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 #ifndef WEBRTC_COMMON_AUDIO_WAV_FILE_H_ 12 #define WEBRTC_COMMON_AUDIO_WAV_FILE_H_ 13 14 #ifdef __cplusplus 15 16 #include <stdint.h> 17 #include <cstddef> 18 #include <string> 19 20 #include "webrtc/base/constructormagic.h" 21 22 namespace webrtc { 23 24 // Interface to provide access to WAV file parameters. 25 class WavFile { 26 public: 27 virtual ~WavFile() {} 28 29 virtual int sample_rate() const = 0; 30 virtual size_t num_channels() const = 0; 31 virtual size_t num_samples() const = 0; 32 33 // Returns a human-readable string containing the audio format. 34 std::string FormatAsString() const; 35 }; 36 37 // Simple C++ class for writing 16-bit PCM WAV files. All error handling is 38 // by calls to RTC_CHECK(), making it unsuitable for anything but debug code. 39 class WavWriter final : public WavFile { 40 public: 41 // Open a new WAV file for writing. 42 WavWriter(const std::string& filename, int sample_rate, size_t num_channels); 43 44 // Close the WAV file, after writing its header. 45 ~WavWriter(); 46 47 // Write additional samples to the file. Each sample is in the range 48 // [-32768,32767], and there must be the previously specified number of 49 // interleaved channels. 50 void WriteSamples(const float* samples, size_t num_samples); 51 void WriteSamples(const int16_t* samples, size_t num_samples); 52 53 int sample_rate() const override { return sample_rate_; } 54 size_t num_channels() const override { return num_channels_; } 55 size_t num_samples() const override { return num_samples_; } 56 57 private: 58 void Close(); 59 const int sample_rate_; 60 const size_t num_channels_; 61 size_t num_samples_; // Total number of samples written to file. 62 FILE* file_handle_; // Output file, owned by this class 63 64 RTC_DISALLOW_COPY_AND_ASSIGN(WavWriter); 65 }; 66 67 // Follows the conventions of WavWriter. 68 class WavReader final : public WavFile { 69 public: 70 // Opens an existing WAV file for reading. 71 explicit WavReader(const std::string& filename); 72 73 // Close the WAV file. 74 ~WavReader(); 75 76 // Returns the number of samples read. If this is less than requested, 77 // verifies that the end of the file was reached. 78 size_t ReadSamples(size_t num_samples, float* samples); 79 size_t ReadSamples(size_t num_samples, int16_t* samples); 80 81 int sample_rate() const override { return sample_rate_; } 82 size_t num_channels() const override { return num_channels_; } 83 size_t num_samples() const override { return num_samples_; } 84 85 private: 86 void Close(); 87 int sample_rate_; 88 size_t num_channels_; 89 size_t num_samples_; // Total number of samples in the file. 90 size_t num_samples_remaining_; 91 FILE* file_handle_; // Input file, owned by this class. 92 93 RTC_DISALLOW_COPY_AND_ASSIGN(WavReader); 94 }; 95 96 } // namespace webrtc 97 98 extern "C" { 99 #endif // __cplusplus 100 101 // C wrappers for the WavWriter class. 102 typedef struct rtc_WavWriter rtc_WavWriter; 103 rtc_WavWriter* rtc_WavOpen(const char* filename, 104 int sample_rate, 105 size_t num_channels); 106 void rtc_WavClose(rtc_WavWriter* wf); 107 void rtc_WavWriteSamples(rtc_WavWriter* wf, 108 const float* samples, 109 size_t num_samples); 110 int rtc_WavSampleRate(const rtc_WavWriter* wf); 111 size_t rtc_WavNumChannels(const rtc_WavWriter* wf); 112 size_t rtc_WavNumSamples(const rtc_WavWriter* wf); 113 114 #ifdef __cplusplus 115 } // extern "C" 116 #endif 117 118 #endif // WEBRTC_COMMON_AUDIO_WAV_FILE_H_ 119
