Avoiding work on the PLC update side

Shift computation to concealment

dnn/lpcnet_plc.c

@@ -59,6 +59,7 @@ int lpcnet_plc_init(LPCNetPLCState *st, int options) {
   int ret;
   fargan_init(&st->fargan);
   lpcnet_encoder_init(&st->enc);
+  st->analysis_pos = PLC_BUF_SIZE;
   if ((options&0x3) == LPCNET_PLC_CAUSAL) {
     st->enable_blending = 1;
   } else if ((options&0x3) == LPCNET_PLC_CODEC) {
@@ -168,20 +169,10 @@ static void replace_features(LPCNetPLCState *st, const float *features) {
 
 int lpcnet_plc_update(LPCNetPLCState *st, opus_int16 *pcm) {
   int i;
-  float x[FRAME_SIZE];
-  float plc_features[2*NB_BANDS+NB_FEATURES+1];
-  for (i=0;i<FRAME_SIZE;i++) x[i] = pcm[i];
-  burg_cepstral_analysis(plc_features, x);
-  lpcnet_compute_single_frame_features_float(&st->enc, x, st->features);
   if (st->blend) {
-    replace_features(st, st->features);
-    if (FEATURES_DELAY > 0) st->plc_net = st->plc_copy[FEATURES_DELAY-1];
-  } else {
-    queue_features(st, st->features);
-    OPUS_COPY(&plc_features[2*NB_BANDS], st->features, NB_FEATURES);
-    plc_features[2*NB_BANDS+NB_FEATURES] = 1;
-    compute_plc_pred(st, st->features, plc_features);
+    st->analysis_pos = PLC_BUF_SIZE-FRAME_SIZE;
   }
+  if (st->analysis_pos - FRAME_SIZE >= 0) st->analysis_pos -= FRAME_SIZE;
   OPUS_MOVE(st->pcm, &st->pcm[FRAME_SIZE], PLC_BUF_SIZE-FRAME_SIZE);
   for (i=0;i<FRAME_SIZE;i++) st->pcm[PLC_BUF_SIZE-FRAME_SIZE+i] = (1.f/32768.f)*pcm[i];
   st->loss_count = 0;
@@ -193,6 +184,23 @@ static const float att_table[10] = {0, 0,  -.2, -.2,  -.4, -.4,  -.8, -.8, -1.6,
 int lpcnet_plc_conceal(LPCNetPLCState *st, opus_int16 *pcm) {
   int i;
   if (st->blend == 0) {
+    int count = 0;
+    while (st->analysis_pos + FRAME_SIZE <= PLC_BUF_SIZE) {
+      float x[FRAME_SIZE];
+      float plc_features[2*NB_BANDS+NB_FEATURES+1];
+      for (i=0;i<FRAME_SIZE;i++) x[i] = 32768.f*st->pcm[st->analysis_pos+i];
+      burg_cepstral_analysis(plc_features, x);
+      lpcnet_compute_single_frame_features_float(&st->enc, x, st->features);
+      if (count > 0) {
+        if (count == 1) replace_features(st, st->features);
+        else queue_features(st, st->features);
+        OPUS_COPY(&plc_features[2*NB_BANDS], st->features, NB_FEATURES);
+        plc_features[2*NB_BANDS+NB_FEATURES] = 1;
+        compute_plc_pred(st, st->features, plc_features);
+      }
+      st->analysis_pos += FRAME_SIZE;
+      count++;
+    }
     get_fec_or_pred(st, st->features);
     queue_features(st, st->features);
     get_fec_or_pred(st, st->features);
@@ -206,9 +214,7 @@ int lpcnet_plc_conceal(LPCNetPLCState *st, opus_int16 *pcm) {
   if (st->loss_count >= 10) st->features[0] = MAX16(-10, st->features[0]+att_table[9] - 2*(st->loss_count-9));
   else st->features[0] = MAX16(-10, st->features[0]+att_table[st->loss_count]);
   fargan_synthesize_int(&st->fargan, pcm, &st->features[0]);
-  lpcnet_compute_single_frame_features(&st->enc, pcm, st->features);
-  OPUS_MOVE(&st->cont_features[0], &st->cont_features[NB_FEATURES], (CONT_VECTORS-1)*NB_FEATURES);
-  OPUS_COPY(&st->cont_features[(CONT_VECTORS-1)*NB_FEATURES], st->features, NB_FEATURES);
+  queue_features(st, st->features);
   OPUS_MOVE(st->pcm, &st->pcm[FRAME_SIZE], PLC_BUF_SIZE-FRAME_SIZE);
   for (i=0;i<FRAME_SIZE;i++) st->pcm[PLC_BUF_SIZE-FRAME_SIZE+i] = (1.f/32768.f)*pcm[i];
   st->blend = 1;

dnn/lpcnet_private.h

@@ -60,6 +60,7 @@ struct LPCNetPLCState {
   int fec_read_pos;
   int fec_fill_pos;
   int fec_skip;
+  int analysis_pos;
   float pcm[PLC_BUF_SIZE];
   int blend;
   float features[NB_TOTAL_FEATURES];