/* * MPEG2 transport stream (aka DVB) demuxer * Copyright (c) 2002-2003 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 */ //#define DEBUG //#define DEBUG_SEEK #include "libavutil/crc.h" #include "libavutil/intreadwrite.h" #include "libavcodec/bytestream.h" #include "avformat.h" #include "mpegts.h" #include "internal.h" #include "seek.h" /* 1.0 second at 24Mbit/s */ #define MAX_SCAN_PACKETS 32000 /* maximum size in which we look for synchronisation if synchronisation is lost */ #define MAX_RESYNC_SIZE 4096 #define MAX_PES_PAYLOAD 200*1024 typedef struct PESContext PESContext; static PESContext* add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type); enum MpegTSFilterType { MPEGTS_PES, MPEGTS_SECTION, }; typedef struct MpegTSFilter MpegTSFilter; typedef int PESCallback(MpegTSFilter *f, const uint8_t *buf, int len, int is_start, int64_t pos); typedef struct MpegTSPESFilter { PESCallback *pes_cb; void *opaque; } MpegTSPESFilter; typedef void SectionCallback(MpegTSFilter *f, const uint8_t *buf, int len); typedef void SetServiceCallback(void *opaque, int ret); typedef struct MpegTSSectionFilter { int section_index; int section_h_size; uint8_t *section_buf; unsigned int check_crc:1; unsigned int end_of_section_reached:1; SectionCallback *section_cb; void *opaque; } MpegTSSectionFilter; struct MpegTSFilter { int pid; int last_cc; /* last cc code (-1 if first packet) */ enum MpegTSFilterType type; union { MpegTSPESFilter pes_filter; MpegTSSectionFilter section_filter; } u; }; #define MAX_PIDS_PER_PROGRAM 64 struct Program { unsigned int id; //program id/service id unsigned int nb_pids; unsigned int pids[MAX_PIDS_PER_PROGRAM]; }; struct MpegTSContext { /* user data */ AVFormatContext *stream; /** raw packet size, including FEC if present */ int raw_packet_size; int pos47; /** if true, all pids are analyzed to find streams */ int auto_guess; /** compute exact PCR for each transport stream packet */ int mpeg2ts_compute_pcr; int64_t cur_pcr; /**< used to estimate the exact PCR */ int pcr_incr; /**< used to estimate the exact PCR */ /* data needed to handle file based ts */ /** stop parsing loop */ int stop_parse; /** packet containing Audio/Video data */ AVPacket *pkt; /** to detect seek */ int64_t last_pos; /******************************************/ /* private mpegts data */ /* scan context */ /** structure to keep track of Program->pids mapping */ unsigned int nb_prg; struct Program *prg; /** filters for various streams specified by PMT + for the PAT and PMT */ MpegTSFilter *pids[NB_PID_MAX]; }; /* TS stream handling */ enum MpegTSState { MPEGTS_HEADER = 0, MPEGTS_PESHEADER, MPEGTS_PESHEADER_FILL, MPEGTS_PAYLOAD, MPEGTS_SKIP, }; /* enough for PES header + length */ #define PES_START_SIZE 6 #define PES_HEADER_SIZE 9 #define MAX_PES_HEADER_SIZE (9 + 255) struct PESContext { int pid; int pcr_pid; /**< if -1 then all packets containing PCR are considered */ int stream_type; MpegTSContext *ts; AVFormatContext *stream; AVStream *st; enum MpegTSState state; /* used to get the format */ int data_index; int total_size; int pes_header_size; int64_t pts, dts; int64_t ts_packet_pos; /**< position of first TS packet of this PES packet */ uint8_t header[MAX_PES_HEADER_SIZE]; uint8_t *buffer; }; extern AVInputFormat mpegts_demuxer; static void clear_program(MpegTSContext *ts, unsigned int programid) { int i; for(i=0; inb_prg; i++) if(ts->prg[i].id == programid) ts->prg[i].nb_pids = 0; } static void clear_programs(MpegTSContext *ts) { av_freep(&ts->prg); ts->nb_prg=0; } static void add_pat_entry(MpegTSContext *ts, unsigned int programid) { struct Program *p; void *tmp = av_realloc(ts->prg, (ts->nb_prg+1)*sizeof(struct Program)); if(!tmp) return; ts->prg = tmp; p = &ts->prg[ts->nb_prg]; p->id = programid; p->nb_pids = 0; ts->nb_prg++; } static void add_pid_to_pmt(MpegTSContext *ts, unsigned int programid, unsigned int pid) { int i; struct Program *p = NULL; for(i=0; inb_prg; i++) { if(ts->prg[i].id == programid) { p = &ts->prg[i]; break; } } if(!p) return; if(p->nb_pids >= MAX_PIDS_PER_PROGRAM) return; p->pids[p->nb_pids++] = pid; } /** * \brief discard_pid() decides if the pid is to be discarded according * to caller's programs selection * \param ts : - TS context * \param pid : - pid * \return 1 if the pid is only comprised in programs that have .discard=AVDISCARD_ALL * 0 otherwise */ static int discard_pid(MpegTSContext *ts, unsigned int pid) { int i, j, k; int used = 0, discarded = 0; struct Program *p; for(i=0; inb_prg; i++) { p = &ts->prg[i]; for(j=0; jnb_pids; j++) { if(p->pids[j] != pid) continue; //is program with id p->id set to be discarded? for(k=0; kstream->nb_programs; k++) { if(ts->stream->programs[k]->id == p->id) { if(ts->stream->programs[k]->discard == AVDISCARD_ALL) discarded++; else used++; } } } } return !used && discarded; } /** * Assembles PES packets out of TS packets, and then calls the "section_cb" * function when they are complete. */ static void write_section_data(AVFormatContext *s, MpegTSFilter *tss1, const uint8_t *buf, int buf_size, int is_start) { MpegTSSectionFilter *tss = &tss1->u.section_filter; int len; if (is_start) { memcpy(tss->section_buf, buf, buf_size); tss->section_index = buf_size; tss->section_h_size = -1; tss->end_of_section_reached = 0; } else { if (tss->end_of_section_reached) return; len = 4096 - tss->section_index; if (buf_size < len) len = buf_size; memcpy(tss->section_buf + tss->section_index, buf, len); tss->section_index += len; } /* compute section length if possible */ if (tss->section_h_size == -1 && tss->section_index >= 3) { len = (AV_RB16(tss->section_buf + 1) & 0xfff) + 3; if (len > 4096) return; tss->section_h_size = len; } if (tss->section_h_size != -1 && tss->section_index >= tss->section_h_size) { tss->end_of_section_reached = 1; if (!tss->check_crc || av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, tss->section_buf, tss->section_h_size) == 0) tss->section_cb(tss1, tss->section_buf, tss->section_h_size); } } static MpegTSFilter *mpegts_open_section_filter(MpegTSContext *ts, unsigned int pid, SectionCallback *section_cb, void *opaque, int check_crc) { MpegTSFilter *filter; MpegTSSectionFilter *sec; dprintf(ts->stream, "Filter: pid=0x%x\n", pid); if (pid >= NB_PID_MAX || ts->pids[pid]) return NULL; filter = av_mallocz(sizeof(MpegTSFilter)); if (!filter) return NULL; ts->pids[pid] = filter; filter->type = MPEGTS_SECTION; filter->pid = pid; filter->last_cc = -1; sec = &filter->u.section_filter; sec->section_cb = section_cb; sec->opaque = opaque; sec->section_buf = av_malloc(MAX_SECTION_SIZE); sec->check_crc = check_crc; if (!sec->section_buf) { av_free(filter); return NULL; } return filter; } static MpegTSFilter *mpegts_open_pes_filter(MpegTSContext *ts, unsigned int pid, PESCallback *pes_cb, void *opaque) { MpegTSFilter *filter; MpegTSPESFilter *pes; if (pid >= NB_PID_MAX || ts->pids[pid]) return NULL; filter = av_mallocz(sizeof(MpegTSFilter)); if (!filter) return NULL; ts->pids[pid] = filter; filter->type = MPEGTS_PES; filter->pid = pid; filter->last_cc = -1; pes = &filter->u.pes_filter; pes->pes_cb = pes_cb; pes->opaque = opaque; return filter; } static void mpegts_close_filter(MpegTSContext *ts, MpegTSFilter *filter) { int pid; pid = filter->pid; if (filter->type == MPEGTS_SECTION) av_freep(&filter->u.section_filter.section_buf); else if (filter->type == MPEGTS_PES) { PESContext *pes = filter->u.pes_filter.opaque; av_freep(&pes->buffer); /* referenced private data will be freed later in * av_close_input_stream */ if (!((PESContext *)filter->u.pes_filter.opaque)->st) { av_freep(&filter->u.pes_filter.opaque); } } av_free(filter); ts->pids[pid] = NULL; } static int analyze(const uint8_t *buf, int size, int packet_size, int *index){ int stat[TS_MAX_PACKET_SIZE]; int i; int x=0; int best_score=0; memset(stat, 0, packet_size*sizeof(int)); for(x=i=0; i best_score){ best_score= stat[x]; if(index) *index= x; } } x++; if(x == packet_size) x= 0; } return best_score; } /* autodetect fec presence. Must have at least 1024 bytes */ static int get_packet_size(const uint8_t *buf, int size) { int score, fec_score, dvhs_score; if (size < (TS_FEC_PACKET_SIZE * 5 + 1)) return -1; score = analyze(buf, size, TS_PACKET_SIZE, NULL); dvhs_score = analyze(buf, size, TS_DVHS_PACKET_SIZE, NULL); fec_score= analyze(buf, size, TS_FEC_PACKET_SIZE, NULL); // av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score); if (score > fec_score && score > dvhs_score) return TS_PACKET_SIZE; else if(dvhs_score > score && dvhs_score > fec_score) return TS_DVHS_PACKET_SIZE; else if(score < fec_score && dvhs_score < fec_score) return TS_FEC_PACKET_SIZE; else return -1; } typedef struct SectionHeader { uint8_t tid; uint16_t id; uint8_t version; uint8_t sec_num; uint8_t last_sec_num; } SectionHeader; static inline int get8(const uint8_t **pp, const uint8_t *p_end) { const uint8_t *p; int c; p = *pp; if (p >= p_end) return -1; c = *p++; *pp = p; return c; } static inline int get16(const uint8_t **pp, const uint8_t *p_end) { const uint8_t *p; int c; p = *pp; if ((p + 1) >= p_end) return -1; c = AV_RB16(p); p += 2; *pp = p; return c; } /* read and allocate a DVB string preceeded by its length */ static char *getstr8(const uint8_t **pp, const uint8_t *p_end) { int len; const uint8_t *p; char *str; p = *pp; len = get8(&p, p_end); if (len < 0) return NULL; if ((p + len) > p_end) return NULL; str = av_malloc(len + 1); if (!str) return NULL; memcpy(str, p, len); str[len] = '\0'; p += len; *pp = p; return str; } static int parse_section_header(SectionHeader *h, const uint8_t **pp, const uint8_t *p_end) { int val; val = get8(pp, p_end); if (val < 0) return -1; h->tid = val; *pp += 2; val = get16(pp, p_end); if (val < 0) return -1; h->id = val; val = get8(pp, p_end); if (val < 0) return -1; h->version = (val >> 1) & 0x1f; val = get8(pp, p_end); if (val < 0) return -1; h->sec_num = val; val = get8(pp, p_end); if (val < 0) return -1; h->last_sec_num = val; return 0; } typedef struct { uint32_t stream_type; enum CodecType codec_type; enum CodecID codec_id; } StreamType; static const StreamType ISO_types[] = { { 0x01, CODEC_TYPE_VIDEO, CODEC_ID_MPEG2VIDEO }, { 0x02, CODEC_TYPE_VIDEO, CODEC_ID_MPEG2VIDEO }, { 0x03, CODEC_TYPE_AUDIO, CODEC_ID_MP3 }, { 0x04, CODEC_TYPE_AUDIO, CODEC_ID_MP3 }, { 0x0f, CODEC_TYPE_AUDIO, CODEC_ID_AAC }, { 0x10, CODEC_TYPE_VIDEO, CODEC_ID_MPEG4 }, { 0x1b, CODEC_TYPE_VIDEO, CODEC_ID_H264 }, { 0xd1, CODEC_TYPE_VIDEO, CODEC_ID_DIRAC }, { 0xea, CODEC_TYPE_VIDEO, CODEC_ID_VC1 }, { 0 }, }; static const StreamType HDMV_types[] = { { 0x81, CODEC_TYPE_AUDIO, CODEC_ID_AC3 }, { 0x82, CODEC_TYPE_AUDIO, CODEC_ID_DTS }, { 0x90, CODEC_TYPE_SUBTITLE, CODEC_ID_HDMV_PGS_SUBTITLE }, { 0 }, }; /* ATSC ? */ static const StreamType MISC_types[] = { { 0x81, CODEC_TYPE_AUDIO, CODEC_ID_AC3 }, { 0x8a, CODEC_TYPE_AUDIO, CODEC_ID_DTS }, { 0 }, }; static const StreamType REGD_types[] = { { MKTAG('d','r','a','c'), CODEC_TYPE_VIDEO, CODEC_ID_DIRAC }, { MKTAG('A','C','-','3'), CODEC_TYPE_AUDIO, CODEC_ID_AC3 }, { 0 }, }; /* descriptor present */ static const StreamType DESC_types[] = { { 0x6a, CODEC_TYPE_AUDIO, CODEC_ID_AC3 }, /* AC-3 descriptor */ { 0x7a, CODEC_TYPE_AUDIO, CODEC_ID_EAC3 }, /* E-AC-3 descriptor */ { 0x7b, CODEC_TYPE_AUDIO, CODEC_ID_DTS }, { 0x59, CODEC_TYPE_SUBTITLE, CODEC_ID_DVB_SUBTITLE }, /* subtitling descriptor */ { 0 }, }; static void mpegts_find_stream_type(AVStream *st, uint32_t stream_type, const StreamType *types) { for (; types->stream_type; types++) { if (stream_type == types->stream_type) { st->codec->codec_type = types->codec_type; st->codec->codec_id = types->codec_id; return; } } } static AVStream *new_pes_av_stream(PESContext *pes, uint32_t prog_reg_desc, uint32_t code) { AVStream *st = av_new_stream(pes->stream, pes->pid); if (!st) return NULL; av_set_pts_info(st, 33, 1, 90000); st->priv_data = pes; st->codec->codec_type = CODEC_TYPE_DATA; st->codec->codec_id = CODEC_ID_NONE; st->need_parsing = AVSTREAM_PARSE_FULL; pes->st = st; dprintf(pes->stream, "stream_type=%x pid=%x prog_reg_desc=%.4s\n", pes->stream_type, pes->pid, (char*)&prog_reg_desc); st->codec->codec_tag = pes->stream_type; mpegts_find_stream_type(st, pes->stream_type, ISO_types); if (prog_reg_desc == AV_RL32("HDMV") && st->codec->codec_id == CODEC_ID_NONE) mpegts_find_stream_type(st, pes->stream_type, HDMV_types); if (st->codec->codec_id == CODEC_ID_NONE) mpegts_find_stream_type(st, pes->stream_type, MISC_types); /* stream was not present in PMT, guess based on PES start code */ if (st->codec->codec_id == CODEC_ID_NONE) { if (code >= 0x1c0 && code <= 0x1df) { st->codec->codec_type = CODEC_TYPE_AUDIO; st->codec->codec_id = CODEC_ID_MP2; } else if (code == 0x1bd) { st->codec->codec_type = CODEC_TYPE_AUDIO; st->codec->codec_id = CODEC_ID_AC3; } } return st; } static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; SectionHeader h1, *h = &h1; PESContext *pes; AVStream *st; const uint8_t *p, *p_end, *desc_list_end, *desc_end; int program_info_length, pcr_pid, pid, stream_type; int desc_list_len, desc_len, desc_tag; int comp_page, anc_page; char language[4]; uint32_t prog_reg_desc = 0; /* registration descriptor */ #ifdef DEBUG dprintf(ts->stream, "PMT: len %i\n", section_len); av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len); #endif p_end = section + section_len - 4; p = section; if (parse_section_header(h, &p, p_end) < 0) return; dprintf(ts->stream, "sid=0x%x sec_num=%d/%d\n", h->id, h->sec_num, h->last_sec_num); if (h->tid != PMT_TID) return; clear_program(ts, h->id); pcr_pid = get16(&p, p_end) & 0x1fff; if (pcr_pid < 0) return; add_pid_to_pmt(ts, h->id, pcr_pid); dprintf(ts->stream, "pcr_pid=0x%x\n", pcr_pid); program_info_length = get16(&p, p_end) & 0xfff; if (program_info_length < 0) return; while(program_info_length >= 2) { uint8_t tag, len; tag = get8(&p, p_end); len = get8(&p, p_end); if(len > program_info_length - 2) //something else is broken, exit the program_descriptors_loop break; program_info_length -= len + 2; if(tag == 0x05 && len >= 4) { // registration descriptor prog_reg_desc = bytestream_get_le32(&p); len -= 4; } p += len; } p += program_info_length; if (p >= p_end) return; // stop parsing after pmt, we found header if (!ts->stream->nb_streams) ts->stop_parse = 1; for(;;) { st = 0; stream_type = get8(&p, p_end); if (stream_type < 0) break; pid = get16(&p, p_end) & 0x1fff; if (pid < 0) break; /* now create ffmpeg stream */ if (ts->pids[pid] && ts->pids[pid]->type == MPEGTS_PES) { pes = ts->pids[pid]->u.pes_filter.opaque; st = pes->st; } else { if (ts->pids[pid]) mpegts_close_filter(ts, ts->pids[pid]); //wrongly added sdt filter probably pes = add_pes_stream(ts, pid, pcr_pid, stream_type); if (pes) st = new_pes_av_stream(pes, prog_reg_desc, 0); } if (!st) return; add_pid_to_pmt(ts, h->id, pid); av_program_add_stream_index(ts->stream, h->id, st->index); desc_list_len = get16(&p, p_end) & 0xfff; if (desc_list_len < 0) break; desc_list_end = p + desc_list_len; if (desc_list_end > p_end) break; for(;;) { desc_tag = get8(&p, desc_list_end); if (desc_tag < 0) break; desc_len = get8(&p, desc_list_end); if (desc_len < 0) break; desc_end = p + desc_len; if (desc_end > desc_list_end) break; dprintf(ts->stream, "tag: 0x%02x len=%d\n", desc_tag, desc_len); if (st->codec->codec_id == CODEC_ID_NONE && stream_type == STREAM_TYPE_PRIVATE_DATA) mpegts_find_stream_type(st, desc_tag, DESC_types); switch(desc_tag) { case 0x59: /* subtitling descriptor */ language[0] = get8(&p, desc_end); language[1] = get8(&p, desc_end); language[2] = get8(&p, desc_end); language[3] = 0; get8(&p, desc_end); comp_page = get16(&p, desc_end); anc_page = get16(&p, desc_end); st->codec->sub_id = (anc_page << 16) | comp_page; av_metadata_set(&st->metadata, "language", language); break; case 0x0a: /* ISO 639 language descriptor */ language[0] = get8(&p, desc_end); language[1] = get8(&p, desc_end); language[2] = get8(&p, desc_end); language[3] = 0; av_metadata_set(&st->metadata, "language", language); break; case 0x05: /* registration descriptor */ st->codec->codec_tag = bytestream_get_le32(&p); dprintf(ts->stream, "reg_desc=%.4s\n", (char*)&st->codec->codec_tag); if (st->codec->codec_id == CODEC_ID_NONE && stream_type == STREAM_TYPE_PRIVATE_DATA) mpegts_find_stream_type(st, st->codec->codec_tag, REGD_types); break; default: break; } p = desc_end; } p = desc_list_end; } /* all parameters are there */ mpegts_close_filter(ts, filter); } static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; SectionHeader h1, *h = &h1; const uint8_t *p, *p_end; int sid, pmt_pid; #ifdef DEBUG dprintf(ts->stream, "PAT:\n"); av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len); #endif p_end = section + section_len - 4; p = section; if (parse_section_header(h, &p, p_end) < 0) return; if (h->tid != PAT_TID) return; clear_programs(ts); for(;;) { sid = get16(&p, p_end); if (sid < 0) break; pmt_pid = get16(&p, p_end) & 0x1fff; if (pmt_pid < 0) break; dprintf(ts->stream, "sid=0x%x pid=0x%x\n", sid, pmt_pid); if (sid == 0x0000) { /* NIT info */ } else { av_new_program(ts->stream, sid); mpegts_open_section_filter(ts, pmt_pid, pmt_cb, ts, 1); add_pat_entry(ts, sid); add_pid_to_pmt(ts, sid, 0); //add pat pid to program add_pid_to_pmt(ts, sid, pmt_pid); } } } static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; SectionHeader h1, *h = &h1; const uint8_t *p, *p_end, *desc_list_end, *desc_end; int onid, val, sid, desc_list_len, desc_tag, desc_len, service_type; char *name, *provider_name; #ifdef DEBUG dprintf(ts->stream, "SDT:\n"); av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len); #endif p_end = section + section_len - 4; p = section; if (parse_section_header(h, &p, p_end) < 0) return; if (h->tid != SDT_TID) return; onid = get16(&p, p_end); if (onid < 0) return; val = get8(&p, p_end); if (val < 0) return; for(;;) { sid = get16(&p, p_end); if (sid < 0) break; val = get8(&p, p_end); if (val < 0) break; desc_list_len = get16(&p, p_end) & 0xfff; if (desc_list_len < 0) break; desc_list_end = p + desc_list_len; if (desc_list_end > p_end) break; for(;;) { desc_tag = get8(&p, desc_list_end); if (desc_tag < 0) break; desc_len = get8(&p, desc_list_end); desc_end = p + desc_len; if (desc_end > desc_list_end) break; dprintf(ts->stream, "tag: 0x%02x len=%d\n", desc_tag, desc_len); switch(desc_tag) { case 0x48: service_type = get8(&p, p_end); if (service_type < 0) break; provider_name = getstr8(&p, p_end); if (!provider_name) break; name = getstr8(&p, p_end); if (name) { AVProgram *program = av_new_program(ts->stream, sid); if(program) { av_metadata_set(&program->metadata, "name", name); av_metadata_set(&program->metadata, "provider_name", provider_name); } } av_free(name); av_free(provider_name); break; default: break; } p = desc_end; } p = desc_list_end; } } static int64_t get_pts(const uint8_t *p) { int64_t pts = (int64_t)((p[0] >> 1) & 0x07) << 30; pts |= (AV_RB16(p + 1) >> 1) << 15; pts |= AV_RB16(p + 3) >> 1; return pts; } static void new_pes_packet(PESContext *pes, AVPacket *pkt) { av_init_packet(pkt); pkt->destruct = av_destruct_packet; pkt->data = pes->buffer; pkt->size = pes->data_index; memset(pkt->data+pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE); pkt->stream_index = pes->st->index; pkt->pts = pes->pts; pkt->dts = pes->dts; /* store position of first TS packet of this PES packet */ pkt->pos = pes->ts_packet_pos; /* reset pts values */ pes->pts = AV_NOPTS_VALUE; pes->dts = AV_NOPTS_VALUE; pes->buffer = NULL; pes->data_index = 0; } /* return non zero if a packet could be constructed */ static int mpegts_push_data(MpegTSFilter *filter, const uint8_t *buf, int buf_size, int is_start, int64_t pos) { PESContext *pes = filter->u.pes_filter.opaque; MpegTSContext *ts = pes->ts; const uint8_t *p; int len, code; if(!ts->pkt) return 0; if (is_start) { if (pes->state == MPEGTS_PAYLOAD && pes->data_index > 0) { new_pes_packet(pes, ts->pkt); ts->stop_parse = 1; } pes->state = MPEGTS_HEADER; pes->data_index = 0; pes->ts_packet_pos = pos; } p = buf; while (buf_size > 0) { switch(pes->state) { case MPEGTS_HEADER: len = PES_START_SIZE - pes->data_index; if (len > buf_size) len = buf_size; memcpy(pes->header + pes->data_index, p, len); pes->data_index += len; p += len; buf_size -= len; if (pes->data_index == PES_START_SIZE) { /* we got all the PES or section header. We can now decide */ #if 0 av_hex_dump_log(pes->stream, AV_LOG_DEBUG, pes->header, pes->data_index); #endif if (pes->header[0] == 0x00 && pes->header[1] == 0x00 && pes->header[2] == 0x01) { /* it must be an mpeg2 PES stream */ code = pes->header[3] | 0x100; dprintf(pes->stream, "pid=%x pes_code=%#x\n", pes->pid, code); if ((!pes->st && pes->stream->nb_streams == MAX_STREAMS) || (pes->st && pes->st->discard == AVDISCARD_ALL) || code == 0x1be) /* padding_stream */ goto skip; /* stream not present in PMT */ if (!pes->st) pes->st = new_pes_av_stream(pes, 0, code); if (!pes->st) return AVERROR(ENOMEM); pes->total_size = AV_RB16(pes->header + 4); /* NOTE: a zero total size means the PES size is unbounded */ if (!pes->total_size) pes->total_size = MAX_PES_PAYLOAD; /* allocate pes buffer */ pes->buffer = av_malloc(pes->total_size+FF_INPUT_BUFFER_PADDING_SIZE); if (!pes->buffer) return AVERROR(ENOMEM); if (code != 0x1bc && code != 0x1bf && /* program_stream_map, private_stream_2 */ code != 0x1f0 && code != 0x1f1 && /* ECM, EMM */ code != 0x1ff && code != 0x1f2 && /* program_stream_directory, DSMCC_stream */ code != 0x1f8) { /* ITU-T Rec. H.222.1 type E stream */ pes->state = MPEGTS_PESHEADER; if (pes->st->codec->codec_id == CODEC_ID_NONE) { dprintf(pes->stream, "pid=%x stream_type=%x probing\n", pes->pid, pes->stream_type); pes->st->codec->codec_id = CODEC_ID_PROBE; } } else { pes->state = MPEGTS_PAYLOAD; pes->data_index = 0; } } else { /* otherwise, it should be a table */ /* skip packet */ skip: pes->state = MPEGTS_SKIP; continue; } } break; /**********************************************/ /* PES packing parsing */ case MPEGTS_PESHEADER: len = PES_HEADER_SIZE - pes->data_index; if (len < 0) return -1; if (len > buf_size) len = buf_size; memcpy(pes->header + pes->data_index, p, len); pes->data_index += len; p += len; buf_size -= len; if (pes->data_index == PES_HEADER_SIZE) { pes->pes_header_size = pes->header[8] + 9; pes->state = MPEGTS_PESHEADER_FILL; } break; case MPEGTS_PESHEADER_FILL: len = pes->pes_header_size - pes->data_index; if (len < 0) return -1; if (len > buf_size) len = buf_size; memcpy(pes->header + pes->data_index, p, len); pes->data_index += len; p += len; buf_size -= len; if (pes->data_index == pes->pes_header_size) { const uint8_t *r; unsigned int flags; flags = pes->header[7]; r = pes->header + 9; pes->pts = AV_NOPTS_VALUE; pes->dts = AV_NOPTS_VALUE; if ((flags & 0xc0) == 0x80) { pes->dts = pes->pts = get_pts(r); r += 5; } else if ((flags & 0xc0) == 0xc0) { pes->pts = get_pts(r); r += 5; pes->dts = get_pts(r); r += 5; } /* we got the full header. We parse it and get the payload */ pes->state = MPEGTS_PAYLOAD; pes->data_index = 0; } break; case MPEGTS_PAYLOAD: if (buf_size > 0) { if (pes->data_index+buf_size > pes->total_size) { new_pes_packet(pes, ts->pkt); pes->total_size = MAX_PES_PAYLOAD; pes->buffer = av_malloc(pes->total_size+FF_INPUT_BUFFER_PADDING_SIZE); if (!pes->buffer) return AVERROR(ENOMEM); ts->stop_parse = 1; } memcpy(pes->buffer+pes->data_index, p, buf_size); pes->data_index += buf_size; } buf_size = 0; break; case MPEGTS_SKIP: buf_size = 0; break; } } return 0; } static PESContext *add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type) { MpegTSFilter *tss; PESContext *pes; /* if no pid found, then add a pid context */ pes = av_mallocz(sizeof(PESContext)); if (!pes) return 0; pes->ts = ts; pes->stream = ts->stream; pes->pid = pid; pes->pcr_pid = pcr_pid; pes->stream_type = stream_type; pes->state = MPEGTS_SKIP; pes->pts = AV_NOPTS_VALUE; pes->dts = AV_NOPTS_VALUE; tss = mpegts_open_pes_filter(ts, pid, mpegts_push_data, pes); if (!tss) { av_free(pes); return 0; } return pes; } /* handle one TS packet */ static int handle_packet(MpegTSContext *ts, const uint8_t *packet) { AVFormatContext *s = ts->stream; MpegTSFilter *tss; int len, pid, cc, cc_ok, afc, is_start; const uint8_t *p, *p_end; int64_t pos; pid = AV_RB16(packet + 1) & 0x1fff; if(pid && discard_pid(ts, pid)) return 0; is_start = packet[1] & 0x40; tss = ts->pids[pid]; if (ts->auto_guess && tss == NULL && is_start) { add_pes_stream(ts, pid, -1, 0); tss = ts->pids[pid]; } if (!tss) return 0; /* continuity check (currently not used) */ cc = (packet[3] & 0xf); cc_ok = (tss->last_cc < 0) || ((((tss->last_cc + 1) & 0x0f) == cc)); tss->last_cc = cc; /* skip adaptation field */ afc = (packet[3] >> 4) & 3; p = packet + 4; if (afc == 0) /* reserved value */ return 0; if (afc == 2) /* adaptation field only */ return 0; if (afc == 3) { /* skip adapation field */ p += p[0] + 1; } /* if past the end of packet, ignore */ p_end = packet + TS_PACKET_SIZE; if (p >= p_end) return 0; pos = url_ftell(ts->stream->pb); ts->pos47= pos % ts->raw_packet_size; if (tss->type == MPEGTS_SECTION) { if (is_start) { /* pointer field present */ len = *p++; if (p + len > p_end) return 0; if (len && cc_ok) { /* write remaining section bytes */ write_section_data(s, tss, p, len, 0); /* check whether filter has been closed */ if (!ts->pids[pid]) return 0; } p += len; if (p < p_end) { write_section_data(s, tss, p, p_end - p, 1); } } else { if (cc_ok) { write_section_data(s, tss, p, p_end - p, 0); } } } else { int ret; // Note: The position here points actually behind the current packet. if ((ret = tss->u.pes_filter.pes_cb(tss, p, p_end - p, is_start, pos - ts->raw_packet_size)) < 0) return ret; } return 0; } /* XXX: try to find a better synchro over several packets (use get_packet_size() ?) */ static int mpegts_resync(ByteIOContext *pb) { int c, i; for(i = 0;i < MAX_RESYNC_SIZE; i++) { c = url_fgetc(pb); if (c < 0) return -1; if (c == 0x47) { url_fseek(pb, -1, SEEK_CUR); return 0; } } /* no sync found */ return -1; } /* return -1 if error or EOF. Return 0 if OK. */ static int read_packet(ByteIOContext *pb, uint8_t *buf, int raw_packet_size) { int skip, len; for(;;) { len = get_buffer(pb, buf, TS_PACKET_SIZE); if (len != TS_PACKET_SIZE) return AVERROR(EIO); /* check paquet sync byte */ if (buf[0] != 0x47) { /* find a new packet start */ url_fseek(pb, -TS_PACKET_SIZE, SEEK_CUR); if (mpegts_resync(pb) < 0) return AVERROR_INVALIDDATA; else continue; } else { skip = raw_packet_size - TS_PACKET_SIZE; if (skip > 0) url_fskip(pb, skip); break; } } return 0; } static int handle_packets(MpegTSContext *ts, int nb_packets) { AVFormatContext *s = ts->stream; ByteIOContext *pb = s->pb; uint8_t packet[TS_PACKET_SIZE]; int packet_num, ret; ts->stop_parse = 0; packet_num = 0; for(;;) { if (ts->stop_parse>0) break; packet_num++; if (nb_packets != 0 && packet_num >= nb_packets) break; ret = read_packet(pb, packet, ts->raw_packet_size); if (ret != 0) return ret; ret = handle_packet(ts, packet); if (ret != 0) return ret; } return 0; } static int mpegts_probe(AVProbeData *p) { #if 1 const int size= p->buf_size; int score, fec_score, dvhs_score; int check_count= size / TS_FEC_PACKET_SIZE; #define CHECK_COUNT 10 if (check_count < CHECK_COUNT) return -1; score = analyze(p->buf, TS_PACKET_SIZE *check_count, TS_PACKET_SIZE , NULL)*CHECK_COUNT/check_count; dvhs_score= analyze(p->buf, TS_DVHS_PACKET_SIZE*check_count, TS_DVHS_PACKET_SIZE, NULL)*CHECK_COUNT/check_count; fec_score = analyze(p->buf, TS_FEC_PACKET_SIZE *check_count, TS_FEC_PACKET_SIZE , NULL)*CHECK_COUNT/check_count; // av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score); // we need a clear definition for the returned score otherwise things will become messy sooner or later if (score > fec_score && score > dvhs_score && score > 6) return AVPROBE_SCORE_MAX + score - CHECK_COUNT; else if(dvhs_score > score && dvhs_score > fec_score && dvhs_score > 6) return AVPROBE_SCORE_MAX + dvhs_score - CHECK_COUNT; else if( fec_score > 6) return AVPROBE_SCORE_MAX + fec_score - CHECK_COUNT; else return -1; #else /* only use the extension for safer guess */ if (match_ext(p->filename, "ts")) return AVPROBE_SCORE_MAX; else return 0; #endif } /* return the 90kHz PCR and the extension for the 27MHz PCR. return (-1) if not available */ static int parse_pcr(int64_t *ppcr_high, int *ppcr_low, const uint8_t *packet) { int afc, len, flags; const uint8_t *p; unsigned int v; afc = (packet[3] >> 4) & 3; if (afc <= 1) return -1; p = packet + 4; len = p[0]; p++; if (len == 0) return -1; flags = *p++; len--; if (!(flags & 0x10)) return -1; if (len < 6) return -1; v = AV_RB32(p); *ppcr_high = ((int64_t)v << 1) | (p[4] >> 7); *ppcr_low = ((p[4] & 1) << 8) | p[5]; return 0; } static int mpegts_read_header(AVFormatContext *s, AVFormatParameters *ap) { MpegTSContext *ts = s->priv_data; ByteIOContext *pb = s->pb; uint8_t buf[5*1024]; int len; int64_t pos; if (ap) { ts->mpeg2ts_compute_pcr = ap->mpeg2ts_compute_pcr; if(ap->mpeg2ts_raw){ av_log(s, AV_LOG_ERROR, "use mpegtsraw_demuxer!\n"); return -1; } } /* read the first 1024 bytes to get packet size */ pos = url_ftell(pb); len = get_buffer(pb, buf, sizeof(buf)); if (len != sizeof(buf)) goto fail; ts->raw_packet_size = get_packet_size(buf, sizeof(buf)); if (ts->raw_packet_size <= 0) goto fail; ts->stream = s; ts->auto_guess = 0; if (s->iformat == &mpegts_demuxer) { /* normal demux */ /* first do a scaning to get all the services */ url_fseek(pb, pos, SEEK_SET); mpegts_open_section_filter(ts, SDT_PID, sdt_cb, ts, 1); mpegts_open_section_filter(ts, PAT_PID, pat_cb, ts, 1); handle_packets(ts, s->probesize); /* if could not find service, enable auto_guess */ ts->auto_guess = 1; dprintf(ts->stream, "tuning done\n"); s->ctx_flags |= AVFMTCTX_NOHEADER; } else { AVStream *st; int pcr_pid, pid, nb_packets, nb_pcrs, ret, pcr_l; int64_t pcrs[2], pcr_h; int packet_count[2]; uint8_t packet[TS_PACKET_SIZE]; /* only read packets */ st = av_new_stream(s, 0); if (!st) goto fail; av_set_pts_info(st, 60, 1, 27000000); st->codec->codec_type = CODEC_TYPE_DATA; st->codec->codec_id = CODEC_ID_MPEG2TS; /* we iterate until we find two PCRs to estimate the bitrate */ pcr_pid = -1; nb_pcrs = 0; nb_packets = 0; for(;;) { ret = read_packet(s->pb, packet, ts->raw_packet_size); if (ret < 0) return -1; pid = AV_RB16(packet + 1) & 0x1fff; if ((pcr_pid == -1 || pcr_pid == pid) && parse_pcr(&pcr_h, &pcr_l, packet) == 0) { pcr_pid = pid; packet_count[nb_pcrs] = nb_packets; pcrs[nb_pcrs] = pcr_h * 300 + pcr_l; nb_pcrs++; if (nb_pcrs >= 2) break; } nb_packets++; } /* NOTE1: the bitrate is computed without the FEC */ /* NOTE2: it is only the bitrate of the start of the stream */ ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] - packet_count[0]); ts->cur_pcr = pcrs[0] - ts->pcr_incr * packet_count[0]; s->bit_rate = (TS_PACKET_SIZE * 8) * 27e6 / ts->pcr_incr; st->codec->bit_rate = s->bit_rate; st->start_time = ts->cur_pcr; #if 0 av_log(ts->stream, AV_LOG_DEBUG, "start=%0.3f pcr=%0.3f incr=%d\n", st->start_time / 1000000.0, pcrs[0] / 27e6, ts->pcr_incr); #endif } url_fseek(pb, pos, SEEK_SET); return 0; fail: return -1; } #define MAX_PACKET_READAHEAD ((128 * 1024) / 188) static int mpegts_raw_read_packet(AVFormatContext *s, AVPacket *pkt) { MpegTSContext *ts = s->priv_data; int ret, i; int64_t pcr_h, next_pcr_h, pos; int pcr_l, next_pcr_l; uint8_t pcr_buf[12]; if (av_new_packet(pkt, TS_PACKET_SIZE) < 0) return AVERROR(ENOMEM); pkt->pos= url_ftell(s->pb); ret = read_packet(s->pb, pkt->data, ts->raw_packet_size); if (ret < 0) { av_free_packet(pkt); return ret; } if (ts->mpeg2ts_compute_pcr) { /* compute exact PCR for each packet */ if (parse_pcr(&pcr_h, &pcr_l, pkt->data) == 0) { /* we read the next PCR (XXX: optimize it by using a bigger buffer */ pos = url_ftell(s->pb); for(i = 0; i < MAX_PACKET_READAHEAD; i++) { url_fseek(s->pb, pos + i * ts->raw_packet_size, SEEK_SET); get_buffer(s->pb, pcr_buf, 12); if (parse_pcr(&next_pcr_h, &next_pcr_l, pcr_buf) == 0) { /* XXX: not precise enough */ ts->pcr_incr = ((next_pcr_h - pcr_h) * 300 + (next_pcr_l - pcr_l)) / (i + 1); break; } } url_fseek(s->pb, pos, SEEK_SET); /* no next PCR found: we use previous increment */ ts->cur_pcr = pcr_h * 300 + pcr_l; } pkt->pts = ts->cur_pcr; pkt->duration = ts->pcr_incr; ts->cur_pcr += ts->pcr_incr; } pkt->stream_index = 0; return 0; } static int mpegts_read_packet(AVFormatContext *s, AVPacket *pkt) { MpegTSContext *ts = s->priv_data; int ret, i; if (url_ftell(s->pb) != ts->last_pos) { /* seek detected, flush pes buffer */ for (i = 0; i < NB_PID_MAX; i++) { if (ts->pids[i] && ts->pids[i]->type == MPEGTS_PES) { PESContext *pes = ts->pids[i]->u.pes_filter.opaque; av_freep(&pes->buffer); pes->data_index = 0; pes->state = MPEGTS_SKIP; /* skip until pes header */ } } } ts->pkt = pkt; ret = handle_packets(ts, 0); if (ret < 0) { /* flush pes data left */ for (i = 0; i < NB_PID_MAX; i++) { if (ts->pids[i] && ts->pids[i]->type == MPEGTS_PES) { PESContext *pes = ts->pids[i]->u.pes_filter.opaque; if (pes->state == MPEGTS_PAYLOAD && pes->data_index > 0) { new_pes_packet(pes, pkt); ret = 0; break; } } } } ts->last_pos = url_ftell(s->pb); return ret; } static int mpegts_read_close(AVFormatContext *s) { MpegTSContext *ts = s->priv_data; int i; clear_programs(ts); for(i=0;ipids[i]) mpegts_close_filter(ts, ts->pids[i]); return 0; } static int64_t mpegts_get_pcr(AVFormatContext *s, int stream_index, int64_t *ppos, int64_t pos_limit) { MpegTSContext *ts = s->priv_data; int64_t pos, timestamp; uint8_t buf[TS_PACKET_SIZE]; int pcr_l, pcr_pid = ((PESContext*)s->streams[stream_index]->priv_data)->pcr_pid; const int find_next= 1; pos = ((*ppos + ts->raw_packet_size - 1 - ts->pos47) / ts->raw_packet_size) * ts->raw_packet_size + ts->pos47; if (find_next) { for(;;) { url_fseek(s->pb, pos, SEEK_SET); if (get_buffer(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE) return AV_NOPTS_VALUE; if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) && parse_pcr(×tamp, &pcr_l, buf) == 0) { break; } pos += ts->raw_packet_size; } } else { for(;;) { pos -= ts->raw_packet_size; if (pos < 0) return AV_NOPTS_VALUE; url_fseek(s->pb, pos, SEEK_SET); if (get_buffer(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE) return AV_NOPTS_VALUE; if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) && parse_pcr(×tamp, &pcr_l, buf) == 0) { break; } } } *ppos = pos; return timestamp; } static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags); static int read_seek2(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t target_ts, int64_t max_ts, int flags) { int64_t pos; int64_t ts_ret, ts_adj; int stream_index_gen_search; AVStream *st; AVParserState *backup; backup = ff_store_parser_state(s); // detect direction of seeking for search purposes flags |= (target_ts - min_ts > (uint64_t)(max_ts - target_ts)) ? AVSEEK_FLAG_BACKWARD : 0; if (flags & AVSEEK_FLAG_BYTE) { /* use position directly, we will search starting from it */ pos = target_ts; } else { /* search for some position with good timestamp match */ if(stream_index < 0){ stream_index_gen_search = av_find_default_stream_index(s); if (stream_index_gen_search < 0) { ff_restore_parser_state(s, backup); return -1; } st = s->streams[stream_index_gen_search]; /* timestamp for default must be expressed in AV_TIME_BASE units */ ts_adj = av_rescale(target_ts, st->time_base.den, AV_TIME_BASE * (int64_t)st->time_base.num); } else { ts_adj = target_ts; stream_index_gen_search = stream_index; } pos = av_gen_search(s, stream_index_gen_search, ts_adj, 0, INT64_MAX, -1, AV_NOPTS_VALUE, AV_NOPTS_VALUE, flags, &ts_ret, mpegts_get_pcr); if (pos < 0) { ff_restore_parser_state(s, backup); return -1; } } /* search for actual matching keyframe/starting position for all streams */ if (ff_gen_syncpoint_search(s, stream_index, pos, min_ts, target_ts, max_ts, flags) < 0) { ff_restore_parser_state(s, backup); return -1; } ff_free_parser_state(s, backup); return 0; } static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags) { int ret; if (flags & AVSEEK_FLAG_BACKWARD) { ret = read_seek2(s, stream_index, INT64_MIN, target_ts, target_ts, flags & ~AVSEEK_FLAG_BACKWARD); if (ret < 0) { // for compatibility reasons, seek to best-fitting timestamp ret = read_seek2(s, stream_index, INT64_MIN, target_ts, INT64_MAX, flags & ~AVSEEK_FLAG_BACKWARD); } } else { ret = read_seek2(s, stream_index, target_ts, target_ts, INT64_MAX, flags); if (ret < 0) { // for compatibility reasons, seek to best-fitting timestamp ret = read_seek2(s, stream_index, INT64_MIN, target_ts, INT64_MAX, flags); } } return ret; } /**************************************************************/ /* parsing functions - called from other demuxers such as RTP */ MpegTSContext *mpegts_parse_open(AVFormatContext *s) { MpegTSContext *ts; ts = av_mallocz(sizeof(MpegTSContext)); if (!ts) return NULL; /* no stream case, currently used by RTP */ ts->raw_packet_size = TS_PACKET_SIZE; ts->stream = s; ts->auto_guess = 1; return ts; } /* return the consumed length if a packet was output, or -1 if no packet is output */ int mpegts_parse_packet(MpegTSContext *ts, AVPacket *pkt, const uint8_t *buf, int len) { int len1; len1 = len; ts->pkt = pkt; ts->stop_parse = 0; for(;;) { if (ts->stop_parse>0) break; if (len < TS_PACKET_SIZE) return -1; if (buf[0] != 0x47) { buf++; len--; } else { handle_packet(ts, buf); buf += TS_PACKET_SIZE; len -= TS_PACKET_SIZE; } } return len1 - len; } void mpegts_parse_close(MpegTSContext *ts) { int i; for(i=0;ipids[i]); av_free(ts); } AVInputFormat mpegts_demuxer = { "mpegts", NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"), sizeof(MpegTSContext), mpegts_probe, mpegts_read_header, mpegts_read_packet, mpegts_read_close, read_seek, mpegts_get_pcr, .flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT, .read_seek2 = read_seek2, }; AVInputFormat mpegtsraw_demuxer = { "mpegtsraw", NULL_IF_CONFIG_SMALL("MPEG-2 raw transport stream format"), sizeof(MpegTSContext), NULL, mpegts_read_header, mpegts_raw_read_packet, mpegts_read_close, read_seek, mpegts_get_pcr, .flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT, .read_seek2 = read_seek2, };