| /* |
| * Copyright (c) 2013 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. |
| */ |
| |
| // Modified from the Chromium original here: |
| // src/media/base/sinc_resampler_unittest.cc |
| |
| #ifndef WEBRTC_COMMON_AUDIO_RESAMPLER_SINUSOIDAL_LINEAR_CHIRP_SOURCE_H_ |
| #define WEBRTC_COMMON_AUDIO_RESAMPLER_SINUSOIDAL_LINEAR_CHIRP_SOURCE_H_ |
| |
| #include "webrtc/base/constructormagic.h" |
| #include "webrtc/common_audio/resampler/sinc_resampler.h" |
| |
| namespace webrtc { |
| |
| // Fake audio source for testing the resampler. Generates a sinusoidal linear |
| // chirp (http://en.wikipedia.org/wiki/Chirp) which can be tuned to stress the |
| // resampler for the specific sample rate conversion being used. |
| class SinusoidalLinearChirpSource : public SincResamplerCallback { |
| public: |
| // |delay_samples| can be used to insert a fractional sample delay into the |
| // source. It will produce zeros until non-negative time is reached. |
| SinusoidalLinearChirpSource(int sample_rate, size_t samples, |
| double max_frequency, double delay_samples); |
| |
| virtual ~SinusoidalLinearChirpSource() {} |
| |
| void Run(size_t frames, float* destination) override; |
| |
| double Frequency(size_t position); |
| |
| private: |
| enum { |
| kMinFrequency = 5 |
| }; |
| |
| int sample_rate_; |
| size_t total_samples_; |
| double max_frequency_; |
| double k_; |
| size_t current_index_; |
| double delay_samples_; |
| |
| RTC_DISALLOW_COPY_AND_ASSIGN(SinusoidalLinearChirpSource); |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // WEBRTC_COMMON_AUDIO_RESAMPLER_SINUSOIDAL_LINEAR_CHIRP_SOURCE_H_ |