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_AUDIO_CODING_NETEQ_RANDOM_VECTOR_H_
12#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_RANDOM_VECTOR_H_
13
14#include <string.h>  // size_t
15
16#include "webrtc/base/constructormagic.h"
17#include "webrtc/typedefs.h"
18
19namespace webrtc {
20
21// This class generates pseudo-random samples.
22class RandomVector {
23 public:
24  static const int kRandomTableSize = 256;
25  static const int16_t kRandomTable[kRandomTableSize];
26
27  RandomVector()
28      : seed_(777),
29        seed_increment_(1) {
30  }
31
32  void Reset();
33
34  void Generate(size_t length, int16_t* output);
35
36  void IncreaseSeedIncrement(int16_t increase_by);
37
38  // Accessors and mutators.
39  int16_t seed_increment() { return seed_increment_; }
40  void set_seed_increment(int16_t value) { seed_increment_ = value; }
41
42 private:
43  uint32_t seed_;
44  int16_t seed_increment_;
45
46  DISALLOW_COPY_AND_ASSIGN(RandomVector);
47};
48
49}  // namespace webrtc
50#endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_RANDOM_VECTOR_H_
51