| /* |
| * MPEG1/2 demuxer |
| * Copyright (c) 2000, 2001, 2002 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 "avformat.h" |
| #include "mpeg.h" |
| |
| //#define DEBUG_SEEK |
| |
| #undef NDEBUG |
| #include <assert.h> |
| |
| /*********************************************/ |
| /* demux code */ |
| |
| #define MAX_SYNC_SIZE 100000 |
| |
| static int check_pes(uint8_t *p, uint8_t *end){ |
| int pes1; |
| int pes2= (p[3] & 0xC0) == 0x80 |
| && (p[4] & 0xC0) != 0x40 |
| &&((p[4] & 0xC0) == 0x00 || (p[4]&0xC0)>>2 == (p[6]&0xF0)); |
| |
| for(p+=3; p<end && *p == 0xFF; p++); |
| if((*p&0xC0) == 0x40) p+=2; |
| if((*p&0xF0) == 0x20){ |
| pes1= p[0]&p[2]&p[4]&1; |
| p+=5; |
| }else if((*p&0xF0) == 0x30){ |
| pes1= p[0]&p[2]&p[4]&p[5]&p[7]&p[9]&1; |
| p+=10; |
| }else |
| pes1 = *p == 0x0F; |
| |
| return pes1||pes2; |
| } |
| |
| static int mpegps_probe(AVProbeData *p) |
| { |
| uint32_t code= -1; |
| int sys=0, pspack=0, priv1=0, vid=0, audio=0, invalid=0; |
| int i; |
| int score=0; |
| |
| for(i=0; i<p->buf_size; i++){ |
| code = (code<<8) + p->buf[i]; |
| if ((code & 0xffffff00) == 0x100) { |
| int pes= check_pes(p->buf+i, p->buf+p->buf_size); |
| |
| if(code == SYSTEM_HEADER_START_CODE) sys++; |
| else if(code == PRIVATE_STREAM_1) priv1++; |
| else if(code == PACK_START_CODE) pspack++; |
| else if((code & 0xf0) == VIDEO_ID && pes) vid++; |
| else if((code & 0xe0) == AUDIO_ID && pes) audio++; |
| |
| else if((code & 0xf0) == VIDEO_ID && !pes) invalid++; |
| else if((code & 0xe0) == AUDIO_ID && !pes) invalid++; |
| } |
| } |
| |
| if(vid+audio > invalid) /* invalid VDR files nd short PES streams */ |
| score= AVPROBE_SCORE_MAX/4; |
| |
| //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d %d len:%d\n", sys, priv1, pspack,vid, audio, p->buf_size); |
| if(sys>invalid && sys*9 <= pspack*10) |
| return AVPROBE_SCORE_MAX/2+2; // +1 for .mpg |
| if(priv1 + vid + audio > invalid && (priv1+vid+audio)*9 <= pspack*10) |
| return AVPROBE_SCORE_MAX/2+2; // +1 for .mpg |
| if((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys && !pspack && p->buf_size>2048) /* PES stream */ |
| return AVPROBE_SCORE_MAX/2+2; |
| |
| //02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1 |
| return score; |
| } |
| |
| |
| typedef struct MpegDemuxContext { |
| int32_t header_state; |
| unsigned char psm_es_type[256]; |
| int sofdec; |
| } MpegDemuxContext; |
| |
| static int mpegps_read_header(AVFormatContext *s, |
| AVFormatParameters *ap) |
| { |
| MpegDemuxContext *m = s->priv_data; |
| const char *sofdec = "Sofdec"; |
| int v, i = 0; |
| |
| m->header_state = 0xff; |
| s->ctx_flags |= AVFMTCTX_NOHEADER; |
| |
| m->sofdec = -1; |
| do { |
| v = get_byte(s->pb); |
| m->header_state = m->header_state << 8 | v; |
| m->sofdec++; |
| } while (v == sofdec[i] && i++ < 6); |
| |
| /* no need to do more */ |
| return 0; |
| } |
| |
| static int64_t get_pts(ByteIOContext *pb, int c) |
| { |
| uint8_t buf[5]; |
| |
| buf[0] = c<0 ? get_byte(pb) : c; |
| get_buffer(pb, buf+1, 4); |
| |
| return ff_parse_pes_pts(buf); |
| } |
| |
| static int find_next_start_code(ByteIOContext *pb, int *size_ptr, |
| int32_t *header_state) |
| { |
| unsigned int state, v; |
| int val, n; |
| |
| state = *header_state; |
| n = *size_ptr; |
| while (n > 0) { |
| if (url_feof(pb)) |
| break; |
| v = get_byte(pb); |
| n--; |
| if (state == 0x000001) { |
| state = ((state << 8) | v) & 0xffffff; |
| val = state; |
| goto found; |
| } |
| state = ((state << 8) | v) & 0xffffff; |
| } |
| val = -1; |
| found: |
| *header_state = state; |
| *size_ptr = n; |
| return val; |
| } |
| |
| #if 0 /* unused, remove? */ |
| /* XXX: optimize */ |
| static int find_prev_start_code(ByteIOContext *pb, int *size_ptr) |
| { |
| int64_t pos, pos_start; |
| int max_size, start_code; |
| |
| max_size = *size_ptr; |
| pos_start = url_ftell(pb); |
| |
| /* in order to go faster, we fill the buffer */ |
| pos = pos_start - 16386; |
| if (pos < 0) |
| pos = 0; |
| url_fseek(pb, pos, SEEK_SET); |
| get_byte(pb); |
| |
| pos = pos_start; |
| for(;;) { |
| pos--; |
| if (pos < 0 || (pos_start - pos) >= max_size) { |
| start_code = -1; |
| goto the_end; |
| } |
| url_fseek(pb, pos, SEEK_SET); |
| start_code = get_be32(pb); |
| if ((start_code & 0xffffff00) == 0x100) |
| break; |
| } |
| the_end: |
| *size_ptr = pos_start - pos; |
| return start_code; |
| } |
| #endif |
| |
| /** |
| * Extracts stream types from a program stream map |
| * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35 |
| * |
| * @return number of bytes occupied by PSM in the bitstream |
| */ |
| static long mpegps_psm_parse(MpegDemuxContext *m, ByteIOContext *pb) |
| { |
| int psm_length, ps_info_length, es_map_length; |
| |
| psm_length = get_be16(pb); |
| get_byte(pb); |
| get_byte(pb); |
| ps_info_length = get_be16(pb); |
| |
| /* skip program_stream_info */ |
| url_fskip(pb, ps_info_length); |
| es_map_length = get_be16(pb); |
| |
| /* at least one es available? */ |
| while (es_map_length >= 4){ |
| unsigned char type = get_byte(pb); |
| unsigned char es_id = get_byte(pb); |
| uint16_t es_info_length = get_be16(pb); |
| /* remember mapping from stream id to stream type */ |
| m->psm_es_type[es_id] = type; |
| /* skip program_stream_info */ |
| url_fskip(pb, es_info_length); |
| es_map_length -= 4 + es_info_length; |
| } |
| get_be32(pb); /* crc32 */ |
| return 2 + psm_length; |
| } |
| |
| /* read the next PES header. Return its position in ppos |
| (if not NULL), and its start code, pts and dts. |
| */ |
| static int mpegps_read_pes_header(AVFormatContext *s, |
| int64_t *ppos, int *pstart_code, |
| int64_t *ppts, int64_t *pdts) |
| { |
| MpegDemuxContext *m = s->priv_data; |
| int len, size, startcode, c, flags, header_len; |
| int pes_ext, ext2_len, id_ext, skip; |
| int64_t pts, dts; |
| int64_t last_sync= url_ftell(s->pb); |
| |
| error_redo: |
| url_fseek(s->pb, last_sync, SEEK_SET); |
| redo: |
| /* next start code (should be immediately after) */ |
| m->header_state = 0xff; |
| size = MAX_SYNC_SIZE; |
| startcode = find_next_start_code(s->pb, &size, &m->header_state); |
| last_sync = url_ftell(s->pb); |
| //printf("startcode=%x pos=0x%"PRIx64"\n", startcode, url_ftell(s->pb)); |
| if (startcode < 0) |
| return AVERROR(EIO); |
| if (startcode == PACK_START_CODE) |
| goto redo; |
| if (startcode == SYSTEM_HEADER_START_CODE) |
| goto redo; |
| if (startcode == PADDING_STREAM) { |
| url_fskip(s->pb, get_be16(s->pb)); |
| goto redo; |
| } |
| if (startcode == PRIVATE_STREAM_2) { |
| len = get_be16(s->pb); |
| if (!m->sofdec) { |
| while (len-- >= 6) { |
| if (get_byte(s->pb) == 'S') { |
| uint8_t buf[5]; |
| get_buffer(s->pb, buf, sizeof(buf)); |
| m->sofdec = !memcmp(buf, "ofdec", 5); |
| len -= sizeof(buf); |
| break; |
| } |
| } |
| m->sofdec -= !m->sofdec; |
| } |
| url_fskip(s->pb, len); |
| goto redo; |
| } |
| if (startcode == PROGRAM_STREAM_MAP) { |
| mpegps_psm_parse(m, s->pb); |
| goto redo; |
| } |
| |
| /* find matching stream */ |
| if (!((startcode >= 0x1c0 && startcode <= 0x1df) || |
| (startcode >= 0x1e0 && startcode <= 0x1ef) || |
| (startcode == 0x1bd) || (startcode == 0x1fd))) |
| goto redo; |
| if (ppos) { |
| *ppos = url_ftell(s->pb) - 4; |
| } |
| len = get_be16(s->pb); |
| pts = |
| dts = AV_NOPTS_VALUE; |
| /* stuffing */ |
| for(;;) { |
| if (len < 1) |
| goto error_redo; |
| c = get_byte(s->pb); |
| len--; |
| /* XXX: for mpeg1, should test only bit 7 */ |
| if (c != 0xff) |
| break; |
| } |
| if ((c & 0xc0) == 0x40) { |
| /* buffer scale & size */ |
| get_byte(s->pb); |
| c = get_byte(s->pb); |
| len -= 2; |
| } |
| if ((c & 0xe0) == 0x20) { |
| dts = pts = get_pts(s->pb, c); |
| len -= 4; |
| if (c & 0x10){ |
| dts = get_pts(s->pb, -1); |
| len -= 5; |
| } |
| } else if ((c & 0xc0) == 0x80) { |
| /* mpeg 2 PES */ |
| #if 0 /* some streams have this field set for no apparent reason */ |
| if ((c & 0x30) != 0) { |
| /* Encrypted multiplex not handled */ |
| goto redo; |
| } |
| #endif |
| flags = get_byte(s->pb); |
| header_len = get_byte(s->pb); |
| len -= 2; |
| if (header_len > len) |
| goto error_redo; |
| len -= header_len; |
| if (flags & 0x80) { |
| dts = pts = get_pts(s->pb, -1); |
| header_len -= 5; |
| if (flags & 0x40) { |
| dts = get_pts(s->pb, -1); |
| header_len -= 5; |
| } |
| } |
| if (flags & 0x3f && header_len == 0){ |
| flags &= 0xC0; |
| av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n"); |
| } |
| if (flags & 0x01) { /* PES extension */ |
| pes_ext = get_byte(s->pb); |
| header_len--; |
| /* Skip PES private data, program packet sequence counter and P-STD buffer */ |
| skip = (pes_ext >> 4) & 0xb; |
| skip += skip & 0x9; |
| if (pes_ext & 0x40 || skip > header_len){ |
| av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext); |
| pes_ext=skip=0; |
| } |
| url_fskip(s->pb, skip); |
| header_len -= skip; |
| |
| if (pes_ext & 0x01) { /* PES extension 2 */ |
| ext2_len = get_byte(s->pb); |
| header_len--; |
| if ((ext2_len & 0x7f) > 0) { |
| id_ext = get_byte(s->pb); |
| if ((id_ext & 0x80) == 0) |
| startcode = ((startcode & 0xff) << 8) | id_ext; |
| header_len--; |
| } |
| } |
| } |
| if(header_len < 0) |
| goto error_redo; |
| url_fskip(s->pb, header_len); |
| } |
| else if( c!= 0xf ) |
| goto redo; |
| |
| if (startcode == PRIVATE_STREAM_1 && !m->psm_es_type[startcode & 0xff]) { |
| startcode = get_byte(s->pb); |
| len--; |
| if (startcode >= 0x80 && startcode <= 0xcf) { |
| /* audio: skip header */ |
| get_byte(s->pb); |
| get_byte(s->pb); |
| get_byte(s->pb); |
| len -= 3; |
| if (startcode >= 0xb0 && startcode <= 0xbf) { |
| /* MLP/TrueHD audio has a 4-byte header */ |
| get_byte(s->pb); |
| len--; |
| } |
| } |
| } |
| if(len<0) |
| goto error_redo; |
| if(dts != AV_NOPTS_VALUE && ppos){ |
| int i; |
| for(i=0; i<s->nb_streams; i++){ |
| if(startcode == s->streams[i]->id && |
| !url_is_streamed(s->pb) /* index useless on streams anyway */) { |
| ff_reduce_index(s, i); |
| av_add_index_entry(s->streams[i], *ppos, dts, 0, 0, AVINDEX_KEYFRAME /* FIXME keyframe? */); |
| } |
| } |
| } |
| |
| *pstart_code = startcode; |
| *ppts = pts; |
| *pdts = dts; |
| return len; |
| } |
| |
| static int mpegps_read_packet(AVFormatContext *s, |
| AVPacket *pkt) |
| { |
| MpegDemuxContext *m = s->priv_data; |
| AVStream *st; |
| int len, startcode, i, es_type; |
| enum CodecID codec_id = CODEC_ID_NONE; |
| enum CodecType type; |
| int64_t pts, dts, dummy_pos; //dummy_pos is needed for the index building to work |
| uint8_t dvdaudio_substream_type; |
| |
| redo: |
| len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts); |
| if (len < 0) |
| return len; |
| |
| if(startcode == 0x1bd) { |
| dvdaudio_substream_type = get_byte(s->pb); |
| url_fskip(s->pb, 3); |
| len -= 4; |
| } |
| |
| /* now find stream */ |
| for(i=0;i<s->nb_streams;i++) { |
| st = s->streams[i]; |
| if (st->id == startcode) |
| goto found; |
| } |
| |
| es_type = m->psm_es_type[startcode & 0xff]; |
| if(es_type > 0 && es_type != STREAM_TYPE_PRIVATE_DATA){ |
| if(es_type == STREAM_TYPE_VIDEO_MPEG1){ |
| codec_id = CODEC_ID_MPEG2VIDEO; |
| type = CODEC_TYPE_VIDEO; |
| } else if(es_type == STREAM_TYPE_VIDEO_MPEG2){ |
| codec_id = CODEC_ID_MPEG2VIDEO; |
| type = CODEC_TYPE_VIDEO; |
| } else if(es_type == STREAM_TYPE_AUDIO_MPEG1 || |
| es_type == STREAM_TYPE_AUDIO_MPEG2){ |
| codec_id = CODEC_ID_MP3; |
| type = CODEC_TYPE_AUDIO; |
| } else if(es_type == STREAM_TYPE_AUDIO_AAC){ |
| codec_id = CODEC_ID_AAC; |
| type = CODEC_TYPE_AUDIO; |
| } else if(es_type == STREAM_TYPE_VIDEO_MPEG4){ |
| codec_id = CODEC_ID_MPEG4; |
| type = CODEC_TYPE_VIDEO; |
| } else if(es_type == STREAM_TYPE_VIDEO_H264){ |
| codec_id = CODEC_ID_H264; |
| type = CODEC_TYPE_VIDEO; |
| } else if(es_type == STREAM_TYPE_AUDIO_AC3){ |
| codec_id = CODEC_ID_AC3; |
| type = CODEC_TYPE_AUDIO; |
| } else { |
| goto skip; |
| } |
| } else if (startcode >= 0x1e0 && startcode <= 0x1ef) { |
| static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 }; |
| unsigned char buf[8]; |
| get_buffer(s->pb, buf, 8); |
| url_fseek(s->pb, -8, SEEK_CUR); |
| if(!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1)) |
| codec_id = CODEC_ID_CAVS; |
| else |
| codec_id = CODEC_ID_PROBE; |
| type = CODEC_TYPE_VIDEO; |
| } else if (startcode >= 0x1c0 && startcode <= 0x1df) { |
| type = CODEC_TYPE_AUDIO; |
| codec_id = m->sofdec > 0 ? CODEC_ID_ADPCM_ADX : CODEC_ID_MP2; |
| } else if (startcode >= 0x80 && startcode <= 0x87) { |
| type = CODEC_TYPE_AUDIO; |
| codec_id = CODEC_ID_AC3; |
| } else if ( ( startcode >= 0x88 && startcode <= 0x8f) |
| ||( startcode >= 0x98 && startcode <= 0x9f)) { |
| /* 0x90 - 0x97 is reserved for SDDS in DVD specs */ |
| type = CODEC_TYPE_AUDIO; |
| codec_id = CODEC_ID_DTS; |
| } else if (startcode >= 0xa0 && startcode <= 0xaf) { |
| type = CODEC_TYPE_AUDIO; |
| /* 16 bit form will be handled as CODEC_ID_PCM_S16BE */ |
| codec_id = CODEC_ID_PCM_DVD; |
| } else if (startcode >= 0xb0 && startcode <= 0xbf) { |
| type = CODEC_TYPE_AUDIO; |
| codec_id = CODEC_ID_MLP; |
| } else if (startcode >= 0xc0 && startcode <= 0xcf) { |
| /* Used for both AC-3 and E-AC-3 in EVOB files */ |
| type = CODEC_TYPE_AUDIO; |
| codec_id = CODEC_ID_AC3; |
| } else if (startcode >= 0x20 && startcode <= 0x3f) { |
| type = CODEC_TYPE_SUBTITLE; |
| codec_id = CODEC_ID_DVD_SUBTITLE; |
| } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) { |
| type = CODEC_TYPE_VIDEO; |
| codec_id = CODEC_ID_VC1; |
| } else if (startcode == 0x1bd) { |
| // check dvd audio substream type |
| type = CODEC_TYPE_AUDIO; |
| switch(dvdaudio_substream_type & 0xe0) { |
| case 0xa0: codec_id = CODEC_ID_PCM_DVD; |
| break; |
| case 0x80: if((dvdaudio_substream_type & 0xf8) == 0x88) |
| codec_id = CODEC_ID_DTS; |
| else codec_id = CODEC_ID_AC3; |
| break; |
| default: av_log(s, AV_LOG_ERROR, "Unknown 0x1bd sub-stream\n"); |
| goto skip; |
| } |
| } else { |
| skip: |
| /* skip packet */ |
| url_fskip(s->pb, len); |
| goto redo; |
| } |
| /* no stream found: add a new stream */ |
| st = av_new_stream(s, startcode); |
| if (!st) |
| goto skip; |
| st->codec->codec_type = type; |
| st->codec->codec_id = codec_id; |
| if (codec_id != CODEC_ID_PCM_S16BE) |
| st->need_parsing = AVSTREAM_PARSE_FULL; |
| found: |
| if(st->discard >= AVDISCARD_ALL) |
| goto skip; |
| if ((startcode >= 0xa0 && startcode <= 0xaf) || |
| (startcode == 0x1bd && ((dvdaudio_substream_type & 0xe0) == 0xa0))) { |
| int b1, freq; |
| |
| /* for LPCM, we just skip the header and consider it is raw |
| audio data */ |
| if (len <= 3) |
| goto skip; |
| get_byte(s->pb); /* emphasis (1), muse(1), reserved(1), frame number(5) */ |
| b1 = get_byte(s->pb); /* quant (2), freq(2), reserved(1), channels(3) */ |
| get_byte(s->pb); /* dynamic range control (0x80 = off) */ |
| len -= 3; |
| freq = (b1 >> 4) & 3; |
| st->codec->sample_rate = lpcm_freq_tab[freq]; |
| st->codec->channels = 1 + (b1 & 7); |
| st->codec->bits_per_coded_sample = 16 + ((b1 >> 6) & 3) * 4; |
| st->codec->bit_rate = st->codec->channels * |
| st->codec->sample_rate * |
| st->codec->bits_per_coded_sample; |
| if (st->codec->bits_per_coded_sample == 16) |
| st->codec->codec_id = CODEC_ID_PCM_S16BE; |
| else if (st->codec->bits_per_coded_sample == 28) |
| return AVERROR(EINVAL); |
| } |
| av_new_packet(pkt, len); |
| get_buffer(s->pb, pkt->data, pkt->size); |
| pkt->pts = pts; |
| pkt->dts = dts; |
| pkt->stream_index = st->index; |
| #if 0 |
| av_log(s, AV_LOG_DEBUG, "%d: pts=%0.3f dts=%0.3f size=%d\n", |
| pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0, pkt->size); |
| #endif |
| |
| return 0; |
| } |
| |
| static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index, |
| int64_t *ppos, int64_t pos_limit) |
| { |
| int len, startcode; |
| int64_t pos, pts, dts; |
| |
| pos = *ppos; |
| #ifdef DEBUG_SEEK |
| printf("read_dts: pos=0x%"PRIx64" next=%d -> ", pos, find_next); |
| #endif |
| if (url_fseek(s->pb, pos, SEEK_SET) < 0) |
| return AV_NOPTS_VALUE; |
| |
| for(;;) { |
| len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts); |
| if (len < 0) { |
| #ifdef DEBUG_SEEK |
| printf("none (ret=%d)\n", len); |
| #endif |
| return AV_NOPTS_VALUE; |
| } |
| if (startcode == s->streams[stream_index]->id && |
| dts != AV_NOPTS_VALUE) { |
| break; |
| } |
| url_fskip(s->pb, len); |
| } |
| #ifdef DEBUG_SEEK |
| printf("pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n", pos, dts, dts / 90000.0); |
| #endif |
| *ppos = pos; |
| return dts; |
| } |
| |
| AVInputFormat mpegps_demuxer = { |
| "mpeg", |
| NULL_IF_CONFIG_SMALL("MPEG-PS format"), |
| sizeof(MpegDemuxContext), |
| mpegps_probe, |
| mpegps_read_header, |
| mpegps_read_packet, |
| NULL, |
| NULL, //mpegps_read_seek, |
| mpegps_read_dts, |
| .flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT, |
| }; |
