• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_
12 #define WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_
13 
14 #include "webrtc/typedefs.h"
15 
16 namespace webrtc {
17 
18 class AudioFrame;
19 
20 // TODO(andrew): consolidate this with utility.h and audio_frame_manipulator.h.
21 // Change reference parameters to pointers. Consider using a namespace rather
22 // than a class.
23 class AudioFrameOperations {
24  public:
25   // Upmixes mono |src_audio| to stereo |dst_audio|. This is an out-of-place
26   // operation, meaning src_audio and dst_audio must point to different
27   // buffers. It is the caller's responsibility to ensure that |dst_audio| is
28   // sufficiently large.
29   static void MonoToStereo(const int16_t* src_audio, size_t samples_per_channel,
30                            int16_t* dst_audio);
31   // |frame.num_channels_| will be updated. This version checks for sufficient
32   // buffer size and that |num_channels_| is mono.
33   static int MonoToStereo(AudioFrame* frame);
34 
35   // Downmixes stereo |src_audio| to mono |dst_audio|. This is an in-place
36   // operation, meaning |src_audio| and |dst_audio| may point to the same
37   // buffer.
38   static void StereoToMono(const int16_t* src_audio, size_t samples_per_channel,
39                            int16_t* dst_audio);
40   // |frame.num_channels_| will be updated. This version checks that
41   // |num_channels_| is stereo.
42   static int StereoToMono(AudioFrame* frame);
43 
44   // Swap the left and right channels of |frame|. Fails silently if |frame| is
45   // not stereo.
46   static void SwapStereoChannels(AudioFrame* frame);
47 
48   // Zeros out the audio and sets |frame.energy| to zero.
49   static void Mute(AudioFrame& frame);
50 
51   static int Scale(float left, float right, AudioFrame& frame);
52 
53   static int ScaleWithSat(float scale, AudioFrame& frame);
54 };
55 
56 }  // namespace webrtc
57 
58 #endif  // #ifndef WEBRTC_MODULES_UTILITY_INCLUDE_AUDIO_FRAME_OPERATIONS_H_
59