Convert CNG into C++ and remove it from AudioDecoder

webrtc/modules/audio_coding/neteq/neteq_impl.cc

Index: webrtc/modules/audio_coding/neteq/neteq_impl.cc
diff --git a/webrtc/modules/audio_coding/neteq/neteq_impl.cc b/webrtc/modules/audio_coding/neteq/neteq_impl.cc
index db37e716d66dde966a4cac42f10dd47166c4f42c..f54d2c5cf6c778e8f30fa68b521a9a3fc66e6dbe 100644
--- a/webrtc/modules/audio_coding/neteq/neteq_impl.cc
+++ b/webrtc/modules/audio_coding/neteq/neteq_impl.cc
@@ -667,15 +667,17 @@ int NetEqImpl::InsertPacketInternal(const WebRtcRTPHeader& rtp_header,
   // Update bandwidth estimate, if the packet is not sync-packet.

[hlundin-webrtc, 2016/04/11 11:33:00]

Update the comment to mention that CNG packets are excluded too.

[ossu, 2016/04/11 12:59:57]

Acknowledged.

   if (!packet_list.empty() && !packet_list.front()->sync_packet) {
     // The list can be empty here if we got nothing but DTMF payloads.
-    AudioDecoder* decoder =
-        decoder_database_->GetDecoder(main_header.payloadType);
-    assert(decoder);  // Should always get a valid object, since we have
-                      // already checked that the payload types are known.
-    decoder->IncomingPacket(packet_list.front()->payload,
-                            packet_list.front()->payload_length,
-                            packet_list.front()->header.sequenceNumber,
-                            packet_list.front()->header.timestamp,
-                            receive_timestamp);
+    if (!decoder_database_->IsComfortNoise(main_header.payloadType)) {
+      AudioDecoder* decoder =
+          decoder_database_->GetDecoder(main_header.payloadType);
+      assert(decoder);  // Should always get a valid object, since we have
+      // already checked that the payload types are known.
+      decoder->IncomingPacket(packet_list.front()->payload,
+                              packet_list.front()->payload_length,
+                              packet_list.front()->header.sequenceNumber,
+                              packet_list.front()->header.timestamp,
+                              receive_timestamp);
+    }
   }
 
   if (nack_enabled_) {
@@ -728,14 +730,18 @@ int NetEqImpl::InsertPacketInternal(const WebRtcRTPHeader& rtp_header,
     const RTPHeader* rtp_header = packet_buffer_->NextRtpHeader();
     assert(rtp_header);
     int payload_type = rtp_header->payloadType;
-    AudioDecoder* decoder = decoder_database_->GetDecoder(payload_type);
-    assert(decoder);  // Payloads are already checked to be valid.
+    size_t channels = 1;
+    if (!decoder_database_->IsComfortNoise(payload_type)) {
+      AudioDecoder* decoder = decoder_database_->GetDecoder(payload_type);
+      assert(decoder);  // Payloads are already checked to be valid.
+      channels = decoder->Channels();
+    }
     const DecoderDatabase::DecoderInfo* decoder_info =
         decoder_database_->GetDecoderInfo(payload_type);
     assert(decoder_info);
     if (decoder_info->fs_hz != fs_hz_ ||
-        decoder->Channels() != algorithm_buffer_->Channels()) {
-      SetSampleRateAndChannels(decoder_info->fs_hz, decoder->Channels());
+        channels != algorithm_buffer_->Channels()) {
+      SetSampleRateAndChannels(decoder_info->fs_hz, channels);
     }
     if (nack_enabled_) {
       RTC_DCHECK(nack_);
@@ -1297,9 +1303,9 @@ int NetEqImpl::Decode(PacketList* packet_list, Operations* operation,
       decoder->Reset();
 
     // Reset comfort noise decoder.
-    AudioDecoder* cng_decoder = decoder_database_->GetActiveCngDecoder();
+    CNG_dec_inst* cng_decoder = decoder_database_->GetActiveCngDecoder();
     if (cng_decoder)
-      cng_decoder->Reset();
+      WebRtcCng_InitDec(cng_decoder);
 
     reset_decoder_ = false;
   }
@@ -1955,7 +1961,7 @@ int NetEqImpl::ExtractPackets(size_t required_samples,
           stats_.SecondaryDecodedSamples(packet_duration);
         }
       }
-    } else {
+    } else if (!decoder_database_->IsComfortNoise(packet->header.payloadType)) {
       LOG(LS_WARNING) << "Unknown payload type "
                       << static_cast<int>(packet->header.payloadType);
       assert(false);
@@ -2023,9 +2029,9 @@ void NetEqImpl::SetSampleRateAndChannels(int fs_hz, size_t channels) {
     mute_factor_array_[i] = 16384;  // 1.0 in Q14.
   }
 
-  AudioDecoder* cng_decoder = decoder_database_->GetActiveCngDecoder();
+  CNG_dec_inst* cng_decoder = decoder_database_->GetActiveCngDecoder();
   if (cng_decoder)
-    cng_decoder->Reset();
+    WebRtcCng_InitDec(cng_decoder);
 
   // Reinit post-decode VAD with new sample rate.
   assert(vad_.get());  // Cannot be NULL here.