Exposes a shlib interface for media/audio path.

chromecast/media/audio/cast_audio_manager.cc

+// Copyright 2015 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 "chromecast/media/audio/cast_audio_manager.h"
+
+#include "base/logging.h"
+#include "chromecast/base/task_runner_impl.h"
+#include "chromecast/media/audio/chromecast_device_audio_output_stream.h"
+#include "chromecast/media/base/converters.h"
+#include "chromecast/public/cast_audio_output_device.h"
+#include "chromecast/public/cast_audio_output_stream.h"
+
+namespace chromecast {
+namespace media {
+
+namespace {
+
+// Default parameters to provide for input stream.
+const int kDefaultBitsPerSample = 16;
+const int kDefaultInputBufferSize = 1024;
+const int kDefaultSampleRate = 32000;
+
+}  // namespace
+
+CastAudioManager::CastAudioManager(::media::AudioLogFactory* audio_log_factory,
+                                   CastAudioOutputDevice* output_device)
+    : ::media::AudioManagerBase(audio_log_factory),
+      audio_output_device_(output_device) {
+  CHECK(audio_output_device_);
+  SetMaxOutputStreamsAllowed(
+      audio_output_device_->GetMaximumOutputStreamsAllowed());
+}
+
+CastAudioManager::~CastAudioManager() {
+  Shutdown();
+}
+
+bool CastAudioManager::HasAudioOutputDevices() {
+  return true;
+}
+
+bool CastAudioManager::HasAudioInputDevices() {
+  return false;
+}
+
+void CastAudioManager::ShowAudioInputSettings() {
+  LOG(WARNING) << "No support for input audio devices.";
+}
+
+void CastAudioManager::GetAudioInputDeviceNames(
+    ::media::AudioDeviceNames* device_names) {
+  LOG(WARNING) << "No support for input audio devices.";
+}
+
+::media::AudioParameters CastAudioManager::GetInputStreamParameters(
+    const std::string& device_id) {
+  // TODO(slan): Providing the invalid parameters impacts also the output
+  // parameter selection during WebAudio playback (and it fails). (b/20630187).
+  LOG(WARNING) << "No support for input audio devices.";
+  return ::media::AudioParameters(
+      ::media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
+      ::media::CHANNEL_LAYOUT_STEREO,
+      kDefaultSampleRate,
+      kDefaultBitsPerSample,
+      kDefaultInputBufferSize);
+}
+
+::media::AudioInputStream* CastAudioManager::MakeLinearInputStream(
+    const ::media::AudioParameters& params,
+    const std::string& device_id) {
+  LOG(WARNING) << "No support for input audio devices";
+  return nullptr;
+}
+
+::media::AudioInputStream* CastAudioManager::MakeLowLatencyInputStream(
+    const ::media::AudioParameters& params,
+    const std::string& device_id) {
+  LOG(WARNING) << "No support for input audio devices";
+  return nullptr;
+}
+
+::media::AudioOutputStream* CastAudioManager::MakeLinearOutputStream(
+    const ::media::AudioParameters& params) {
+  DCHECK_EQ(::media::AudioParameters::AUDIO_PCM_LINEAR, params.format());
+  return MakeCastOutputStream(params);
+}
+
+::media::AudioOutputStream* CastAudioManager::MakeLowLatencyOutputStream(
+    const ::media::AudioParameters& params,
+    const std::string& device_id) {
+  DCHECK_EQ(::media::AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
+  return MakeCastOutputStream(params);
+}
+
+::media::AudioParameters CastAudioManager::GetPreferredOutputStreamParameters(
+    const std::string& output_device_id,
+    const ::media::AudioParameters& suggested) {
+  // Convert the suggested params into the chromecast variety.
+  AudioParameters params = FromChromiumParams(suggested);
+
+  // Get the preferences. Convert them back to Chromium params and return.
+  params = audio_output_device_->GetPreferredOutputStreamParameters(params);
+  return FromChromecastParams(params);
+}
+
+::media::AudioOutputStream* CastAudioManager::MakeCastOutputStream(
+    const ::media::AudioParameters& params) {
+  // Get the Cast output stream.
+  AudioParameters chromecast_params = FromChromiumParams(params);
+  CastAudioOutputStream* stream = audio_output_device_->MakeOutputStream(
+      chromecast_params, new chromecast::TaskRunnerImpl());

[halliwell, 2015/07/29 15:06:57]

nit: chromecast:: unnecessary.

[slan, 2015/07/29 19:51:55]

Removed.

+  if (!stream)
+    return nullptr;
+
+  // Note: The caller of this method does not own the returned instance of the
+  // stream. The stream MUST call AudioManagerBase::ReleaseOutputStream() as
+  // the last line of its Close() method to avoid a leak. This pattern is not
+  // favorable, but is currently required by AudioManagerBase. Please see
+  // ChromecastDeviceAudioOutputStream::Close() before changing this behavior.
+  return new ChromecastDeviceAudioOutputStream(stream, chromecast_params, this);
+}
+
+}  // namespace media
+}  // namespace chromecast