shithub: opus

Download patch

ref: 997fdf54e781ae1c04dee42018f35388a04fe483
parent: ab04fbb1b7d0b727636d28fc2cadb5df9febe515
author: Jean-Marc Valin <[email protected]>
date: Thu Aug 4 14:59:37 EDT 2022 

Change pitch scaling behavior wrt nFramesPerPacket

Not sure if it was the original intent, but we now reduce the
loss percentage threshold for pitch scaling as 1/nFramesPerPacket
since only the first frame will have pitch scaling anyway.
As a side effect, this brings back the original behavior of
disabling pitch scaling for 0% loss.


--- a/silk/fixed/LTP_scale_ctrl_FIX.c
+++ b/silk/fixed/LTP_scale_ctrl_FIX.c
@@ -42,7 +42,7 @@
 
     if( condCoding == CODE_INDEPENDENTLY ) {
         /* Only scale if first frame in packet */
-        round_loss = psEnc->sCmn.PacketLoss_perc + psEnc->sCmn.nFramesPerPacket;
+        round_loss = psEnc->sCmn.PacketLoss_perc * psEnc->sCmn.nFramesPerPacket;
         if ( psEnc->sCmn.LBRR_flag ) {
             /* LBRR reduces the effective loss. In practice, it does not square the loss because
                losses aren't independent, but that still seems to work best. We also never go below 2%. */
--- a/silk/float/LTP_scale_ctrl_FLP.c
+++ b/silk/float/LTP_scale_ctrl_FLP.c
@@ -41,7 +41,7 @@
 
     if( condCoding == CODE_INDEPENDENTLY ) {
         /* Only scale if first frame in packet */
-        round_loss = psEnc->sCmn.PacketLoss_perc + psEnc->sCmn.nFramesPerPacket;
+        round_loss = psEnc->sCmn.PacketLoss_perc * psEnc->sCmn.nFramesPerPacket;
         if ( psEnc->sCmn.LBRR_flag ) {
             /* LBRR reduces the effective loss. In practice, it does not square the loss because
                losses aren't independent, but that still seems to work best. We also never go below 2%. */