ref: 787eee29b87f06390fb3a2f615a525205a84d1f4
parent: fab6397ae6b7ba9f500c87ea8b457570804b8bb0
author: Felicia Lim <flim@google.com>
date: Wed Apr 6 07:23:21 EDT 2016
Turn on CELT's PLC only if there are >=2 packets received consecutively. Avoids generating comfort noise with unwanted tones in DTX mode.
--- a/celt/celt_decoder.c
+++ b/celt/celt_decoder.c
@@ -82,6 +82,7 @@
int error;
int last_pitch_index;
int loss_count;
+ int skip_plc;
int postfilter_period;
int postfilter_period_old;
opus_val16 postfilter_gain;
@@ -164,8 +165,6 @@
st->signalling = 1;
st->arch = opus_select_arch();
- st->loss_count = 0;
-
opus_custom_decoder_ctl(st, OPUS_RESET_STATE);
return OPUS_OK;
@@ -447,7 +446,7 @@
loss_count = st->loss_count;
start = st->start;
- noise_based = loss_count >= 5 || start != 0;
+ noise_based = loss_count >= 5 || start != 0 || st->skip_plc;
if (noise_based)
{
/* Noise-based PLC/CNG */
@@ -832,6 +831,10 @@
return frame_size/st->downsample;
}
+ /* Check if there are at least two packets received consecutively before
+ * turning on the pitch-based PLC */
+ st->skip_plc = st->loss_count != 0;
+
if (dec == NULL)
{
ec_dec_init(&_dec,(unsigned char*)data,len);
@@ -1198,6 +1201,7 @@
((char*)&st->DECODER_RESET_START - (char*)st));
for (i=0;i<2*st->mode->nbEBands;i++)
oldLogE[i]=oldLogE2[i]=-QCONST16(28.f,DB_SHIFT);
+ st->skip_plc = 1;
}
break;
case OPUS_GET_PITCH_REQUEST: