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/common_audio/wav_header.h"
19 #include "webrtc/common_audio/wav_file.h"
20 #include "webrtc/test/testsupport/fileutils.h"
21 
22 namespace webrtc {
23 
24 static const float kSamples[] = {0.0, 10.0, 4e4, -1e9};
25 
26 // Write a tiny WAV file with the C++ interface and verify the result.
TEST(WavWriterTest,CPP)27 TEST(WavWriterTest, CPP) {
28   const std::string outfile = test::OutputPath() + "wavtest1.wav";
29   static const size_t kNumSamples = 3;
30   {
31     WavWriter w(outfile, 14099, 1);
32     EXPECT_EQ(14099, w.sample_rate());
33     EXPECT_EQ(1u, w.num_channels());
34     EXPECT_EQ(0u, w.num_samples());
35     w.WriteSamples(kSamples, kNumSamples);
36     EXPECT_EQ(kNumSamples, w.num_samples());
37   }
38   // Write some extra "metadata" to the file that should be silently ignored
39   // by WavReader. We don't use WavWriter directly for this because it doesn't
40   // support metadata.
41   static const uint8_t kMetadata[] = {101, 202};
42   {
43     FILE* f = fopen(outfile.c_str(), "ab");
44     ASSERT_TRUE(f);
45     ASSERT_EQ(1u, fwrite(kMetadata, sizeof(kMetadata), 1, f));
46     fclose(f);
47   }
48   static const uint8_t kExpectedContents[] = {
49     'R', 'I', 'F', 'F',
50     42, 0, 0, 0,  // size of whole file - 8: 6 + 44 - 8
51     'W', 'A', 'V', 'E',
52     'f', 'm', 't', ' ',
53     16, 0, 0, 0,  // size of fmt block - 8: 24 - 8
54     1, 0,  // format: PCM (1)
55     1, 0,  // channels: 1
56     0x13, 0x37, 0, 0,  // sample rate: 14099
57     0x26, 0x6e, 0, 0,  // byte rate: 2 * 14099
58     2, 0,  // block align: NumChannels * BytesPerSample
59     16, 0,  // bits per sample: 2 * 8
60     'd', 'a', 't', 'a',
61     6, 0, 0, 0,  // size of payload: 6
62     0, 0,  // first sample: 0.0
63     10, 0,  // second sample: 10.0
64     0xff, 0x7f,  // third sample: 4e4 (saturated)
65     kMetadata[0], kMetadata[1],
66   };
67   static const size_t kContentSize =
68       kWavHeaderSize + kNumSamples * sizeof(int16_t) + sizeof(kMetadata);
69   static_assert(sizeof(kExpectedContents) == kContentSize, "content size");
70   EXPECT_EQ(kContentSize, test::GetFileSize(outfile));
71   FILE* f = fopen(outfile.c_str(), "rb");
72   ASSERT_TRUE(f);
73   uint8_t contents[kContentSize];
74   ASSERT_EQ(1u, fread(contents, kContentSize, 1, f));
75   EXPECT_EQ(0, fclose(f));
76   EXPECT_EQ(0, memcmp(kExpectedContents, contents, kContentSize));
77 
78   {
79     WavReader r(outfile);
80     EXPECT_EQ(14099, r.sample_rate());
81     EXPECT_EQ(1u, r.num_channels());
82     EXPECT_EQ(kNumSamples, r.num_samples());
83     static const float kTruncatedSamples[] = {0.0, 10.0, 32767.0};
84     float samples[kNumSamples];
85     EXPECT_EQ(kNumSamples, r.ReadSamples(kNumSamples, samples));
86     EXPECT_EQ(0, memcmp(kTruncatedSamples, samples, sizeof(samples)));
87     EXPECT_EQ(0u, r.ReadSamples(kNumSamples, samples));
88   }
89 }
90 
91 // Write a tiny WAV file with the C interface and verify the result.
TEST(WavWriterTest,C)92 TEST(WavWriterTest, C) {
93   const std::string outfile = test::OutputPath() + "wavtest2.wav";
94   rtc_WavWriter* w = rtc_WavOpen(outfile.c_str(), 11904, 2);
95   EXPECT_EQ(11904, rtc_WavSampleRate(w));
96   EXPECT_EQ(2u, rtc_WavNumChannels(w));
97   EXPECT_EQ(0u, rtc_WavNumSamples(w));
98   static const size_t kNumSamples = 4;
99   rtc_WavWriteSamples(w, &kSamples[0], 2);
100   EXPECT_EQ(2u, rtc_WavNumSamples(w));
101   rtc_WavWriteSamples(w, &kSamples[2], kNumSamples - 2);
102   EXPECT_EQ(kNumSamples, rtc_WavNumSamples(w));
103   rtc_WavClose(w);
104   static const uint8_t kExpectedContents[] = {
105     'R', 'I', 'F', 'F',
106     44, 0, 0, 0,  // size of whole file - 8: 8 + 44 - 8
107     'W', 'A', 'V', 'E',
108     'f', 'm', 't', ' ',
109     16, 0, 0, 0,  // size of fmt block - 8: 24 - 8
110     1, 0,  // format: PCM (1)
111     2, 0,  // channels: 2
112     0x80, 0x2e, 0, 0,  // sample rate: 11904
113     0, 0xba, 0, 0,  // byte rate: 2 * 2 * 11904
114     4, 0,  // block align: NumChannels * BytesPerSample
115     16, 0,  // bits per sample: 2 * 8
116     'd', 'a', 't', 'a',
117     8, 0, 0, 0,  // size of payload: 8
118     0, 0,  // first sample: 0.0
119     10, 0,  // second sample: 10.0
120     0xff, 0x7f,  // third sample: 4e4 (saturated)
121     0, 0x80,  // fourth sample: -1e9 (saturated)
122   };
123   static const size_t kContentSize =
124       kWavHeaderSize + kNumSamples * sizeof(int16_t);
125   static_assert(sizeof(kExpectedContents) == kContentSize, "content size");
126   EXPECT_EQ(kContentSize, test::GetFileSize(outfile));
127   FILE* f = fopen(outfile.c_str(), "rb");
128   ASSERT_TRUE(f);
129   uint8_t contents[kContentSize];
130   ASSERT_EQ(1u, fread(contents, kContentSize, 1, f));
131   EXPECT_EQ(0, fclose(f));
132   EXPECT_EQ(0, memcmp(kExpectedContents, contents, kContentSize));
133 }
134 
135 // Write a larger WAV file. You can listen to this file to sanity-check it.
TEST(WavWriterTest,LargeFile)136 TEST(WavWriterTest, LargeFile) {
137   std::string outfile = test::OutputPath() + "wavtest3.wav";
138   static const int kSampleRate = 8000;
139   static const size_t kNumChannels = 2;
140   static const size_t kNumSamples = 3 * kSampleRate * kNumChannels;
141   float samples[kNumSamples];
142   for (size_t i = 0; i < kNumSamples; i += kNumChannels) {
143     // A nice periodic beeping sound.
144     static const double kToneHz = 440;
145     const double t = static_cast<double>(i) / (kNumChannels * kSampleRate);
146     const double x =
147         std::numeric_limits<int16_t>::max() * std::sin(t * kToneHz * 2 * M_PI);
148     samples[i] = std::pow(std::sin(t * 2 * 2 * M_PI), 10) * x;
149     samples[i + 1] = std::pow(std::cos(t * 2 * 2 * M_PI), 10) * x;
150   }
151   {
152     WavWriter w(outfile, kSampleRate, kNumChannels);
153     EXPECT_EQ(kSampleRate, w.sample_rate());
154     EXPECT_EQ(kNumChannels, w.num_channels());
155     EXPECT_EQ(0u, w.num_samples());
156     w.WriteSamples(samples, kNumSamples);
157     EXPECT_EQ(kNumSamples, w.num_samples());
158   }
159   EXPECT_EQ(sizeof(int16_t) * kNumSamples + kWavHeaderSize,
160             test::GetFileSize(outfile));
161 
162   {
163     WavReader r(outfile);
164     EXPECT_EQ(kSampleRate, r.sample_rate());
165     EXPECT_EQ(kNumChannels, r.num_channels());
166     EXPECT_EQ(kNumSamples, r.num_samples());
167 
168     float read_samples[kNumSamples];
169     EXPECT_EQ(kNumSamples, r.ReadSamples(kNumSamples, read_samples));
170     for (size_t i = 0; i < kNumSamples; ++i)
171       EXPECT_NEAR(samples[i], read_samples[i], 1);
172 
173     EXPECT_EQ(0u, r.ReadSamples(kNumSamples, read_samples));
174   }
175 }
176 
177 }  // namespace webrtc
178