---
libavformat/mp3dec.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 55 insertions(+)
diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c
index bdf11f8..7bdb8b1 100644
--- a/libavformat/mp3dec.c
+++ b/libavformat/mp3dec.c
@@ -132,7 +132,17 @@ static void read_xing_toc(AVFormatContext *s, int64_t
filesize, int64_t duration
static int mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
MPADecodeHeader *c, uint32_t spf)
{
+#define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
+#define MID_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
+
+ float f;
uint32_t v;
+
+ char version[10];
+
+ uint32_t peak = 0;
+ int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
+
MP3DecContext *mp3 = s->priv_data;
const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
@@ -153,6 +163,51 @@ static int mp3_parse_info_tag(AVFormatContext *s, AVStream
*st,
st->time_base));
}
+ avio_skip(s->pb, 3);
+
+ /* VBR quality */
+ avio_r8(s->pb);
+
+ /* Encoder short version string */
+ avio_get_str(s->pb, 9, version, 10);
+
+ /* Info Tag revision + VBR method */
+ avio_r8(s->pb);
+
+ /* Lowpass filter value */
+ avio_r8(s->pb);
+
+ /* ReplayGain */
+ v = avio_rb32(s->pb);
+ f = (v << 5) / (float) (1 << 28);
+
+ if (f > 0)
+ peak = f * 100000;
+
+ v = avio_rb16(s->pb);
+
+ if (MID_BITS(v, 13, 15) == 1) { /* Radio Replay Gain */
+ f = MID_BITS(v, 0, 8) / 10.f;
+
+ if (v & (1 << 9))
+ f *= -1;
+
+ r_gain = f * 100000;
+ }
+
+ v = avio_rb16(s->pb);
+
+ if (MID_BITS(v, 13, 15) == 2) { /* Audiophile Replay Gain */
+ f = MID_BITS(v, 0, 8) / 10.f;
+
+ if (v & (1 << 9))
+ f *= -1;
+
+ a_gain = f * 100000;
+ }
+
+ ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
+
return 0;
}
--
1.9.1
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