File opus-Silk-CNG-adapts-faster.patch of Package opus.14015
From 3ebf4ad86de2469572f7fa2bd6451469e7867c8f Mon Sep 17 00:00:00 2001
From: Felicia Lim <flim@google.com>
Date: Fri, 31 May 2019 13:58:44 -0700
Subject: [PATCH] Silk CNG adapts faster to received packets with lower gains
---
silk/CNG.c | 4 ++++
silk/define.h | 1 +
2 files changed, 5 insertions(+)
diff --git a/silk/CNG.c b/silk/CNG.c
index ef8e38df..2a910099 100644
--- a/silk/CNG.c
+++ b/silk/CNG.c
@@ -118,6 +118,10 @@ void silk_CNG(
/* Smooth gains */
for( i = 0; i < psDec->nb_subfr; i++ ) {
psCNG->CNG_smth_Gain_Q16 += silk_SMULWB( psDecCtrl->Gains_Q16[ i ] - psCNG->CNG_smth_Gain_Q16, CNG_GAIN_SMTH_Q16 );
+ /* If the smoothed gain is 3 dB greater than this subframe's gain, use this subframe's gain to adapt faster. */
+ if( silk_SMULWW( psCNG->CNG_smth_Gain_Q16, CNG_GAIN_SMTH_THRESHOLD_Q16 ) > psDecCtrl->Gains_Q16[ i ] ) {
+ psCNG->CNG_smth_Gain_Q16 = psDecCtrl->Gains_Q16[ i ];
+ }
}
}
diff --git a/silk/define.h b/silk/define.h
index 247cb0bf..491c86f3 100644
--- a/silk/define.h
+++ b/silk/define.h
@@ -225,6 +225,7 @@ extern "C"
/* Defines for CN generation */
#define CNG_BUF_MASK_MAX 255 /* 2^floor(log2(MAX_FRAME_LENGTH))-1 */
#define CNG_GAIN_SMTH_Q16 4634 /* 0.25^(1/4) */
+#define CNG_GAIN_SMTH_THRESHOLD_Q16 46396 /* -3 dB */
#define CNG_NLSF_SMTH_Q16 16348 /* 0.25 */
#ifdef __cplusplus
--
2.11.0