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author | Michael Niedermayer <michaelni@gmx.at> | 2014-04-17 22:07:45 +0200 |
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committer | Michael Niedermayer <michaelni@gmx.at> | 2014-04-17 22:27:17 +0200 |
commit | 39edcadc07e90c551596e74a932b603eea0c8b01 (patch) | |
tree | b197f9d9e96d441aa2b38e6f7e0234f6e7562ed2 | |
parent | d35efda21a146ad437e194cf124e3ca170bfc82e (diff) | |
parent | fbd8e042107ec63e0ddf155588c59dcb76007641 (diff) | |
download | ffmpeg-39edcadc07e90c551596e74a932b603eea0c8b01.tar.gz |
Merge commit 'fbd8e042107ec63e0ddf155588c59dcb76007641'
* commit 'fbd8e042107ec63e0ddf155588c59dcb76007641':
mp3dec: move XING/Info and VBRI parsing into their own functions
Conflicts:
libavformat/mp3dec.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
-rw-r--r-- | libavformat/mp3dec.c | 105 |
1 files changed, 61 insertions, 44 deletions
diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index c2b3467bf4..e1bab0ee59 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -41,11 +41,12 @@ typedef struct { AVClass *class; int64_t filesize; - int64_t header_filesize; int xing_toc; int start_pad; int end_pad; int usetoc; + unsigned frames; /* Total number of frames in file */ + unsigned header_filesize; /* Total number of bytes in the stream */ int is_cbr; } MP3DecContext; @@ -119,44 +120,29 @@ static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration mp3->xing_toc = 1; } -/** - * Try to find Xing/Info/VBRI tags and compute duration from info therein - */ -static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) + +static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, + MPADecodeHeader *c, uint32_t spf) { + uint32_t v; MP3DecContext *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 */ static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}}; - MPADecodeHeader c; - int vbrtag_size = 0; - int is_cbr; - - v = avio_rb32(s->pb); - if(ff_mpa_check_header(v) < 0) - return -1; - - if (avpriv_mpegaudio_decode_header(&c, v) == 0) - vbrtag_size = c.frame_size; - if(c.layer != 3) - return -1; - - spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */ /* Check for Xing / Info tag */ - avio_skip(s->pb, xing_offtbl[c.lsf == 1][c.nb_channels == 1]); + avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]); v = avio_rb32(s->pb); - is_cbr = v == MKBETAG('I', 'n', 'f', 'o'); - if (v == MKBETAG('X', 'i', 'n', 'g') || is_cbr) { + mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o'); + if (v == MKBETAG('X', 'i', 'n', 'g') || mp3->is_cbr) { v = avio_rb32(s->pb); - if(v & XING_FLAG_FRAMES) - frames = avio_rb32(s->pb); - if(v & XING_FLAG_SIZE) - size = avio_rb32(s->pb); + if (v & XING_FLAG_FRAMES) + mp3->frames = avio_rb32(s->pb); + if (v & XING_FLAG_SIZE) + mp3->header_filesize = avio_rb32(s->pb); if (v & XING_FLAG_TOC) - read_xing_toc(s, size, av_rescale_q(frames, (AVRational){spf, c.sample_rate}, - st->time_base)); + read_xing_toc(s, mp3->header_filesize, + av_rescale_q(mp3->frames, + (AVRational){spf, c->sample_rate}, + st->time_base)); if(v & 8) avio_skip(s->pb, 4); @@ -169,39 +155,70 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) st->skip_samples = mp3->start_pad + 528 + 1; if (!st->start_time) st->start_time = av_rescale_q(st->skip_samples, - (AVRational){1, c.sample_rate}, + (AVRational){1, c->sample_rate}, st->time_base); av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad); } } +} + +static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base) +{ + uint32_t v; + MP3DecContext *mp3 = s->priv_data; /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */ avio_seek(s->pb, base + 4 + 32, SEEK_SET); v = avio_rb32(s->pb); - if(v == MKBETAG('V', 'B', 'R', 'I')) { + if (v == MKBETAG('V', 'B', 'R', 'I')) { /* Check tag version */ - if(avio_rb16(s->pb) == 1) { + if (avio_rb16(s->pb) == 1) { /* skip delay and quality */ avio_skip(s->pb, 4); - size = avio_rb32(s->pb); - frames = avio_rb32(s->pb); + mp3->header_filesize = avio_rb32(s->pb); + mp3->frames = avio_rb32(s->pb); } } +} - if(!frames && !size) +/** + * Try to find Xing/Info/VBRI tags and compute duration from info therein + */ +static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) +{ + uint32_t v, spf; + MPADecodeHeader c; + int vbrtag_size = 0; + MP3DecContext *mp3 = s->priv_data; + + v = avio_rb32(s->pb); + if(ff_mpa_check_header(v) < 0) + return -1; + + if (avpriv_mpegaudio_decode_header(&c, v) == 0) + vbrtag_size = c.frame_size; + if(c.layer != 3) + return -1; + + spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */ + + mp3->frames = 0; + mp3->header_filesize = 0; + + mp3_parse_info_tag(s, st, &c, spf); + mp3_parse_vbri_tag(s, st, base); + + if (!mp3->frames && !mp3->header_filesize) return -1; /* Skip the vbr tag frame */ avio_seek(s->pb, base + vbrtag_size, SEEK_SET); - if(frames) - st->duration = av_rescale_q(frames, (AVRational){spf, c.sample_rate}, + if (mp3->frames) + st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate}, st->time_base); - if (size && frames && !is_cbr) - st->codec->bit_rate = av_rescale(size, 8 * c.sample_rate, frames * (int64_t)spf); - - mp3->is_cbr = is_cbr; - mp3->header_filesize = size; + if (mp3->header_filesize && mp3->frames && !mp3->is_cbr) + st->codec->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf); return 0; } |