Add sample rates checking in MediaStreamAudioProcessor

content/renderer/media/media_stream_audio_processor.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/media_stream_audio_processor.h"
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/trace_event/trace_event.h"
 #include "content/public/common/content_switches.h"
 #include "content/renderer/media/media_stream_audio_processor_options.h"
 #include "content/renderer/media/rtc_media_constraints.h"
 #include "content/renderer/media/webrtc_audio_device_impl.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_converter.h"
 #include "media/base/audio_fifo.h"
 #include "media/base/channel_layout.h"
+#include "media/base/limits.h"
 #include "third_party/WebKit/public/platform/WebMediaConstraints.h"
 #include "third_party/libjingle/source/talk/app/webrtc/mediaconstraintsinterface.h"
 #include "third_party/webrtc/modules/audio_processing/typing_detection.h"
 
 namespace content {
 
 namespace {
 
 using webrtc::AudioProcessing;
 using webrtc::NoiseSuppression;
@@ skipping 101 matching lines @@
                        int source_frames,
                        int destination_frames,
                        int sample_rate)
      : source_channels_(source_channels),
        source_frames_(source_frames),
        sample_rate_(sample_rate),
        destination_(
            new MediaStreamAudioBus(destination_channels, destination_frames)),
        data_available_(false) {
     DCHECK_GE(source_channels, destination_channels);
-    DCHECK_GT(sample_rate_, 0);
+    DCHECK_GE(sample_rate_, media::limits::kMinSampleRate);

[Henrik Grunell, 2015/09/30 08:19:25]

I was thinking to test the set of explicit samples rates that we support, e.g.
8000, 16000, and so on. However I don't know exactly what we support and if
that's defined somewhere. Deferring to Henrik A to answer that.

[henrika (OOO until Aug 14), 2015/09/30 08:49:18]

Have not done the latest changes in this area and can't say for sure but it
seems like we support "all rates". See
https://code.google.com/p/chromium/codesearch#chromium/src/content/renderer/m...
and\
https://code.google.com/p/chromium/codesearch#chromium/src/media/audio/sample...

+    DCHECK_LE(sample_rate_, media::limits::kMaxSampleRate);
 
     if (source_channels > destination_channels) {
       audio_source_intermediate_ =
           media::AudioBus::CreateWrapper(destination_channels);
     }
 
     if (source_frames != destination_frames) {
       // Since we require every Push to be followed by as many Consumes as
       // possible, twice the larger of the two is a (probably) loose upper bound
       // on the FIFO size.
@@ skipping 527 matching lines @@
   if (echo_information_) {
     echo_information_.get()->UpdateAecDelayStats(ap->echo_cancellation());
   }
 
   // Return 0 if the volume hasn't been changed, and otherwise the new volume.
   return (agc->stream_analog_level() == volume) ?
       0 : agc->stream_analog_level();
 }
 
 }  // namespace content