream));if (!ts_st)goto fail;st->priv_data = ts_st;ts_st->service = service;/** MPEG pid values < 16 are reserved. Applications which set st->id in* this range are assigned a calculated pid. */if (st->id < 16) {ts_st->pid = DEFAULT_START_PID + i;} else if (st->id < 0x1FFF) {ts_st->pid = st->id;} else {av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);goto fail;}if (ts_st->pid == service->pmt.pid) {av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);goto fail;}for (j = 0; j < i; j++)if (pids[j] == ts_st->pid) {av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);goto fail;}pids[i] = ts_st->pid;ts_st->payload_pts = AV_NOPTS_VALUE;ts_st->payload_dts = AV_NOPTS_VALUE;ts_st->first_pts_check = 1;ts_st->cc = 15;/** update PCR pid by using the first video stream */if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&service->pcr_pid == 0x1fff) {service->pcr_pid = ts_st->pid;pcr_st = st;}if (st->codec->codec_id == CODEC_ID_AAC &&st->codec->extradata_size > 0) {ts_st->adts = av_mallocz(sizeof(*ts_st->adts));if (!ts_st->adts)return AVERROR(ENOMEM);if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,st->codec->extradata_size) < 0)return -1;}}av_free(pids);/** if no video stream, use the first stream as PCR */if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {pcr_st = s->streams[0];ts_st = pcr_st->priv_data;service->pcr_pid = ts_st->pid;}ts->mux_rate = s->mux_rate ? s->mux_rate : 1;if (ts->mux_rate > 1) {service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /(TS_PACKET_SIZE * 8 * 1000);ts->sdt_packet_period      = (ts->mux_rate * SDT_RETRANS_TIME) /(TS_PACKET_SIZE * 8 * 1000);ts->pat_packet_period      = (ts->mux_rate * PAT_RETRANS_TIME) /(TS_PACKET_SIZE * 8 * 1000);ts->first_pcr = av_rescale(s->max_delay, PCR_TIME_BASE, AV_TIME_BASE);} else {/** Arbitrary values, PAT/PMT could be written on key frames */ts->sdt_packet_period = 200;ts->pat_packet_period = 40;if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {if (!pcr_st->codec->frame_size) {av_log(s, AV_LOG_WARNING, "frame size not set\n");service->pcr_packet_period =pcr_st->codec->sample_rate/(10*512);} else {service->pcr_packet_period =pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);}} else {// max delta PCR 0.1sservice->pcr_packet_period =pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);}}// output a PCR as soon as possibleservice->pcr_packet_count = service->pcr_packet_period;ts->pat_packet_count = ts->pat_packet_period-1;ts->sdt_packet_count = ts->sdt_packet_period-1;if (ts->mux_rate == 1)av_log(s, AV_LOG_INFO, "muxrate VBR, ");elseav_log(s, AV_LOG_INFO, "muxrate %d, ", ts->mux_rate);av_log(s, AV_LOG_INFO, "pcr every %d pkts, ""sdt every %d, pat/pmt every %d pkts\n",service->pcr_packet_period,ts->sdt_packet_period, ts->pat_packet_period);put_flush_packet(s->pb);return 0;fail:av_free(pids);for(i = 0;i < s->nb_streams; i++) {st = s->streams[i];av_free(st->priv_data);}return -1;
}/** send SDT, PAT and PMT tables regulary */
static void retransmit_si_info(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;int i;if (++ts->sdt_packet_count == ts->sdt_packet_period) {ts->sdt_packet_count = 0;mpegts_write_sdt(s);}if (++ts->pat_packet_count == ts->pat_packet_period) {ts->pat_packet_count = 0;mpegts_write_pat(s);for(i = 0; i < ts->nb_services; i++) {mpegts_write_pmt(s, ts->services[i]);}}
}static int64_t get_pcr(const MpegTSWrite *ts, ByteIOContext *pb)
{return av_rescale(url_ftell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +ts->first_pcr;
}static uint8_t* write_pcr_bits(uint8_t *buf, int64_t pcr)
{int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;*buf++ = pcr_high >> 25;*buf++ = pcr_high >> 17;*buf++ = pcr_high >> 9;*buf++ = pcr_high >> 1;*buf++ = ((pcr_high & 1) << 7) | (pcr_low >> 8);*buf++ = pcr_low;return buf;
}/** Write a single null transport stream packet */
static void mpegts_insert_null_packet(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;uint8_t *q;uint8_t buf[TS_PACKET_SIZE];q = buf;*q++ = 0x47;*q++ = 0x00 | 0x1f;*q++ = 0xff;*q++ = 0x10;memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));put_buffer(s->pb, buf, TS_PACKET_SIZE);
}/** Write a single transport stream packet with a PCR and no payload */
static void mpegts_insert_pcr_only(AVFormatContext *s, AVStream *st)
{MpegTSWrite *ts = s->priv_data;MpegTSWriteStream *ts_st = st->priv_data;uint8_t *q;uint8_t buf[TS_PACKET_SIZE];q = buf;*q++ = 0x47;*q++ = ts_st->pid >> 8;*q++ = ts_st->pid;*q++ = 0x20 | ts_st->cc;   /** Adaptation only *//** Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */*q++ = TS_PACKET_SIZE - 5; /** Adaptation Field Length */*q++ = 0x10;               /** Adaptation flags: PCR present *//** PCR coded into 6 bytes */q = write_pcr_bits(q, get_pcr(ts, s->pb));/** stuffing bytes */memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));put_buffer(s->pb, buf, TS_PACKET_SIZE);
}static void write_pts(uint8_t *q, int fourbits, int64_t pts)
{int val;val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;*q++ = val;val = (((pts >> 15) & 0x7fff) << 1) | 1;*q++ = val >> 8;*q++ = val;val = (((pts) & 0x7fff) << 1) | 1;*q++ = val >> 8;*q++ = val;
}/** Add a pes header to the front of payload, and segment into an integer number of* ts packets. The final ts packet is padded using an over-sized adaptation header* to exactly fill the last ts packet.* NOTE: 'payload' contains a complete PES payload.*/
static void mpegts_write_pes(AVFormatContext *s, AVStream *st,const uint8_t *payload, int payload_size,int64_t pts, int64_t dts)
{MpegTSWriteStream *ts_st = st->priv_data;MpegTSWrite *ts = s->priv_data;uint8_t buf[TS_PACKET_SIZE];uint8_t *q;int val, is_start, len, header_len, write_pcr, private_code, flags;int afc_len, stuffing_len;int64_t pcr = -1; /** avoid warning */int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);is_start = 1;while (payload_size > 0) {retransmit_si_info(s);write_pcr = 0;if (ts_st->pid == ts_st->service->pcr_pid) {if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on framests_st->service->pcr_packet_count++;if (ts_st->service->pcr_packet_count >=ts_st->service->pcr_packet_period) {ts_st->service->pcr_packet_count = 0;write_pcr = 1;}}if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&(dts - get_pcr(ts, s->pb)/300) > delay) {/** pcr insert gets priority over null packet insert */if (write_pcr)mpegts_insert_pcr_only(s, st);elsempegts_insert_null_packet(s);continue; /** recalculate write_pcr and possibly retransmit si_info */}/** prepare packet header */q = buf;*q++ = 0x47;val = (ts_st->pid >> 8);if (is_start)val |= 0x40;*q++ = val;*q++ = ts_st->pid;ts_st->cc = (ts_st->cc + 1) & 0xf;*q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);if (write_pcr) {// add 11, pcr references the last byte of program clock reference baseif (ts->mux_rate > 1)pcr = get_pcr(ts, s->pb);elsepcr = (dts - delay)*300;if (dts != AV_NOPTS_VALUE && dts < pcr / 300)av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");*q++ = 7; /** AFC length */*q++ = 0x10; /** flags: PCR present */q = write_pcr_bits(q, pcr);}if (is_start) {int pes_extension = 0;/** write PES header */*q++ = 0x00;*q++ = 0x00;*q++ = 0x01;private_code = 0;if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {if (st->codec->codec_id == CODEC_ID_DIRAC) {*q++ = 0xfd;} else*q++ = 0xe0;} else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&(st->codec->codec_id == CODEC_ID_MP2 ||st->codec->codec_id == CODEC_ID_MP3)) {*q++ = 0xc0;} else {*q++ = 0xbd;if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {private_code = 0x20;}}header_len = 0;flags = 0;if (pts != AV_NOPTS_VALUE) {header_len += 5;flags |= 0x80;}if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {header_len += 5;flags |= 0x40;}if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&st->codec->codec_id == CODEC_ID_DIRAC) {/** set PES_extension_flag */pes_extension = 1;flags |= 0x01;/*** One byte for PES2 extension flag +* one byte for extension length +* one byte for extension id*/header_len += 3;}len = payload_size + header_len + 3;if (private_code != 0)len++;if (len > 0xffff)len = 0;*q++ = len >> 8;*q++ = len;val = 0x80;/** data alignment indicator is required for subtitle data */if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE)val |= 0x04;*q++ = val;*q++ = flags;*q++ = header_len;if (pts != AV_NOPTS_VALUE) {write_pts(q, flags >> 6, pts);q += 5;}if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {write_pts(q, 1, dts);q += 5;}if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {flags = 0x01;  /** set PES_extension_flag_2 */*q++ = flags;*q++ = 0x80 | 0x01;  /** marker bit + extension length *//*** Set the stream id extension flag bit to 0 and* write the extended stream id*/*q++ = 0x00 | 0x60;}if (private_code != 0)*q++ = private_code;is_start = 0;}/** header size */header_len = q - buf;/** data len */len = TS_PACKET_SIZE - header_len;if (len > payload_size)len = payload_size;stuffing_len = TS_PACKET_SIZE - header_len - len;if (stuffing_len > 0) {/** add stuffing with AFC */if (buf[3] & 0x20) {/** stuffing already present: increase its size */afc_len = buf[4] + 1;memmove(buf + 4 + afc_len + stuffing_len,buf + 4 + afc_len,header_len - (4 + afc_len));buf[4] += stuffing_len;memset(buf + 4 + afc_len, 0xff, stuffing_len);} else {/** add stuffing */memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);buf[3] |= 0x20;buf[4] = stuffing_len - 1;if (stuffing_len >= 2) {buf[5] = 0x00;memset(buf + 6, 0xff, stuffing_len - 2);}}}memcpy(buf + TS_PACKET_SIZE - len, payload, len);payload += len;payload_size -= len;put_buffer(s->pb, buf, TS_PACKET_SIZE);}put_flush_packet(s->pb);
}static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
{AVStream *st = s->streams[pkt->stream_index];int size = pkt->size;uint8_t *buf= pkt->data;uint8_t *data= NULL;MpegTSWriteStream *ts_st = st->priv_data;const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;if (pkt->pts != AV_NOPTS_VALUE)pts = pkt->pts + delay;if (pkt->dts != AV_NOPTS_VALUE)dts = pkt->dts + delay;if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {av_log(s, AV_LOG_ERROR, "first pts value must set\n");return -1;}ts_st->first_pts_check = 0;if (st->codec->codec_id == CODEC_ID_H264) {const uint8_t *p = buf, *buf_end = p+size;uint32_t state = -1;if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {av_log(s, AV_LOG_ERROR, "h264 bitstream malformated, ""no startcode found, use -vbsf h264_mp4toannexb\n");return -1;}do {p = ff_find_start_code(p, buf_end, &state);//av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);} while (p < buf_end && (state & 0x1f) != 9 &&(state & 0x1f) != 5 && (state & 0x1f) != 1);if ((state & 0x1f) != 9) { // AUD NALdata = av_malloc(pkt->size+6);if (!data)return -1;memcpy(data+6, pkt->data, pkt->size);AV_WB32(data, 0x00000001);data[4] = 0x09;data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bitbuf  = data;size = pkt->size+6;}} else if (st->codec->codec_id == CODEC_ID_AAC) {if (pkt->size < 2)return -1;if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {ADTSContext *adts = ts_st->adts;int new_size;if (!adts) {av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format ""and extradata missing\n");return -1;}new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;if ((unsigned)new_size >= INT_MAX)return -1;data = av_malloc(new_size);if (!data)return AVERROR(ENOMEM);ff_adts_write_frame_header(adts, data, pkt->size, adts->pce_size);if (adts->pce_size) {memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);adts->pce_size = 0;}memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);buf = data;size = new_size;}}if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {// for video and subtitle, write a single pes packetmpegts_write_pes(s, st, buf, size, pts, dts);av_free(data);return 0;}if (ts_st->payload_index + size > DEFAULT_PES_PAYLOAD_SIZE) {mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,ts_st->payload_pts, ts_st->payload_dts);ts_st->payload_index = 0;}if (!ts_st->payload_index) {ts_st->payload_pts = pts;ts_st->payload_dts = dts;}memcpy(ts_st->payload + ts_st->payload_index, buf, size);ts_st->payload_index += size;av_free(data);return 0;
}static int mpegts_write_end(AVFormatContext *s)
{MpegTSWrite *ts = s->priv_data;MpegTSWriteStream *ts_st;MpegTSService *service;AVStream *st;int i;/** flush current packets */for(i = 0; i < s->nb_streams; i++) {st = s->streams[i];ts_st = st->priv_data;if (ts_st->payload_index > 0) {mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,ts_st->payload_pts, ts_st->payload_dts);}av_freep(&ts_st->adts);}put_flush_packet(s->pb);for(i = 0; i < ts->nb_services; i++) {service = ts->services[i];av_freep(&service->provider_name);av_freep(&service->name);av_free(service);}av_free(ts->services);return 0;
}AVOutputFormat mpegts_muxer = {"mpegts",NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),"video/x-mpegts","ts,m2t",sizeof(MpegTSWrite),CODEC_ID_MP2,CODEC_ID_MPEG2VIDEO,mpegts_write_header,mpegts_write_packet,mpegts_write_end,
};

结束...................

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