Audio output debug recording.

content/browser/renderer_host/media/audio_debug_file_writer.cc

Index: content/browser/renderer_host/media/audio_debug_file_writer.cc
diff --git a/content/browser/renderer_host/media/audio_debug_file_writer.cc b/content/browser/renderer_host/media/audio_debug_file_writer.cc
index 1656a1cca232a2d020da4a5df59f96eb597bafdf..f4b262461a8e829fa63e042c353d04cb886736cf 100644
--- a/content/browser/renderer_host/media/audio_debug_file_writer.cc
+++ b/content/browser/renderer_host/media/audio_debug_file_writer.cc
@@ -13,6 +13,7 @@
 #include "base/sys_byteorder.h"
 #include "content/public/browser/browser_thread.h"
 #include "media/base/audio_bus.h"
+#include "media/base/audio_sample_types.h"
 
 namespace content {
 
@@ -63,7 +64,9 @@ class CharBufferWriter {
     size_ += data_size;
   }
 
-  void Write(const char(&data)[4]) { Write(static_cast<const char*>(data), 4); }
+  void Write(const char (&data)[4]) {
+    Write(static_cast<const char*>(data), 4);
+  }
 
   void WriteLE16(uint16_t data) {
     uint16_t val = base::ByteSwapToLE16(data);
@@ -160,7 +163,8 @@ class AudioDebugFileWriter::AudioFileWriter {
   // Number of written samples.
   uint64_t samples_;
 
-  // Input audio parameters required to build wave header.
+  // Audio parameters required to build wave header. Number of channels and
+  // sample rate are used.
   const media::AudioParameters params_;
 
   // Intermediate buffer to be written to file. Interleaved 16 bit audio data.
@@ -186,9 +190,7 @@ AudioDebugFileWriter::AudioFileWriter::Create(
 
 AudioDebugFileWriter::AudioFileWriter::AudioFileWriter(
     const media::AudioParameters& params)
-    : samples_(0), params_(params), interleaved_data_size_(0) {
-  DCHECK_EQ(params.bits_per_sample(), kBytesPerSample * 8);
-}
+    : samples_(0), params_(params), interleaved_data_size_(0) {}
 
 AudioDebugFileWriter::AudioFileWriter::~AudioFileWriter() {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
@@ -196,9 +198,9 @@ AudioDebugFileWriter::AudioFileWriter::~AudioFileWriter() {
     WriteHeader();
 }
 
-void AudioDebugFileWriter::AudioFileWriter::Write(
-    const media::AudioBus* data) {
+void AudioDebugFileWriter::AudioFileWriter::Write(const media::AudioBus* data) {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK_EQ(params_.channels(), data->channels());
   if (!file_.IsValid())
     return;
 
@@ -209,8 +211,8 @@ void AudioDebugFileWriter::AudioFileWriter::Write(
     interleaved_data_size_ = data_size;
   }
   samples_ += data_size;
-  data->ToInterleaved(data->frames(), sizeof(interleaved_data_[0]),
-                      interleaved_data_.get());
+  data->ToInterleaved<media::SignedInt16SampleTypeTraits>(
+      data->frames(), interleaved_data_.get());
 
 #ifndef ARCH_CPU_LITTLE_ENDIAN
   static_assert(sizeof(interleaved_data_[0]) == sizeof(uint16_t),
@@ -260,8 +262,7 @@ void AudioDebugFileWriter::AudioFileWriter::CreateRecordingFile(
               << file_.error_details();
 }
 
-AudioDebugFileWriter::AudioDebugFileWriter(
-    const media::AudioParameters& params)
+AudioDebugFileWriter::AudioDebugFileWriter(const media::AudioParameters& params)
     : params_(params) {
   client_sequence_checker_.DetachFromSequence();
 }
@@ -270,6 +271,12 @@ AudioDebugFileWriter::~AudioDebugFileWriter() {
   // |file_writer_| will be deleted on FILE thread.
 }
 
+// static
+std::unique_ptr<media::AudioFileWriter> AudioDebugFileWriter::Create(
+    const media::AudioParameters& params) {
+  return base::MakeUnique<AudioDebugFileWriter>(params);
+}
+
 void AudioDebugFileWriter::Start(const base::FilePath& file_name) {
   DCHECK(client_sequence_checker_.CalledOnValidSequence());
   DCHECK(!file_writer_);
@@ -305,4 +312,8 @@ bool AudioDebugFileWriter::WillWrite() {
   return !!file_writer_;
 }
 
+std::string AudioDebugFileWriter::GetExtension() {

[o1ka, 2017/02/09 13:04:02]

const std::string& maybe? Do you anticipate any usecase what const ref wouldn't
be enough?

[Henrik Grunell, 2017/02/10 09:00:56]

That would be fine, but the constant string would need to be stored as an
std::string member too, which is unnecessary. I changed it to const char* though
(same as for e.g. AudioManager::GetName()). We may not get rid of the extra
copy; I'm not familiar with details of BasicStringPieceType which is the
argument of FilePath::AddExtension(). I think that's anyway better than
increasing the memory usage.

+  return "wav";
+}
+
 }  // namspace content