Mute audio when volume is zero on Android.

media/audio/android/opensles_output.cc

 // Copyright (c) 2012 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 "media/audio/android/opensles_output.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "media/audio/android/audio_manager_android.h"
 
@@ skipping 10 matching lines @@
 
 OpenSLESOutputStream::OpenSLESOutputStream(AudioManagerAndroid* manager,
                                            const AudioParameters& params)
     : audio_manager_(manager),
       callback_(NULL),
       player_(NULL),
       simple_buffer_queue_(NULL),
       active_buffer_index_(0),
       buffer_size_bytes_(0),
       started_(false),
+      muted_(false),
       volume_(1.0) {
   DVLOG(2) << "OpenSLESOutputStream::OpenSLESOutputStream()";
   format_.formatType = SL_DATAFORMAT_PCM;
   format_.numChannels = static_cast<SLuint32>(params.channels());
   // Provides sampling rate in milliHertz to OpenSLES.
   format_.samplesPerSec = static_cast<SLuint32>(params.sample_rate() * 1000);
   format_.bitsPerSample = params.bits_per_sample();
   format_.containerSize = params.bits_per_sample();
   format_.endianness = SL_BYTEORDER_LITTLEENDIAN;
   if (format_.numChannels == 1)
@@ skipping 124 matching lines @@
     return;
   }
   volume_ = volume_float;
 }
 
 void OpenSLESOutputStream::GetVolume(double* volume) {
   DCHECK(thread_checker_.CalledOnValidThread());
   *volume = static_cast<double>(volume_);
 }
 
+void OpenSLESOutputStream::SetMute(bool muted) {
+  DVLOG(2) << "OpenSLESOutputStream::SetMute(" << muted << ")";
+  DCHECK(thread_checker_.CalledOnValidThread());
+  muted_ = muted;
+}
+
 bool OpenSLESOutputStream::CreatePlayer() {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!engine_object_.Get());
   DCHECK(!player_object_.Get());
   DCHECK(!output_mixer_.Get());
   DCHECK(!player_);
   DCHECK(!simple_buffer_queue_);
 
   // Initializes the engine object with specific option. After working with the
   // object, we need to free the object and its resources.
@@ skipping 132 matching lines @@
   int frames_filled = callback_->OnMoreData(
       audio_bus_.get(), AudioBuffersState(0, hardware_delay));
   if (frames_filled <= 0) {
     // Audio source is shutting down, or halted on error.
     return;
   }
 
   // Note: If the internal representation ever changes from 16-bit PCM to
   // raw float, the data must be clipped and sanitized since it may come
   // from an untrusted source such as NaCl.
-  audio_bus_->Scale(volume_);
+  audio_bus_->Scale(muted_ ? 0.0f : volume_);
   audio_bus_->ToInterleaved(frames_filled,
                             format_.bitsPerSample / 8,
                             audio_data_[active_buffer_index_]);
 
   const int num_filled_bytes =
       frames_filled * audio_bus_->channels() * format_.bitsPerSample / 8;
   DCHECK_LE(static_cast<size_t>(num_filled_bytes), buffer_size_bytes_);
 
   // Enqueue the buffer for playback.
   SLresult err =
@@ skipping 24 matching lines @@
   }
 }
 
 void OpenSLESOutputStream::HandleError(SLresult error) {
   DLOG(ERROR) << "OpenSLES Output error " << error;
   if (callback_)
     callback_->OnError(this);
 }
 
 }  // namespace media