[FFmpeg-soc] [soc]: r4276 - seek_api/mpeg.c
spyfeng
subversion at mplayerhq.hu
Sat May 16 18:59:43 CEST 2009
Author: spyfeng
Date: Sat May 16 18:59:43 2009
New Revision: 4276
Log:
add mpeg.c to be modified for implement mpegps_read_seek() function
Added:
seek_api/mpeg.c
Added: seek_api/mpeg.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ seek_api/mpeg.c Sat May 16 18:59:43 2009 (r4276)
@@ -0,0 +1,611 @@
+/*
+ * 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;
+ }else if((*p&0xF0) == 0x30){
+ pes1= p[0]&p[2]&p[4]&p[5]&p[7]&p[9]&1;
+ }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 av_uninit(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_TRUEHD;
+ } 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,
+};
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