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对TS流的分析， 涉及到对PAT，PMT等等的分析， 具体内容见iso/iec 13838系列文档，

本文只给出自己写的一些和TS分析想关的代码， 简单的分析足够了， 不考虑复杂情况：

//////////////////////////////////////////////////////////////////////////<br /> //<br /> // TS流结构定义<br /> //<br /> //////////////////////////////////////////////////////////////////////////</p> <p>#ifndef ZZQ_TS_H_<br /> #define ZZQ_TS_H_</p> <p>#include <vector><br /> using namespace std;<br /> typedef unsigned char byte;<br /> typedef unsigned int bits;</p> <p>#define TSPKT_LENGTH 188</p> <p>//-----------------------------------------------------------------------------<br /> // 结构体<br /> //-----------------------------------------------------------------------------<br /> // TS包构成伪代码<br /> /*<br /> transport_packet()<br /> {<br /> sync_byte<br /> transport_error_indicator<br /> payload_unit_start_indicator<br /> transport_priority<br /> PID<br /> transport_scrambling_control<br /> adaptation_field_control<br /> continuity_counter<br /> if(adaptation_field_control=='10' || adaptation_field_control=='11')<br /> {<br /> adaptation_field()<br /> }<br /> if(adaptation_field_control=='01' || adaptation_field_control=='11')<br /> {<br /> for (i=0;i<N;i++)<br /> {<br /> data_byte<br /> }<br /> }<br /> }<br /> */<br /> // TS包头部<br /> // WARNING!!! 暂时没有考虑修改区以及修改区内可选字段的处理<br /> struct ts_header<br /> {<br /> bits sync_byte : 8;<br /> bits transport_error_indicator : 1;<br /> bits payload_unit_start_indicator : 1;<br /> bits transport_priority : 1;<br /> bits PID : 13;<br /> bits transport_scrambling_control : 2;<br /> bits adaptation_field_control : 2;<br /> bits continuity_counter : 4;<br /> };<br /> // TS包中的修改字段(adaptation field)<br /> struct ts_adaptation_field<br /> {<br /> bits adaptation_field_length : 8;<br /> bits discontinuity_idicator : 1;<br /> bits random_access_indicator : 1;<br /> bits elementary_stream_priority_indicator : 1;<br /> bits flags : 5; // 5 flags<br /> };</p> <p>// PAT中的可变段<br /> struct ts_pat_section<br /> {<br /> bits program_number : 16;<br /> bits reserved : 3;<br /> bits PID : 13;<br /> };<br /> typedef vector<ts_pat_section> vec_pat_section;<br /> // PAT表, P138-PAT的结构, 文档P61<br /> struct ts_pat<br /> {<br /> bits table_id : 8; // 0x00<br /> bits section_syntax_indicator : 1; // 1<br /> bits zero : 1; // 0<br /> bits reserved_1 : 2; // 11<br /> bits section_length : 12;<br /> bits transport_stream_id : 16; // 传输数据流识别<br /> bits reserved_2 : 2; // "11"<br /> bits version_number : 5;<br /> bits current_next_indicator : 1;<br /> bits section_number : 8;<br /> bits last_section_number : 8;<br /> // .... TODO<br /> vec_pat_section network_section;<br /> vec_pat_section pmt_section;<br /> bits crc32 : 32;<br /> };</p> <p>// Stream_type分配表, P85<br /> #define ST_Reserved 0x00 // ITU-T | ISO/IEC Reserved<br /> #define ST_VIDEO_1 0x01 // ISO/IEC 11172 Video<br /> #define ST_VIDEO_2 0x02 // ITU-T Rec. H.262 | ISO/IEC 13818-2 Video or ISO/IEC 11172-2 constrained parameter video stream<br /> #define ST_AUDIO_1 0x03 // ISO/IEC 11172 Audio<br /> #define ST_AUDIO_2 0x04 // ISO/IEC 13818-3 Audio<br /> #define ST_PRIVATE_SECTIONS 0x05 // ITU-T Rec. H.222.0 | ISO/IEC 13818-1 private_sections<br /> #define ST_PES_PKT_PRIVATE_DATA 0x06 // ITU-T Rec. H.222.0 | ISO/IEC 13818-1 PES packets containing private data<br /> #define ST_MHEG 0x07 // ISO/IEC 13522 MHEG<br /> #define ST_DSMCC 0x08 // ITU-T Rec. H.222.0 | ISO/IEC 13818-1 Annex A DSM CC<br /> #define ST_H2221 0x09 // ITU-T Rec. H.222.1<br /> #define ST_TYPEA 0x0A // ISO/IEC 13818-6 type A<br /> #define ST_TYPEB 0x0B // ISO/IEC 13818-6 type B<br /> #define ST_TYPEC 0x0C // ISO/IEC 13818-6 type C<br /> #define ST_TYPED 0x0D // ISO/IEC 13818-6 type D<br /> #define ST_AUXILIARY 0x0E // ISO/IEC 13818-1 auxiliary<br /> // 0x0F-0x7F: ITU-T Rec. H.222.0 | ISO/IEC 13818-1 Reserved<br /> // 0x80-0xFF: User Private<br /> // PMT表中的ES段<br /> struct ts_pmt_es_section<br /> {<br /> bits stream_type : 8;<br /> bits reserved_1 : 3;<br /> bits elementary_PID : 13;<br /> bits reserved_2 : 4;<br /> bits ES_info_length : 12;<br /> };<br /> typedef vector<ts_pmt_es_section> vec_pmt_section;</p> <p>// PMT表, 书P138 - PMT的结构<br /> struct ts_pmt<br /> {<br /> bits table_id : 8; // 0x02<br /> bits section_syntax_indicator : 1; // 1<br /> bits zero : 1; // 0<br /> bits reserved_1 : 2; // 11<br /> bits section_length : 12;<br /> bits program_number : 16;<br /> bits reserved_2 : 2; // 11<br /> bits version_number : 5;<br /> bits current_next_indicator : 1;<br /> bits section_number : 8;<br /> bits last_section_number : 8;<br /> bits reserved_3 : 3; // 111<br /> bits PCR_PID : 13;<br /> bits reserved_4 : 4; // 1111<br /> bits program_info_length : 12;<br /> vec_pmt_section es_section;<br /> bits crc32 : 32;<br /> };</p> <p>// PES包构成伪代码 P43<br /> /*<br /> 太长，略<br /> */</p> <p>// Steam ID分配表, 文档P47<br /> #define SID_PROGRAM_STREAM_MAP 0xBC<br /> #define SID_PRIVATE_STREAM_1 0xBD<br /> #define SID_PADDING_STREAM 0xBE<br /> #define SID_PRIVATE_STREAM_2 0xBF<br /> #define SID_AUDIO_STREAM 0xC0 // 110x xxxx, stream number x xxxx<br /> #define SID_VIDEO_STREAM 0xE0 // 1110 xxxx, stream number xxxx<br /> #define SID_ECM_STREAM 0xF0<br /> #define SID_EMM_STREAM 0xF1<br /> #define SID_DSMCC_STREAM 0xF2<br /> #define SID_13522_STREAM 0xF3<br /> #define SID_TYPEA 0xF4<br /> #define SID_TYPEB 0xF5<br /> #define SID_TYPEC 0xF6<br /> #define SID_TYPED 0xF7<br /> #define SID_TYPEE 0xF8<br /> #define SID_ANCILLARY_STREAM 0xF9<br /> // 1111 1010 ~ 1111 1110, reserved data stream<br /> #define SID_PROGRAM_STREAM_DIRECTORY 0xFF</p> <p>// PES包中的可选包头部<br /> struct optional_pes_header<br /> {<br /> bits prefix : 2; // "10"<br /> bits pes_scrambling_control : 2;<br /> bits pes_priority : 1;<br /> bits data_alignment_indicator : 1;<br /> bits copyright : 1;<br /> bits original_or_copy : 1;<br /> // 7 flags start<br /> bits PTS_DTS_flags : 2;<br /> bits ESCR_flag : 1;<br /> bits ES_rate_flag : 1;<br /> bits DSM_trick_mode_flag : 1;<br /> bits additional_copy_info_flag: 1;<br /> bits PES_CRC_flag : 1;<br /> bits PES_extension_flag : 1;<br /> // 7 flags end<br /> bits pes_header_data_length : 8;<br /> // WARNING!!! 目前只使用 PTS, DTS<br /> bits PTS_H : 3; // 32..30<br /> bits PTS_M : 15; // 29..15<br /> bits PTS_L : 15; // 14..0<br /> bits DTS_H : 3; // 32..30<br /> bits DTS_M : 15; // 29..15<br /> bits DTS_L : 15; // 14..0<br /> };</p> <p>// PES包头部, 文档P43, 书P131<br /> struct pes_header<br /> {<br /> bits packet_start_code_prefix : 24;<br /> bits stream_id : 8;<br /> bits pes_packet_length : 16;<br /> // 之后是optional PES header, 即任意包头, 它的有无由stream_id决定<br /> bool ophdr_flag;<br /> optional_pes_header ophdr; // 如果声明为指针, 会带来一些内存问题<br /> //byte* es_data; // 实际数据指针<br /> int offset; // 实际数据偏移</p> <p> pes_header()<br /> {<br /> ophdr_flag = false;<br /> offset = -1;<br /> }<br /> ~pes_header()<br /> {}<br /> };</p> <p>//-----------------------------------------------------------------------------<br /> // 位段结构调整函数<br /> //-----------------------------------------------------------------------------<br /> int adjust_ts_header(ts_header* pkt, byte* buff);<br /> int adjust_ts_pat(ts_pat* pkt, byte* buff);<br /> int adjust_ts_pmt(ts_pmt* pkt, byte* buff);<br /> int adjust_ts_pes_header(pes_header* pkt, byte* buff);<br /> __int64 get_pts_from_pes(pes_header& pkt);<br /> __int64 get_dts_from_pes(pes_header& pkt);<br /> #endif 

//////////////////////////////////////////////////////////////////////////<br /> //<br /> // TS流相关函数<br /> //<br /> //////////////////////////////////////////////////////////////////////////<br /> #include <stdio.h><br /> #include "zzq_TS.h"</p> <p>int adjust_ts_header(ts_header* pkt, byte* buff)<br /> {<br /> if(pkt == NULL || buff == NULL)<br /> { return 1; }<br /> pkt->sync_byte = buff[0];<br /> pkt->transport_error_indicator = buff[1] >> 7;<br /> pkt->payload_unit_start_indicator = buff[1] >> 6 & 0x01;<br /> pkt->transport_priority = buff[1] >> 5 & 0x01;<br /> pkt->PID = (buff[1] & 0x1f)<<8 | buff[2];<br /> pkt->transport_scrambling_control = buff[3] >> 6;<br /> pkt->adaptation_field_control = buff[3] >> 4 & 0x03;<br /> pkt->continuity_counter = buff[3] & 0x03;<br /> return 0;<br /> }</p> <p>int adjust_ts_pat(ts_pat* pkt, byte* buff)<br /> {<br /> if(pkt == NULL || buff == NULL)<br /> { return 1; }<br /> pkt->table_id = buff[0];<br /> pkt->section_syntax_indicator = buff[1] >> 7;<br /> pkt->zero = buff[1] >> 6 & 0x1;<br /> pkt->reserved_1 = buff[1] >> 4 & 0x3;<br /> pkt->section_length = (buff[1] & 0x0f) << 8 | buff[2];<br /> pkt->transport_stream_id = buff[3] << 8 | buff[4];<br /> pkt->reserved_2 = buff[5] >> 6;<br /> pkt->version_number = buff[5] >> 1 & 0x1f;<br /> pkt->current_next_indicator = (buff[5] << 7) >> 7;<br /> pkt->section_number = buff[6];<br /> pkt->last_section_number = buff[7];<br /> // get crc32<br /> int len = 3 + pkt->section_length;<br /> pkt->crc32 = (buff[len-4] & 0x000000ff) << 24 |<br /> (buff[len-3] & 0x000000ff) << 16 |<br /> (buff[len-2] & 0x000000ff) << 8 |<br /> (buff[len-1] & 0x000000ff);<br /> // get variable section<br /> for(int i=0; i<pkt->section_length-4-8; i+=4 )<br /> {<br /> ts_pat_section sec;<br /> sec.program_number = buff[8+i] << 8 | buff[9];<br /> sec.reserved = buff[10+i] >> 5;<br /> sec.PID = (buff[10+i] << 3) << 5 | buff[11+i];<br /> if(sec.program_number == 0x0)<br /> pkt->network_section.push_back(sec);<br /> else<br /> pkt->pmt_section.push_back(sec);<br /> }<br /> return 0;<br /> }</p> <p>int adjust_ts_pmt(ts_pmt* pkt, byte* buff)<br /> {<br /> if(pkt == NULL || buff == NULL)<br /> { return 1; }<br /> pkt->table_id = buff[0];<br /> pkt->section_syntax_indicator = buff[1] >> 7;<br /> pkt->zero = buff[1] >> 6;<br /> pkt->reserved_1 = buff[1] >> 4;<br /> pkt->section_length = (buff[1] & 0x0f) << 8 | buff[2];<br /> pkt->program_number = buff[3] << 8 | buff[4];<br /> pkt->reserved_2 = buff[5] >> 6;<br /> pkt->version_number = buff[5] >> 1 & 0x1f;<br /> pkt->current_next_indicator = (buff[5] << 7) >> 7;<br /> pkt->section_number = buff[6];<br /> pkt->last_section_number = buff[7];<br /> pkt->reserved_3 = buff[8] >> 5;<br /> pkt->PCR_PID = ((buff[8] << 8) | buff[9]) & 0x1fff;<br /> pkt->reserved_4 = buff[10] >> 4;<br /> pkt->program_info_length = (buff[10] & 0x0f) << 8 | buff[11];<br /> // get crc32<br /> int len = pkt->section_length + 3;<br /> pkt->crc32 = (buff[len-4] & 0x000000ff) << 24 |<br /> (buff[len-3] & 0x000000ff) << 16 |<br /> (buff[len-2] & 0x000000ff) << 8 |<br /> (buff[len-1] & 0x000000ff);<br /> // skip program description<br /> int pos = 12 + pkt->program_info_length;<br /> for( ; pos <= (pkt->section_length-4); pos+=5)<br /> {<br /> ts_pmt_es_section sec;<br /> sec.stream_type = buff[pos];<br /> sec.reserved_1 = buff[pos+1] >> 5;<br /> sec.elementary_PID = ((buff[pos+1] << 8) | buff[pos+2]) & 0x1fff;<br /> sec.ES_info_length = (buff[pos+3] & 0x0f) << 8 | buff[pos+4];<br /> pkt->es_section.push_back(sec);<br /> pos += sec.ES_info_length;<br /> }<br /> return 0;<br /> }</p> <p>int adjust_ts_pes_header(pes_header* pkt, byte* buff)<br /> {<br /> if(pkt == NULL || buff == NULL)<br /> { return 1; }<br /> // 0000 0000 0000 0000 0000 0001 : 0x000001<br /> pkt->packet_start_code_prefix = (buff[0] & 0x0000ff) << 16 |<br /> (buff[1] & 0x0000ff) << 8 |<br /> (buff[2] & 0x0000ff);<br /> //if(pkt->packet_start_code_prefix != 0x000001) return 2;<br /> byte sid = buff[3]; // aux<br /> pkt->stream_id = buff[3];<br /> pkt->pes_packet_length = buff[4] << 8 | buff[5];<br /> if(sid != SID_PROGRAM_STREAM_MAP &&<br /> sid != SID_PADDING_STREAM &&<br /> sid != SID_PRIVATE_STREAM_2 &&<br /> sid != SID_ECM_STREAM &&<br /> sid != SID_EMM_STREAM &&<br /> sid != SID_PROGRAM_STREAM_DIRECTORY &&<br /> sid != SID_DSMCC_STREAM &&<br /> sid != SID_TYPEE<br /> )<br /> {<br /> pkt->ophdr_flag = true;<br /> pkt->ophdr.prefix = buff[6] >> 6; // "10" : 2<br /> //if(pkt->ophdr->prefix != 2) return 2;<br /> pkt->ophdr.pes_scrambling_control = buff[6] >> 4 & 0x03;<br /> pkt->ophdr.pes_priority = buff[6] >> 3 & 0x01;<br /> pkt->ophdr.data_alignment_indicator = buff[6] >> 2 & 0x01;<br /> pkt->ophdr.copyright = buff[6] >> 1 & 0x01;<br /> pkt->ophdr.original_or_copy = buff[6] & 0x01;<br /> pkt->ophdr.PTS_DTS_flags = buff[7] >> 6 & 0x03;<br /> pkt->ophdr.ESCR_flag = buff[7] >> 5 & 0x01;<br /> pkt->ophdr.ES_rate_flag = buff[7] >> 4 & 0x01;<br /> pkt->ophdr.DSM_trick_mode_flag = buff[7] >> 3 & 0x01;<br /> pkt->ophdr.additional_copy_info_flag = buff[7] >> 2 & 0x01;<br /> pkt->ophdr.PES_CRC_flag = buff[7] >> 1 & 0x01;<br /> pkt->ophdr.PES_extension_flag = buff[7] & 0x01;<br /> pkt->ophdr.pes_header_data_length = buff[8];<br /> if(pkt->ophdr.PTS_DTS_flags == 0x2) // "10"<br /> {<br /> // 以下移位操作, 都将各位串靠左对齐<br /> pkt->ophdr.PTS_H = buff[9] << 3 & 0xe0; // 3 bits<br /> pkt->ophdr.PTS_M = (buff[10] << 8) | (buff[11] & 0xfe); // 15 bits<br /> pkt->ophdr.PTS_L = (buff[12] << 8) | (buff[13] & 0xfe); // 15 bits<br /> }<br /> else if(pkt->ophdr.PTS_DTS_flags == 0x3) // "11"<br /> {<br /> // 以下移位操作, 都将各位串靠左对齐<br /> pkt->ophdr.PTS_H = buff[9] << 3 & 0xe0; // 3 bits<br /> pkt->ophdr.PTS_M = (buff[10] << 8) | (buff[11] & 0xfe); // 15 bits<br /> pkt->ophdr.PTS_L = (buff[12] << 8) | (buff[13] & 0xfe); // 15 bits<br /> pkt->ophdr.DTS_H = buff[14] << 3 & 0xe0;<br /> pkt->ophdr.DTS_M = (buff[15] << 8) | (buff[16] & 0xfe); // 15 bits<br /> pkt->ophdr.DTS_L = (buff[17] << 8) | (buff[18] & 0xfe); // 15 bits<br /> }<br /> //////////////////////////////////////////////////////////////////////////<br /> // ESCR, ES_rate之类的目前不处理<br /> // 6 + 3: (24+8+16) + (2+2+1+1+1+1+8+8)<br /> pkt->offset = 6 + 3 + pkt->ophdr.pes_header_data_length;<br /> }<br /> else if(sid == SID_PROGRAM_STREAM_MAP ||<br /> sid == SID_PRIVATE_STREAM_2 ||<br /> sid == SID_ECM_STREAM ||<br /> sid == SID_EMM_STREAM ||<br /> sid == SID_PROGRAM_STREAM_DIRECTORY ||<br /> sid == SID_DSMCC_STREAM ||<br /> sid == SID_TYPEE<br /> )<br /> {<br /> pkt->offset = 6;<br /> }<br /> else if(sid == SID_PADDING_STREAM)<br /> {<br /> pkt->offset = -1;<br /> }</p> <p> return 0;<br /> }</p> <p>__int64 get_pts_from_pes(pes_header& pkt)<br /> {<br /> if(pkt.ophdr_flag == false) return -1;<br /> if(pkt.ophdr.PTS_DTS_flags != 0x2 && pkt.ophdr.PTS_DTS_flags != 0x3)<br /> return -1;<br /> __int64 H = 0, M = 0, L = 0;<br /> L = pkt.ophdr.PTS_L >> 1 | pkt.ophdr.PTS_M << 14;<br /> M = pkt.ophdr.PTS_M >> 2 | pkt.ophdr.PTS_H << 13;<br /> L = pkt.ophdr.PTS_H >> 3;<br /> return (H<<32) | (M<<16) | L;<br /> }<br /> __int64 get_dts_from_pes(pes_header& pkt)<br /> {<br /> if(pkt.ophdr_flag == false) return -1;<br /> if(pkt.ophdr.PTS_DTS_flags != 0x3)<br /> return -1;<br /> __int64 H = 0, M = 0, L = 0;<br /> L = pkt.ophdr.DTS_L >> 1 | pkt.ophdr.DTS_M << 14;<br /> M = pkt.ophdr.DTS_M >> 2 | pkt.ophdr.DTS_H << 13;<br /> L = pkt.ophdr.DTS_H >> 3;<br /> return (H<<32) | (M<<16) | L;<br /> }