AudioDecoder: New method SampleRateHz, + implementations for our codecs

webrtc/modules/audio_coding/codecs/builtin_audio_decoder_factory.cc

 /*
  *  Copyright (c) 2016 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.
  */
 
@@ skipping 56 matching lines @@
      [](const SdpAudioFormat& format) {
        return format.clockrate_hz == 8000 && format.num_channels == 1
                   ? Unique(new AudioDecoderIlbc)
                   : nullptr;
      }},
 #endif
 #if defined(WEBRTC_CODEC_ISACFX)
     {"isac",
      [](const SdpAudioFormat& format) {
        return format.clockrate_hz == 16000 && format.num_channels == 1
-                  ? Unique(new AudioDecoderIsacFix)
+                  ? Unique(new AudioDecoderIsacFix(format.clockrate_hz))
                   : nullptr;
      }},
 #elif defined(WEBRTC_CODEC_ISAC)
     {"isac",
      [](const SdpAudioFormat& format) {
        return (format.clockrate_hz == 16000 || format.clockrate_hz == 32000) &&
                       format.num_channels == 1
-                  ? Unique(new AudioDecoderIsac)
+                  ? Unique(new AudioDecoderIsac(format.clockrate_hz))
                   : nullptr;
      }},
 #endif
     {"l16",
      [](const SdpAudioFormat& format) {
        return format.num_channels >= 1
-                  ? Unique(new AudioDecoderPcm16B(format.num_channels))
+                  ? Unique(new AudioDecoderPcm16B(format.clockrate_hz,
+                                                  format.num_channels))
                   : nullptr;
      }},
 #ifdef WEBRTC_CODEC_G722
     {"g722",
      [](const SdpAudioFormat& format) {
        if (format.clockrate_hz == 8000) {
          if (format.num_channels == 1)
            return Unique(new AudioDecoderG722);
          if (format.num_channels == 2)
            return Unique(new AudioDecoderG722Stereo);
@@ skipping 26 matching lines @@
 class BuiltinAudioDecoderFactory : public AudioDecoderFactory {
  public:
   std::vector<SdpAudioFormat> GetSupportedFormats() override {
     FATAL() << "Not implemented yet!";
   }
 
   std::unique_ptr<AudioDecoder> MakeAudioDecoder(
       const SdpAudioFormat& format) override {
     for (const auto& dc : decoder_constructors) {
       if (STR_CASE_CMP(format.name.c_str(), dc.name) == 0) {
-        return std::unique_ptr<AudioDecoder>(dc.constructor(format));
+        std::unique_ptr<AudioDecoder> dec = dc.constructor(format);
+        if (dec) {
+          const int expected_sample_rate_hz =
+              STR_CASE_CMP(format.name.c_str(), "g722") == 0
+                  ? 2 * format.clockrate_hz
+                  : format.clockrate_hz;
+          RTC_CHECK_EQ(expected_sample_rate_hz, dec->SampleRateHz());
+        }
+        return dec;
       }
     }
     return nullptr;
   }
 };
 
 }  // namespace
 
 rtc::scoped_refptr<AudioDecoderFactory> CreateBuiltinAudioDecoderFactory() {
   return rtc::scoped_refptr<AudioDecoderFactory>(
       new rtc::RefCountedObject<BuiltinAudioDecoderFactory>);
 }
 
 }  // namespace webrtc