1/*
2 *  Copyright (c) 2014 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// MSVC++ requires this to be set before any other includes to get M_PI.
12#define _USE_MATH_DEFINES
13
14#include <cmath>
15#include <limits>
16
17#include "testing/gtest/include/gtest/gtest.h"
18#include "webrtc/base/compile_assert.h"
19#include "webrtc/common_audio/wav_header.h"
20#include "webrtc/common_audio/wav_writer.h"
21#include "webrtc/test/testsupport/fileutils.h"
22
23static const float kSamples[] = {0.0, 10.0, 4e4, -1e9};
24
25// Write a tiny WAV file with the C++ interface and verify the result.
26TEST(WavWriterTest, CPP) {
27  const std::string outfile = webrtc::test::OutputPath() + "wavtest1.wav";
28  static const uint32_t kNumSamples = 3;
29  {
30    webrtc::WavFile w(outfile, 14099, 1);
31    EXPECT_EQ(14099, w.sample_rate());
32    EXPECT_EQ(1, w.num_channels());
33    EXPECT_EQ(0u, w.num_samples());
34    w.WriteSamples(kSamples, kNumSamples);
35    EXPECT_EQ(kNumSamples, w.num_samples());
36  }
37  static const uint8_t kExpectedContents[] = {
38    'R', 'I', 'F', 'F',
39    42, 0, 0, 0,  // size of whole file - 8: 6 + 44 - 8
40    'W', 'A', 'V', 'E',
41    'f', 'm', 't', ' ',
42    16, 0, 0, 0,  // size of fmt block - 8: 24 - 8
43    1, 0,  // format: PCM (1)
44    1, 0,  // channels: 1
45    0x13, 0x37, 0, 0,  // sample rate: 14099
46    0x26, 0x6e, 0, 0,  // byte rate: 2 * 14099
47    2, 0,  // block align: NumChannels * BytesPerSample
48    16, 0,  // bits per sample: 2 * 8
49    'd', 'a', 't', 'a',
50    6, 0, 0, 0,  // size of payload: 6
51    0, 0,  // first sample: 0.0
52    10, 0,  // second sample: 10.0
53    0xff, 0x7f,  // third sample: 4e4 (saturated)
54  };
55  static const int kContentSize =
56      webrtc::kWavHeaderSize + kNumSamples * sizeof(int16_t);
57  COMPILE_ASSERT(sizeof(kExpectedContents) == kContentSize, content_size);
58  EXPECT_EQ(size_t(kContentSize), webrtc::test::GetFileSize(outfile));
59  FILE* f = fopen(outfile.c_str(), "rb");
60  ASSERT_TRUE(f);
61  uint8_t contents[kContentSize];
62  ASSERT_EQ(1u, fread(contents, kContentSize, 1, f));
63  EXPECT_EQ(0, fclose(f));
64  EXPECT_EQ(0, memcmp(kExpectedContents, contents, kContentSize));
65}
66
67// Write a tiny WAV file with the C interface and verify the result.
68TEST(WavWriterTest, C) {
69  const std::string outfile = webrtc::test::OutputPath() + "wavtest2.wav";
70  rtc_WavFile *w = rtc_WavOpen(outfile.c_str(), 11904, 2);
71  EXPECT_EQ(11904, rtc_WavSampleRate(w));
72  EXPECT_EQ(2, rtc_WavNumChannels(w));
73  EXPECT_EQ(0u, rtc_WavNumSamples(w));
74  static const uint32_t kNumSamples = 4;
75  rtc_WavWriteSamples(w, &kSamples[0], 2);
76  EXPECT_EQ(2u, rtc_WavNumSamples(w));
77  rtc_WavWriteSamples(w, &kSamples[2], kNumSamples - 2);
78  EXPECT_EQ(kNumSamples, rtc_WavNumSamples(w));
79  rtc_WavClose(w);
80  static const uint8_t kExpectedContents[] = {
81    'R', 'I', 'F', 'F',
82    44, 0, 0, 0,  // size of whole file - 8: 8 + 44 - 8
83    'W', 'A', 'V', 'E',
84    'f', 'm', 't', ' ',
85    16, 0, 0, 0,  // size of fmt block - 8: 24 - 8
86    1, 0,  // format: PCM (1)
87    2, 0,  // channels: 2
88    0x80, 0x2e, 0, 0,  // sample rate: 11904
89    0, 0xba, 0, 0,  // byte rate: 2 * 2 * 11904
90    4, 0,  // block align: NumChannels * BytesPerSample
91    16, 0,  // bits per sample: 2 * 8
92    'd', 'a', 't', 'a',
93    8, 0, 0, 0,  // size of payload: 8
94    0, 0,  // first sample: 0.0
95    10, 0,  // second sample: 10.0
96    0xff, 0x7f,  // third sample: 4e4 (saturated)
97    0, 0x80,  // fourth sample: -1e9 (saturated)
98  };
99  static const int kContentSize =
100      webrtc::kWavHeaderSize + kNumSamples * sizeof(int16_t);
101  COMPILE_ASSERT(sizeof(kExpectedContents) == kContentSize, content_size);
102  EXPECT_EQ(size_t(kContentSize), webrtc::test::GetFileSize(outfile));
103  FILE* f = fopen(outfile.c_str(), "rb");
104  ASSERT_TRUE(f);
105  uint8_t contents[kContentSize];
106  ASSERT_EQ(1u, fread(contents, kContentSize, 1, f));
107  EXPECT_EQ(0, fclose(f));
108  EXPECT_EQ(0, memcmp(kExpectedContents, contents, kContentSize));
109}
110
111// Write a larger WAV file. You can listen to this file to sanity-check it.
112TEST(WavWriterTest, LargeFile) {
113  std::string outfile = webrtc::test::OutputPath() + "wavtest3.wav";
114  static const int kSampleRate = 8000;
115  static const int kNumChannels = 2;
116  static const uint32_t kNumSamples = 3 * kSampleRate * kNumChannels;
117  float samples[kNumSamples];
118  for (uint32_t i = 0; i < kNumSamples; i += kNumChannels) {
119    // A nice periodic beeping sound.
120    static const double kToneHz = 440;
121    const double t = static_cast<double>(i) / (kNumChannels * kSampleRate);
122    const double x =
123        std::numeric_limits<int16_t>::max() * std::sin(t * kToneHz * 2 * M_PI);
124    samples[i] = std::pow(std::sin(t * 2 * 2 * M_PI), 10) * x;
125    samples[i + 1] = std::pow(std::cos(t * 2 * 2 * M_PI), 10) * x;
126  }
127  {
128    webrtc::WavFile w(outfile, kSampleRate, kNumChannels);
129    EXPECT_EQ(kSampleRate, w.sample_rate());
130    EXPECT_EQ(kNumChannels, w.num_channels());
131    EXPECT_EQ(0u, w.num_samples());
132    w.WriteSamples(samples, kNumSamples);
133    EXPECT_EQ(kNumSamples, w.num_samples());
134  }
135  EXPECT_EQ(sizeof(int16_t) * kNumSamples + webrtc::kWavHeaderSize,
136            webrtc::test::GetFileSize(outfile));
137}
138