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authorClément Bœsch <ubitux@gmail.com>2012-05-09 22:39:40 +0200
committerClément Bœsch <ubitux@gmail.com>2012-05-13 16:49:17 +0200
commitca297513f034198029084b4af33ac4c29ab83bce (patch)
treeb13ed08cbd40b4b4a7f981e4f0105b58d55064b1 /libavformat/mp3enc.c
parent1f2f031c2fc3a0f5439a2f3fb22236c8e3d8f69f (diff)
downloadffmpeg-ca297513f034198029084b4af33ac4c29ab83bce.tar.gz
lavf/mp3enc: support MPEG-2 and MPEG-2.5 sample rates when writing Xing header.
Diffstat (limited to 'libavformat/mp3enc.c')
-rw-r--r--libavformat/mp3enc.c18
1 files changed, 11 insertions, 7 deletions
diff --git a/libavformat/mp3enc.c b/libavformat/mp3enc.c
index 7dec8245f0..8a9f788faa 100644
--- a/libavformat/mp3enc.c
+++ b/libavformat/mp3enc.c
@@ -121,17 +121,21 @@ static int mp3_write_xing(AVFormatContext *s)
int64_t xing_offset;
int32_t header, mask;
MPADecodeHeader c;
- int srate_idx, i, channels;
+ int srate_idx, ver = 0, i, channels;
int needed;
if (!s->pb->seekable)
return 0;
- for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++)
- if (avpriv_mpa_freq_tab[i] == codec->sample_rate) {
- srate_idx = i;
- break;
- }
+ for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
+ const uint16_t base_freq = avpriv_mpa_freq_tab[i];
+ if (codec->sample_rate == base_freq) ver = 0x3; // MPEG 1
+ else if (codec->sample_rate == base_freq / 2) ver = 0x2; // MPEG 2
+ else if (codec->sample_rate == base_freq / 4) ver = 0x0; // MPEG 2.5
+ else continue;
+ srate_idx = i;
+ break;
+ }
if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {
av_log(s, AV_LOG_WARNING, "Unsupported sample rate, not writing Xing header.\n");
return -1;
@@ -145,7 +149,7 @@ static int mp3_write_xing(AVFormatContext *s)
/* dummy MPEG audio header */
header = 0xff << 24; // sync
- header |= (0x7 << 5 | 0x3 << 3 | 0x1 << 1 | 0x1) << 16; // sync/mpeg-1/layer 3/no crc*/
+ header |= (0x7 << 5 | ver << 3 | 0x1 << 1 | 0x1) << 16; // sync/audio-version/layer 3/no crc*/
header |= (srate_idx << 2) << 8;
header |= channels << 6;