[SCM] libav/experimental: libmp3lame: add comments about CBR/VBR modes

[siretart at users.alioth.debian.org]

The following commit has been merged in the experimental branch:
commit 292dbe5e8a95d38c1324b0432fbaca67f8fe4b73
Author: Timothy Gu <timothygu99 at gmail.com>
Date:   Wed Oct 23 20:57:36 2013 -0700

    libmp3lame: add comments about CBR/VBR modes

diff --git a/libavcodec/libmp3lame.c b/libavcodec/libmp3lame.c
index 6da68ad..fbb4032 100644
--- a/libavcodec/libmp3lame.c
+++ b/libavcodec/libmp3lame.c
@@ -110,11 +110,11 @@ static av_cold int mp3lame_encode_init(AVCodecContext *avctx)
         lame_set_quality(s->gfp, avctx->compression_level);
 
     /* rate control */
-    if (avctx->flags & CODEC_FLAG_QSCALE) {
+    if (avctx->flags & CODEC_FLAG_QSCALE) { // VBR
         lame_set_VBR(s->gfp, vbr_default);
         lame_set_VBR_quality(s->gfp, avctx->global_quality / (float)FF_QP2LAMBDA);
     } else {
-        if (avctx->bit_rate)
+        if (avctx->bit_rate)                // CBR
             lame_set_brate(s->gfp, avctx->bit_rate / 1000);
     }
 

-- 
Libav/FFmpeg packaging