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Merge commit 'fbd8e042107ec63e0ddf155588c59dcb76007641'

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* commit 'fbd8e042107ec63e0ddf155588c59dcb76007641':
  mp3dec: move XING/Info and VBRI parsing into their own functions

Conflicts:
	libavformat/mp3dec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-04-17 22:07:45 +02:00
commit 39edcadc07
1 changed files with 61 additions and 44 deletions
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105
libavformat/mp3dec.c
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@ -41,11 +41,12 @@
typedef struct { typedef struct {
AVClass *class; AVClass *class;
int64_t filesize; int64_t filesize;
int64_t header_filesize;
int xing_toc; int xing_toc;
int start_pad; int start_pad;
int end_pad; int end_pad;
int usetoc; int usetoc;
unsigned frames; /* Total number of frames in file */
unsigned header_filesize; /* Total number of bytes in the stream */
int is_cbr; int is_cbr;
} MP3DecContext; } MP3DecContext;
@ -119,44 +120,29 @@ static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration
mp3->xing_toc = 1; mp3->xing_toc = 1;
} }
/**
* Try to find Xing/Info/VBRI tags and compute duration from info therein static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
*/ MPADecodeHeader *c, uint32_t spf)
static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
{ {
uint32_t v;
MP3DecContext *mp3 = s->priv_data; 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}}; 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 */ /* 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); v = avio_rb32(s->pb);
is_cbr = v == MKBETAG('I', 'n', 'f', 'o'); mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
if (v == MKBETAG('X', 'i', 'n', 'g') || is_cbr) { if (v == MKBETAG('X', 'i', 'n', 'g') || mp3->is_cbr) {
v = avio_rb32(s->pb); v = avio_rb32(s->pb);
if(v & XING_FLAG_FRAMES) if (v & XING_FLAG_FRAMES)
frames = avio_rb32(s->pb); mp3->frames = avio_rb32(s->pb);
if(v & XING_FLAG_SIZE) if (v & XING_FLAG_SIZE)
size = avio_rb32(s->pb); mp3->header_filesize = avio_rb32(s->pb);
if (v & XING_FLAG_TOC) if (v & XING_FLAG_TOC)
read_xing_toc(s, size, av_rescale_q(frames, (AVRational){spf, c.sample_rate}, read_xing_toc(s, mp3->header_filesize,
st->time_base)); av_rescale_q(mp3->frames,
(AVRational){spf, c->sample_rate},
st->time_base));
if(v & 8) if(v & 8)
avio_skip(s->pb, 4); 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; st->skip_samples = mp3->start_pad + 528 + 1;
if (!st->start_time) if (!st->start_time)
st->start_time = av_rescale_q(st->skip_samples, st->start_time = av_rescale_q(st->skip_samples,
(AVRational){1, c.sample_rate}, (AVRational){1, c->sample_rate},
st->time_base); st->time_base);
av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad); 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) */ /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
avio_seek(s->pb, base + 4 + 32, SEEK_SET); avio_seek(s->pb, base + 4 + 32, SEEK_SET);
v = avio_rb32(s->pb); v = avio_rb32(s->pb);
if(v == MKBETAG('V', 'B', 'R', 'I')) { if (v == MKBETAG('V', 'B', 'R', 'I')) {
/* Check tag version */ /* Check tag version */
if(avio_rb16(s->pb) == 1) { if (avio_rb16(s->pb) == 1) {
/* skip delay and quality */ /* skip delay and quality */
avio_skip(s->pb, 4); avio_skip(s->pb, 4);
size = avio_rb32(s->pb); mp3->header_filesize = avio_rb32(s->pb);
frames = 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; return -1;
/* Skip the vbr tag frame */ /* Skip the vbr tag frame */
avio_seek(s->pb, base + vbrtag_size, SEEK_SET); avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
if(frames) if (mp3->frames)
st->duration = av_rescale_q(frames, (AVRational){spf, c.sample_rate}, st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
st->time_base); st->time_base);
if (size && frames && !is_cbr) if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
st->codec->bit_rate = av_rescale(size, 8 * c.sample_rate, frames * (int64_t)spf); st->codec->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
mp3->is_cbr = is_cbr;
mp3->header_filesize = size;
return 0; return 0;
} }