AudioController accepts hardware buffer size as parameter.

BUG=39885
TEST=media_unitests
AudioController to take hardware buffer size for opening the audio device.

Review URL: http://codereview.chromium.org/2822014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@50046 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 51 insertions, 22 deletions

diff --git a/media/audio/audio_controller.cc b/media/audio/audio_controller.cc
index 8e9357b..b30f722 100644
--- a/media/audio/audio_controller.cc
+++ b/media/audio/audio_controller.cc
@@ -4,16 +4,10 @@
 
 #include "media/audio/audio_controller.h"
 
-// This constant governs the hardware audio buffer size, this value should be
-// choosen carefully and is platform specific.
-static const int kSamplesPerHardwarePacket = 8192;
-
-static const uint32 kMegabytes = 1024 * 1024;
-
 // The following parameters limit the request buffer and packet size from the
 // renderer to avoid renderer from requesting too much memory.
-static const uint32 kMaxDecodedPacketSize = 2 * kMegabytes;
-static const uint32 kMaxBufferCapacity = 5 * kMegabytes;
+static const int kMegabytes = 1024 * 1024;
+static const int kMaxHardwareBufferSize = 2 * kMegabytes;
 static const int kMaxChannels = 32;
 static const int kMaxBitsPerSample = 64;
 static const int kMaxSampleRate = 192000;
@@ -21,13 +15,17 @@ static const int kMaxSampleRate = 192000;
 // Return true if the parameters for creating an audio stream is valid.
 // Return false otherwise.
 static bool CheckParameters(int channels, int sample_rate,
-                            int bits_per_sample) {
+                            int bits_per_sample, int hardware_buffer_size) {
   if (channels <= 0 || channels > kMaxChannels)
     return false;
   if (sample_rate <= 0 || sample_rate > kMaxSampleRate)
     return false;
   if (bits_per_sample <= 0 || bits_per_sample > kMaxBitsPerSample)
     return false;
+  if (hardware_buffer_size <= 0 ||
+      hardware_buffer_size > kMaxHardwareBufferSize) {
+    return false;
+  }
   return true;
 }
 
@@ -54,9 +52,11 @@ scoped_refptr<AudioController> AudioController::Create(
     int channels,
     int sample_rate,
     int bits_per_sample,
+    int hardware_buffer_size,
     uint32 buffer_capacity) {
 
-  if (!CheckParameters(channels, sample_rate, bits_per_sample))
+  if (!CheckParameters(channels, sample_rate, bits_per_sample,
+                       hardware_buffer_size))
     return NULL;
 
   // Starts the audio controller thread.
@@ -69,7 +69,8 @@ scoped_refptr<AudioController> AudioController::Create(
   source->thread_.message_loop()->PostTask(
       FROM_HERE,
       NewRunnableMethod(source.get(), &AudioController::DoCreate,
-                        format, channels, sample_rate, bits_per_sample));
+                        format, channels, sample_rate, bits_per_sample,
+                        hardware_buffer_size));
   return source;
 }
 
@@ -80,11 +81,13 @@ scoped_refptr<AudioController> AudioController::CreateLowLatency(
     int channels,
     int sample_rate,
     int bits_per_sample,
+    int hardware_buffer_size,
     SyncReader* sync_reader) {
 
   DCHECK(sync_reader);
 
-  if (!CheckParameters(channels, sample_rate, bits_per_sample))
+  if (!CheckParameters(channels, sample_rate, bits_per_sample,
+                       hardware_buffer_size))
     return NULL;
 
   // Starts the audio controller thread.
@@ -97,7 +100,8 @@ scoped_refptr<AudioController> AudioController::CreateLowLatency(
   source->thread_.message_loop()->PostTask(
       FROM_HERE,
       NewRunnableMethod(source.get(), &AudioController::DoCreate,
-                        format, channels, sample_rate, bits_per_sample));
+                        format, channels, sample_rate, bits_per_sample,
+                        hardware_buffer_size));
   return source;
 }
 
@@ -145,7 +149,8 @@ void AudioController::EnqueueData(const uint8* data, uint32 size) {
 }
 
 void AudioController::DoCreate(AudioManager::Format format, int channels,
-                               int sample_rate, int bits_per_sample) {
+                               int sample_rate, int bits_per_sample,
+                               int hardware_buffer_size) {
   // Create the stream in the first place.
   stream_ = AudioManager::GetAudioManager()->MakeAudioStream(
       format, channels, sample_rate, bits_per_sample);
@@ -156,9 +161,7 @@ void AudioController::DoCreate(AudioManager::Format format, int channels,
     return;
   }
 
-  uint32 hardware_packet_size = kSamplesPerHardwarePacket * channels *
-      bits_per_sample / 8;
-  if (stream_ && !stream_->Open(hardware_packet_size)) {
+  if (stream_ && !stream_->Open(hardware_buffer_size)) {
     stream_->Close();
     stream_ = NULL;
 
diff --git a/media/audio/audio_controller.h b/media/audio/audio_controller.h
index dae3d58..21d6d22 100644
--- a/media/audio/audio_controller.h
+++ b/media/audio/audio_controller.h
@@ -107,6 +107,7 @@ class AudioController : public base::RefCountedThreadSafe<AudioController>,
       int channels,                   // Number of channels.
       int sample_rate,                // Sampling frequency/rate.
       int bits_per_sample,            // Number of bits per sample.
+      int hardware_buffer_size,       // Size of the hardware buffer.
 
       // Soft limit for buffer capacity in this controller. This parameter
       // is used only in regular latency mode.
@@ -119,6 +120,7 @@ class AudioController : public base::RefCountedThreadSafe<AudioController>,
       int channels,                   // Number of channels.
       int sample_rate,                // Sampling frequency/rate.
       int bits_per_sample,            // Number of bits per sample.
+      int hardware_buffer_size,       // Size of the hardware buffer.
 
       // External synchronous reader for audio controller.
       SyncReader* sync_reader);
@@ -161,7 +163,8 @@ class AudioController : public base::RefCountedThreadSafe<AudioController>,
 
   // The following methods are executed on the audio controller thread.
   void DoCreate(AudioManager::Format format, int channels,
-                int sample_rate, int bits_per_sample);
+                int sample_rate, int bits_per_sample,
+                int hardware_buffer_size);
   void DoPlay();
   void DoPause();
   void DoFlush();
diff --git a/media/audio/audio_controller_unittest.cc b/media/audio/audio_controller_unittest.cc
index 5c5a522..c2a30ae 100644
--- a/media/audio/audio_controller_unittest.cc
+++ b/media/audio/audio_controller_unittest.cc
@@ -15,6 +15,13 @@ using ::testing::Exactly;
 using ::testing::InvokeWithoutArgs;
 using ::testing::NotNull;
 
+static const int kSampleRate = AudioManager::kAudioCDSampleRate;
+static const int kBitsPerSample = 16;
+static const int kChannels = 2;
+static const int kHardwareBufferSize = kSampleRate * kBitsPerSample *
+                                       kChannels / 8;
+static const int kBufferCapacity = 3 * kHardwareBufferSize;
+
 namespace media {
 
 class MockAudioControllerEventHandler : public AudioController::EventHandler {
@@ -86,8 +93,8 @@ TEST(AudioControllerTest, PlayAndClose) {
       .WillRepeatedly(SignalEvent(&event, &count, 10));
 
   scoped_refptr<AudioController> controller = AudioController::Create(
-      &event_handler, AudioManager::AUDIO_PCM_LINEAR, 1,
-      AudioManager::kAudioCDSampleRate, 16, 4096);
+      &event_handler, AudioManager::AUDIO_PCM_LINEAR, kChannels,
+      kSampleRate, kBitsPerSample, kHardwareBufferSize, kBufferCapacity);
   ASSERT_TRUE(controller.get());
 
   // Wait for OnCreated() to be called.
@@ -135,8 +142,8 @@ TEST(AudioControllerTest, PlayPauseClose) {
       .WillOnce(InvokeWithoutArgs(&event, &base::WaitableEvent::Signal));
 
   scoped_refptr<AudioController> controller = AudioController::Create(
-      &event_handler, AudioManager::AUDIO_PCM_LINEAR, 1,
-      AudioManager::kAudioCDSampleRate, 16, 4096);
+      &event_handler, AudioManager::AUDIO_PCM_LINEAR, kChannels,
+      kSampleRate, kBitsPerSample, kHardwareBufferSize, kBufferCapacity);
   ASSERT_TRUE(controller.get());
 
   // Wait for OnCreated() to be called.
@@ -161,4 +168,20 @@ TEST(AudioControllerTest, PlayPauseClose) {
   controller = NULL;
 }
 
+TEST(AudioControllerTest, HardwareBufferTooLarge) {
+  if (!HasAudioDevices() || IsRunningHeadless())
+    return;
+
+  // Create an audio device with a very large hardware buffer size.
+  MockAudioControllerEventHandler event_handler;
+  scoped_refptr<AudioController> controller = AudioController::Create(
+      &event_handler, AudioManager::AUDIO_PCM_LINEAR, kChannels,
+      kSampleRate, kBitsPerSample, kHardwareBufferSize * 1000,
+      kBufferCapacity);
+
+  // Use assert because we don't stop the device and assume we can't
+  // create one.
+  ASSERT_FALSE(controller);
+}
+
 }  // namespace media