TimestampScaler no longer depends on NetEqDecoder to figure out scaling.

webrtc/modules/audio_coding/neteq/timestamp_scaler.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/modules/audio_coding/neteq/timestamp_scaler.h"
 
 #include "webrtc/modules/audio_coding/neteq/decoder_database.h"
-#include "webrtc/modules/audio_coding/neteq/defines.h"
 #include "webrtc/system_wrappers/include/logging.h"
 
 namespace webrtc {
 
 void TimestampScaler::Reset() {
   first_packet_received_ = false;
 }
 
 void TimestampScaler::ToInternal(Packet* packet) {
   if (!packet) {
@@ skipping 11 matching lines @@
 }
 
 uint32_t TimestampScaler::ToInternal(uint32_t external_timestamp,
                                      uint8_t rtp_payload_type) {
   const DecoderDatabase::DecoderInfo* info =
       decoder_database_.GetDecoderInfo(rtp_payload_type);
   if (!info) {
     // Payload type is unknown. Do not scale.
     return external_timestamp;
   }
-  switch (info->codec_type) {
-    case NetEqDecoder::kDecoderG722:
-    case NetEqDecoder::kDecoderG722_2ch: {
-      // Use timestamp scaling with factor 2 (two output samples per RTP
-      // timestamp).
-      numerator_ = 2;
-      denominator_ = 1;
-      break;
-    }
-    case NetEqDecoder::kDecoderAVT:
-    case NetEqDecoder::kDecoderCNGnb:
-    case NetEqDecoder::kDecoderCNGwb:
-    case NetEqDecoder::kDecoderCNGswb32kHz:
-    case NetEqDecoder::kDecoderCNGswb48kHz: {
-      // Do not change the timestamp scaling settings for DTMF or CNG.
-      break;
-    }
-    default: {
-      // Do not use timestamp scaling for any other codec.
-      numerator_ = 1;
-      denominator_ = 1;
-      break;
+  if (!(info->IsComfortNoise() || info->IsDtmf())) {
+    // Do not change the timestamp scaling settings for DTMF or CNG.
+    numerator_ = info->SampleRateHz();
+    if (info->codec_type == NetEqDecoder::kDecoderArbitrary) {
+      // We have no format mapping for "arbitrary" external codecs, so we cannot
+      // support timestamp scaling of them.
+      denominator_ = numerator_;
+    } else {
+      denominator_ = info->GetFormat().clockrate_hz;
     }
   }
-
-  if (!(numerator_ == 1 && denominator_ == 1)) {
+  if (numerator_ != denominator_) {
     // We have a scale factor != 1.
     if (!first_packet_received_) {
       external_ref_ = external_timestamp;
       internal_ref_ = external_timestamp;
       first_packet_received_ = true;
     }
-    int64_t external_diff = external_timestamp - external_ref_;
+    int64_t external_diff = int64_t{external_timestamp} - external_ref_;

[ossu, 2016/08/26 11:20:51]

These lines did unsigned 32 bit subtractions and put the result in an int64_t,
causing negative values to be 4 billion something. Still seemed to work, but
this is more correct.

[kwiberg-webrtc, 2016/08/26 11:40:57]

Acknowledged.

Consider making it const too.

[ossu, 2016/08/26 11:47:31]

Acknowledged.

     assert(denominator_ > 0);  // Should not be possible.
     external_ref_ = external_timestamp;
     internal_ref_ += (external_diff * numerator_) / denominator_;
     return internal_ref_;
   } else {
     // No scaling.
     return external_timestamp;
   }
 }
 
 
 uint32_t TimestampScaler::ToExternal(uint32_t internal_timestamp) const {
-  if (!first_packet_received_ || (numerator_ == 1 && denominator_ == 1)) {
+  if (!first_packet_received_ || (numerator_ == denominator_)) {
     // Not initialized, or scale factor is 1.
     return internal_timestamp;
   } else {
-    int64_t internal_diff = internal_timestamp - internal_ref_;
+    int64_t internal_diff = int64_t{internal_timestamp} - internal_ref_;
     assert(numerator_ > 0);  // Should not be possible.
     // Do not update references in this method.
     // Switch |denominator_| and |numerator_| to convert the other way.
     return external_ref_ + (internal_diff * denominator_) / numerator_;
   }
 }
 
 }  // namespace webrtc