| // Copyright 2015 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "cobalt/audio/audio_destination_node.h" |
| |
| #include "cobalt/audio/audio_context.h" |
| |
| namespace cobalt { |
| namespace audio { |
| |
| namespace { |
| // An AudioDestinationNode representing the audio hardware end-point (the |
| // normal case) can potentially output more than 2 channels of audio if the |
| // audio hardware is multi-channel. Max channel count is the maximum number of |
| // channels that this hardware is capable of supporting. If this value is 0, |
| // then this indicates that channel count may not be changed. |
| // TODO: Get the actual maximum channel count that can be supported from |
| // hardware. We only support up to two stereo channels for now. |
| const uint32 kMaxChannelCount = 2; |
| } // namespace |
| |
| // numberOfInputs : 1 |
| // numberOfOutputs : 0 |
| AudioDestinationNode::AudioDestinationNode(AudioContext* context) |
| : AudioNode(context), max_channel_count_(kMaxChannelCount) { |
| AudioLock::AutoLock lock(audio_lock()); |
| |
| AddInput(new AudioNodeInput(this)); |
| } |
| |
| AudioDestinationNode::~AudioDestinationNode() { |
| // Clear the audio device before lock to avoid race condition of destroying |
| // AudioDestinationNode and calling FillAudioBus() from the Audio thread. |
| audio_device_.reset(); |
| |
| AudioLock::AutoLock lock(audio_lock()); |
| |
| DCHECK_EQ(number_of_outputs(), 0u); |
| RemoveAllInputs(); |
| } |
| |
| void AudioDestinationNode::OnInputNodeConnected() { |
| audio_lock()->AssertLocked(); |
| |
| if (!audio_device_) { |
| audio_device_.reset( |
| new AudioDevice(static_cast<int>(channel_count(NULL)), this)); |
| } |
| } |
| |
| void AudioDestinationNode::FillAudioBus(ShellAudioBus* audio_bus, |
| bool* silence) { |
| // This is called by Audio thread. |
| AudioLock::AutoLock lock(audio_lock()); |
| |
| // Destination node only has one input. |
| DCHECK_EQ(number_of_inputs(), 1u); |
| Input(0)->FillAudioBus(audio_bus, silence); |
| } |
| |
| } // namespace audio |
| } // namespace cobalt |