1 files changed, 58 insertions, 0 deletions
diff --git a/webrtc/modules/utility/include/audio_frame_operations.h b/webrtc/modules/utility/include/audio_frame_operations.h
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+++ b/webrtc/modules/utility/include/audio_frame_operations.h
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+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_
+#define WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_
+
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+class AudioFrame;
+
+// TODO(andrew): consolidate this with utility.h and audio_frame_manipulator.h.
+// Change reference parameters to pointers. Consider using a namespace rather
+// than a class.
+class AudioFrameOperations {
+ public:
+  // Upmixes mono |src_audio| to stereo |dst_audio|. This is an out-of-place
+  // operation, meaning src_audio and dst_audio must point to different
+  // buffers. It is the caller's responsibility to ensure that |dst_audio| is
+  // sufficiently large.
+  static void MonoToStereo(const int16_t* src_audio, size_t samples_per_channel,
+                           int16_t* dst_audio);
+  // |frame.num_channels_| will be updated. This version checks for sufficient
+  // buffer size and that |num_channels_| is mono.
+  static int MonoToStereo(AudioFrame* frame);
+
+  // Downmixes stereo |src_audio| to mono |dst_audio|. This is an in-place
+  // operation, meaning |src_audio| and |dst_audio| may point to the same
+  // buffer.
+  static void StereoToMono(const int16_t* src_audio, size_t samples_per_channel,
+                           int16_t* dst_audio);
+  // |frame.num_channels_| will be updated. This version checks that
+  // |num_channels_| is stereo.
+  static int StereoToMono(AudioFrame* frame);
+
+  // Swap the left and right channels of |frame|. Fails silently if |frame| is
+  // not stereo.
+  static void SwapStereoChannels(AudioFrame* frame);
+
+  // Zeros out the audio and sets |frame.energy| to zero.
+  static void Mute(AudioFrame& frame);
+
+  static int Scale(float left, float right, AudioFrame& frame);
+
+  static int ScaleWithSat(float scale, AudioFrame& frame);
+};
+
+}  // namespace webrtc
+
+#endif  // #ifndef WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_