shithub: opus

Download patch

ref: 6fbfed6a0b927f0b54340081675c116955dd3705
parent: ae7dc8a13fb61a50204c5b28aac3c1c4c2e1c0dc
author: Jean-Marc Valin <[email protected]>
date: Fri Sep 13 13:16:38 EDT 2013 

Allowing surround to use lower bandwidth than fullband


--- a/src/opus_multistream_encoder.c
+++ b/src/opus_multistream_encoder.c
@@ -747,7 +747,18 @@
       opus_encoder_ctl(enc, OPUS_SET_BITRATE(bitrates[s]));
       if (st->surround)
       {
-         opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_FULLBAND));
+         opus_int32 equiv_rate;
+         equiv_rate = st->bitrate_bps;
+         if (frame_size*50 < Fs)
+            equiv_rate -= 60*(Fs/frame_size - 50)*st->layout.nb_channels;
+         if (equiv_rate > 112000)
+            opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_FULLBAND));
+         else if (equiv_rate > 76000)
+            opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_SUPERWIDEBAND));
+         else if (equiv_rate > 48000)
+            opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_WIDEBAND));
+         else
+            opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_NARROWBAND));
          if (s < st->layout.nb_coupled_streams)
          {
             /* To preserve the spatial image, force stereo CELT on coupled streams */