1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
4 * You can obtain one at http://mozilla.org/MPL/2.0/. */
5
6 #include "AudioMixer.h"
7 #include "gtest/gtest.h"
8
9 using mozilla::AudioDataValue;
10 using mozilla::AudioSampleFormat;
11
12 namespace audio_mixer {
13
14 struct MixerConsumer : public mozilla::MixerCallbackReceiver {
15 /* In this test, the different audio stream and channels are always created to
16 * cancel each other. */
MixerCallbackaudio_mixer::MixerConsumer17 void MixerCallback(AudioDataValue* aData, AudioSampleFormat aFormat,
18 uint32_t aChannels, uint32_t aFrames,
19 uint32_t aSampleRate) {
20 bool silent = true;
21 for (uint32_t i = 0; i < aChannels * aFrames; i++) {
22 if (aData[i] != 0.0) {
23 if (aFormat == mozilla::AUDIO_FORMAT_S16) {
24 fprintf(stderr, "Sample at %d is not silent: %d\n", i,
25 (short)aData[i]);
26 } else {
27 fprintf(stderr, "Sample at %d is not silent: %f\n", i,
28 (float)aData[i]);
29 }
30 silent = false;
31 }
32 }
33 ASSERT_TRUE(silent);
34 }
35 };
36
37 /* Helper function to give us the maximum and minimum value that don't clip,
38 * for a given sample format (integer or floating-point). */
39 template <typename T>
40 T GetLowValue();
41
42 template <typename T>
43 T GetHighValue();
44
45 template <>
GetLowValue()46 float GetLowValue<float>() {
47 return -1.0;
48 }
49
50 template <>
GetLowValue()51 short GetLowValue<short>() {
52 return -INT16_MAX;
53 }
54
55 template <>
GetHighValue()56 float GetHighValue<float>() {
57 return 1.0;
58 }
59
60 template <>
GetHighValue()61 short GetHighValue<short>() {
62 return INT16_MAX;
63 }
64
FillBuffer(AudioDataValue * aBuffer,uint32_t aLength,AudioDataValue aValue)65 void FillBuffer(AudioDataValue* aBuffer, uint32_t aLength,
66 AudioDataValue aValue) {
67 AudioDataValue* end = aBuffer + aLength;
68 while (aBuffer != end) {
69 *aBuffer++ = aValue;
70 }
71 }
72
TEST(AudioMixer,Test)73 TEST(AudioMixer, Test)
74 {
75 const uint32_t CHANNEL_LENGTH = 256;
76 const uint32_t AUDIO_RATE = 44100;
77 MixerConsumer consumer;
78 AudioDataValue a[CHANNEL_LENGTH * 2];
79 AudioDataValue b[CHANNEL_LENGTH * 2];
80 FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
81 FillBuffer(a + CHANNEL_LENGTH, CHANNEL_LENGTH,
82 GetHighValue<AudioDataValue>());
83 FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
84 FillBuffer(b + CHANNEL_LENGTH, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
85
86 {
87 int iterations = 2;
88 mozilla::AudioMixer mixer;
89 mixer.AddCallback(WrapNotNull(&consumer));
90
91 fprintf(stderr, "Test AudioMixer constant buffer length.\n");
92
93 while (iterations--) {
94 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
95 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
96 mixer.FinishMixing();
97 }
98 }
99
100 {
101 mozilla::AudioMixer mixer;
102 mixer.AddCallback(WrapNotNull(&consumer));
103
104 fprintf(stderr, "Test AudioMixer variable buffer length.\n");
105
106 FillBuffer(a, CHANNEL_LENGTH / 2, GetLowValue<AudioDataValue>());
107 FillBuffer(a + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
108 GetLowValue<AudioDataValue>());
109 FillBuffer(b, CHANNEL_LENGTH / 2, GetHighValue<AudioDataValue>());
110 FillBuffer(b + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
111 GetHighValue<AudioDataValue>());
112 mixer.Mix(a, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
113 mixer.Mix(b, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
114 mixer.FinishMixing();
115 FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
116 FillBuffer(a + CHANNEL_LENGTH, CHANNEL_LENGTH,
117 GetHighValue<AudioDataValue>());
118 FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
119 FillBuffer(b + CHANNEL_LENGTH, CHANNEL_LENGTH,
120 GetLowValue<AudioDataValue>());
121 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
122 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
123 mixer.FinishMixing();
124 FillBuffer(a, CHANNEL_LENGTH / 2, GetLowValue<AudioDataValue>());
125 FillBuffer(a + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
126 GetLowValue<AudioDataValue>());
127 FillBuffer(b, CHANNEL_LENGTH / 2, GetHighValue<AudioDataValue>());
128 FillBuffer(b + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
129 GetHighValue<AudioDataValue>());
130 mixer.Mix(a, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
131 mixer.Mix(b, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
132 mixer.FinishMixing();
133 }
134
135 FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
136 FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
137
138 {
139 mozilla::AudioMixer mixer;
140 mixer.AddCallback(WrapNotNull(&consumer));
141
142 fprintf(stderr, "Test AudioMixer variable channel count.\n");
143
144 mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
145 mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
146 mixer.FinishMixing();
147 mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
148 mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
149 mixer.FinishMixing();
150 mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
151 mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
152 mixer.FinishMixing();
153 }
154
155 {
156 mozilla::AudioMixer mixer;
157 mixer.AddCallback(WrapNotNull(&consumer));
158 fprintf(stderr, "Test AudioMixer variable stream count.\n");
159
160 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
161 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
162 mixer.FinishMixing();
163 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
164 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
165 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
166 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
167 mixer.FinishMixing();
168 mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
169 mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
170 mixer.FinishMixing();
171 }
172 }
173
174 } // namespace audio_mixer
175