1/*
2 *  Copyright (c) 2013 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_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
12#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
13
14#include <string>
15
16#include "webrtc/base/constructormagic.h"
17#include "webrtc/system_wrappers/interface/scoped_ptr.h"
18#include "webrtc/typedefs.h"
19
20namespace webrtc {
21namespace test {
22
23// Class serving as an infinite source of audio, realized by looping an audio
24// clip.
25class AudioLoop {
26 public:
27  AudioLoop()
28      : next_index_(0),
29        loop_length_samples_(0),
30        block_length_samples_(0) {
31  }
32
33  virtual ~AudioLoop() {}
34
35  // Initializes the AudioLoop by reading from |file_name|. The loop will be no
36  // longer than |max_loop_length_samples|, if the length of the file is
37  // greater. Otherwise, the loop length is the same as the file length.
38  // The audio will be delivered in blocks of |block_length_samples|.
39  // Returns false if the initialization failed, otherwise true.
40  bool Init(const std::string file_name, size_t max_loop_length_samples,
41            size_t block_length_samples);
42
43  // Returns a pointer to the next block of audio. The number given as
44  // |block_length_samples| to the Init() function determines how many samples
45  // that can be safely read from the pointer.
46  const int16_t* GetNextBlock();
47
48 private:
49  size_t next_index_;
50  size_t loop_length_samples_;
51  size_t block_length_samples_;
52  scoped_ptr<int16_t[]> audio_array_;
53
54  DISALLOW_COPY_AND_ASSIGN(AudioLoop);
55};
56
57}  // namespace test
58}  // namespace webrtc
59#endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
60