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authorMichael Niedermayer <michaelni@gmx.at>2014-04-17 22:07:45 +0200
committerMichael Niedermayer <michaelni@gmx.at>2014-04-17 22:27:17 +0200
commit39edcadc07e90c551596e74a932b603eea0c8b01 (patch)
treeb197f9d9e96d441aa2b38e6f7e0234f6e7562ed2 /libavformat/mp3dec.c
parentd35efda21a146ad437e194cf124e3ca170bfc82e (diff)
parentfbd8e042107ec63e0ddf155588c59dcb76007641 (diff)
downloadffmpeg-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>
Diffstat (limited to 'libavformat/mp3dec.c')
-rw-r--r--libavformat/mp3dec.c105
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;
}