Audio output debug recording.

content/browser/renderer_host/media/audio_debug_file_writer.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 "content/browser/renderer_host/media/audio_debug_file_writer.h"
 
 #include <stdint.h>
 #include <array>
 #include <utility>
 
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #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 {
 
 namespace {
 
 // Windows WAVE format header
 // Byte order: Little-endian
 // Offset Length  Content
 //  0      4     "RIFF"
 //  4      4     <file length - 8>
@@ skipping 30 matching lines @@
  public:
   CharBufferWriter(char* buf, int max_size)
       : buf_(buf), max_size_(max_size), size_(0) {}
 
   void Write(const char* data, int data_size) {
     CHECK_LE(size_ + data_size, max_size_);
     memcpy(&buf_[size_], data, data_size);
     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);
     Write(reinterpret_cast<const char*>(&val), sizeof(val));
   }
 
   void WriteLE32(uint32_t data) {
     uint32_t val = base::ByteSwapToLE32(data);
     Write(reinterpret_cast<const char*>(&val), sizeof(val));
   }
@@ skipping 76 matching lines @@
   void WriteHeader();
 
   void CreateRecordingFile(const base::FilePath& file_name);
 
   // The file to write to.
   base::File file_;
 
   // 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.
   std::unique_ptr<int16_t[]> interleaved_data_;
   int interleaved_data_size_;
 };
 
 // static
 AudioDebugFileWriter::AudioFileWriterUniquePtr
 AudioDebugFileWriter::AudioFileWriter::Create(
     const base::FilePath& file_name,
     const media::AudioParameters& params) {
   AudioFileWriterUniquePtr file_writer(new AudioFileWriter(params));
 
   // base::Unretained is safe, because destructor is called on FILE thread or on
   // FILE message loop destruction.
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&AudioFileWriter::CreateRecordingFile,
                  base::Unretained(file_writer.get()), file_name));
   return file_writer;
 }
 
 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);
   if (file_.IsValid())
     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;
 
   // Convert to 16 bit audio and write to file.
   int data_size = data->frames() * data->channels();
   if (!interleaved_data_ || interleaved_data_size_ < data_size) {
     interleaved_data_.reset(new int16_t[data_size]);
     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),
                 "Only 2 bytes per channel is supported.");
   for (int i = 0; i < data_size; ++i)
     interleaved_data_[i] = base::ByteSwapToLE16(interleaved_data_[i]);
 #endif
 
   file_.WriteAtCurrentPos(reinterpret_cast<char*>(interleaved_data_.get()),
                           data_size * sizeof(interleaved_data_[0]));
@@ skipping 29 matching lines @@
   // fails, so it will continue to post data to be recorded, which won't
   // be written to the file. This also won't be reflected in WillWrite(). It's
   // fine, because this situation is rare, and all the posting is expected to
   // happen in case of success anyways. This allows us to save on thread hops
   // for error reporting and to avoid dealing with lifetime issues. It also
   // means file_.IsValid() should always be checked before issuing writes to it.
   PLOG(ERROR) << "Could not open debug recording file, error="
               << file_.error_details();
 }
 
-AudioDebugFileWriter::AudioDebugFileWriter(
-    const media::AudioParameters& params)
+AudioDebugFileWriter::AudioDebugFileWriter(const media::AudioParameters& params)
     : params_(params) {
   client_sequence_checker_.DetachFromSequence();
 }
 
 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_);
   file_writer_ = AudioFileWriter::Create(file_name, params_);
 }
 
 void AudioDebugFileWriter::Stop() {
   DCHECK(client_sequence_checker_.CalledOnValidSequence());
   // |file_writer_| is deleted on FILE thread.
   file_writer_.reset();
@@ skipping 15 matching lines @@
 
 bool AudioDebugFileWriter::WillWrite() {
   // Note that if this is called from any place other than
   // |client_sequence_checker_| then there is a data race here, but it's fine,
   // because Write() will check for |file_writer_|. So, we are not very precise
   // here, but it's fine: we can afford missing some data or scheduling some
   // no-op writes.
   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