Add vector_math::FMUL. Replace audio_util::AdjustVolume.

media/base/audio_bus.cc

 // Copyright (c) 2012 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 "media/base/audio_bus.h"
 
 #include <limits>
 
 #include "base/logging.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/limits.h"
+#include "media/base/vector_math.h"
 
 namespace media {
 
 static bool IsAligned(void* ptr) {
   return (reinterpret_cast<uintptr_t>(ptr) &
           (AudioBus::kChannelAlignment - 1)) == 0U;
 }
 
 // Calculates the required size for an AudioBus with the given params, sets
 // |aligned_frames| to the actual frame length of each channel array.
@@ skipping 278 matching lines @@
 void AudioBus::CopyTo(AudioBus* dest) const {
   CHECK_EQ(channels(), dest->channels());
   CHECK_EQ(frames(), dest->frames());
 
   // Since we don't know if the other AudioBus is wrapped or not (and we don't
   // want to care), just copy using the public channel() accessors.
   for (int i = 0; i < channels(); ++i)
     memcpy(dest->channel(i), channel(i), sizeof(*channel(i)) * frames());
 }
 
+void AudioBus::Scale(float volume) {
+  if (volume > 0 && volume != 1) {
+    for (int i = 0; i < channels(); ++i)
+      vector_math::FMUL(channel(i), volume, frames(), channel(i));
+  } else if (volume == 0) {
+    Zero();
+  }
+}
+
 }  // namespace media