/* * Copyright (c) 2014 The WebRTC project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ #ifndef WEBRTC_COMMON_AUDIO_WAV_HEADER_H_ #define WEBRTC_COMMON_AUDIO_WAV_HEADER_H_ #include #include namespace webrtc { static const size_t kWavHeaderSize = 44; class ReadableWav { public: // Returns the number of bytes read. size_t virtual Read(void* buf, size_t num_bytes) = 0; virtual ~ReadableWav() {} }; enum WavFormat { kWavFormatPcm = 1, // PCM, each sample of size bytes_per_sample kWavFormatALaw = 6, // 8-bit ITU-T G.711 A-law kWavFormatMuLaw = 7, // 8-bit ITU-T G.711 mu-law }; // Return true if the given parameters will make a well-formed WAV header. bool CheckWavParameters(int num_channels, int sample_rate, WavFormat format, int bytes_per_sample, uint32_t num_samples); // Write a kWavHeaderSize bytes long WAV header to buf. The payload that // follows the header is supposed to have the specified number of interleaved // channels and contain the specified total number of samples of the specified // type. CHECKs the input parameters for validity. void WriteWavHeader(uint8_t* buf, int num_channels, int sample_rate, WavFormat format, int bytes_per_sample, uint32_t num_samples); // Read a WAV header from an implemented ReadableWav and parse the values into // the provided output parameters. ReadableWav is used because the header can // be variably sized. Returns false if the header is invalid. bool ReadWavHeader(ReadableWav* readable, int* num_channels, int* sample_rate, WavFormat* format, int* bytes_per_sample, uint32_t* num_samples); } // namespace webrtc #endif // WEBRTC_COMMON_AUDIO_WAV_HEADER_H_