xref: /aosp_15_r20/external/webrtc/modules/audio_coding/neteq/tools/audio_loop.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
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 MODULES_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
12 #define MODULES_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
13 
14 #include <memory>
15 #include <string>
16 
17 #include "absl/strings/string_view.h"
18 #include "api/array_view.h"
19 
20 namespace webrtc {
21 namespace test {
22 
23 // Class serving as an infinite source of audio, realized by looping an audio
24 // clip.
25 class AudioLoop {
26  public:
AudioLoop()27   AudioLoop()
28       : next_index_(0), loop_length_samples_(0), block_length_samples_(0) {}
29 
~AudioLoop()30   virtual ~AudioLoop() {}
31 
32   AudioLoop(const AudioLoop&) = delete;
33   AudioLoop& operator=(const AudioLoop&) = delete;
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(absl::string_view file_name,
41             size_t max_loop_length_samples,
42             size_t block_length_samples);
43 
44   // Returns a (pointer,size) pair for the next block of audio. The size is
45   // equal to the `block_length_samples` Init() argument.
46   rtc::ArrayView<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   std::unique_ptr<int16_t[]> audio_array_;
53 };
54 
55 }  // namespace test
56 }  // namespace webrtc
57 #endif  // MODULES_AUDIO_CODING_NETEQ_TOOLS_AUDIO_LOOP_H_
58