diff options
Diffstat (limited to 'libavformat/mp3dec.c')
| -rw-r--r-- | libavformat/mp3dec.c | 103 |
1 files changed, 67 insertions, 36 deletions
diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index d81d0fc..5bd0e96 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -2,20 +2,20 @@ * MP3 demuxer * Copyright (c) 2003 Fabrice Bellard * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -29,6 +29,12 @@ #include "id3v1.h" #include "libavcodec/mpegaudiodecheader.h" +typedef struct { + int64_t filesize; + int start_pad; + int end_pad; +} MP3Context; + /* mp3 read */ static int mp3_read_probe(AVProbeData *p) @@ -63,31 +69,13 @@ static int mp3_read_probe(AVProbeData *p) } // keep this in sync with ac3 probe, both need to avoid // issues with MPEG-files! - if (first_frames >= 4) return AVPROBE_SCORE_MAX / 2 + 1; - - if (max_frames) { - int pes = 0, i; - unsigned int code = -1; - -#define VIDEO_ID 0x000001e0 -#define AUDIO_ID 0x000001c0 - /* do a search for mpegps headers to be able to properly bias - * towards mpegps if we detect this stream as both. */ - for (i = 0; i<p->buf_size; i++) { - code = (code << 8) + p->buf[i]; - if ((code & 0xffffff00) == 0x100) { - if ((code & 0x1f0) == VIDEO_ID) pes++; - else if((code & 0x1e0) == AUDIO_ID) pes++; - } - } - - if (pes) - max_frames = (max_frames + pes - 1) / pes; - } - if (max_frames > 500) return AVPROBE_SCORE_MAX / 2; - else if (max_frames >= 4) return AVPROBE_SCORE_MAX / 4; - else if (max_frames >= 1) return 1; - else return 0; + if (first_frames>=4) return AVPROBE_SCORE_MAX/2+1; + else if(max_frames>200)return AVPROBE_SCORE_MAX/2; + else if(max_frames>=4) return AVPROBE_SCORE_MAX/4; + else if(ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size) + return AVPROBE_SCORE_MAX/8; + else if(max_frames>=1) return 1; + else return 0; //mpegps_mp3_unrecognized_format.mpg has max_frames=3 } @@ -96,6 +84,7 @@ static int mp3_read_probe(AVProbeData *p) */ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) { + MP3Context *mp3 = s->priv_data; uint32_t v, spf; unsigned frames = 0; /* Total number of frames in file */ unsigned size = 0; /* Total number of bytes in the stream */ @@ -121,6 +110,20 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) frames = avio_rb32(s->pb); if(v & 0x2) size = avio_rb32(s->pb); + if(v & 4) + avio_skip(s->pb, 100); + if(v & 8) + avio_skip(s->pb, 4); + + v = avio_rb32(s->pb); + if(v == MKBETAG('L', 'A', 'M', 'E') || v == MKBETAG('L', 'a', 'v', 'f')) { + avio_skip(s->pb, 21-4); + v= avio_rb24(s->pb); + mp3->start_pad = v>>12; + mp3-> end_pad = v&4095; + st->skip_samples = mp3->start_pad + 528 + 1; + av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad); + } } /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */ @@ -154,6 +157,7 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) static int mp3_read_header(AVFormatContext *s) { + MP3Context *mp3 = s->priv_data; AVStream *st; int64_t off; @@ -163,17 +167,21 @@ static int mp3_read_header(AVFormatContext *s) st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_id = AV_CODEC_ID_MP3; - st->need_parsing = AVSTREAM_PARSE_FULL; + st->need_parsing = AVSTREAM_PARSE_FULL_RAW; st->start_time = 0; // lcm of all mp3 sample rates avpriv_set_pts_info(st, 64, 1, 14112000); + s->pb->maxsize = -1; off = avio_tell(s->pb); if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) ff_id3v1_read(s); + if(s->pb->seekable) + mp3->filesize = avio_size(s->pb); + if (mp3_parse_vbr_tags(s, st, off) < 0) avio_seek(s->pb, off, SEEK_SET); @@ -185,15 +193,26 @@ static int mp3_read_header(AVFormatContext *s) static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt) { - int ret; - - ret = av_get_packet(s->pb, pkt, MP3_PACKET_SIZE); - if (ret < 0) - return ret; + MP3Context *mp3 = s->priv_data; + int ret, size; + int64_t pos; + + size= MP3_PACKET_SIZE; + pos = avio_tell(s->pb); + if(mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize) + size= FFMIN(size, mp3->filesize - pos); + + ret= av_get_packet(s->pb, pkt, size); + if (ret <= 0) { + if(ret<0) + return ret; + return AVERROR_EOF; + } + pkt->flags &= ~AV_PKT_FLAG_CORRUPT; pkt->stream_index = 0; - if (ret > ID3v1_TAG_SIZE && + if (ret >= ID3v1_TAG_SIZE && memcmp(&pkt->data[ret - ID3v1_TAG_SIZE], "TAG", 3) == 0) ret -= ID3v1_TAG_SIZE; @@ -203,12 +222,24 @@ static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt) return ret; } +static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) +{ + MP3Context *mp3 = s->priv_data; + AVStream *st = s->streams[stream_index]; + + st->skip_samples = timestamp <= 0 ? mp3->start_pad + 528 + 1 : 0; + + return -1; +} + AVInputFormat ff_mp3_demuxer = { .name = "mp3", .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"), + .priv_data_size = sizeof(MP3Context), .read_probe = mp3_read_probe, .read_header = mp3_read_header, .read_packet = mp3_read_packet, + .read_seek = read_seek, .flags = AVFMT_GENERIC_INDEX, .extensions = "mp2,mp3,m2a", /* XXX: use probe */ }; |
