|  | /* | 
|  | *  Copyright (c) 2017 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 MODULES_AUDIO_PROCESSING_TEST_ECHO_CANCELLER_TEST_TOOLS_H_ | 
|  | #define MODULES_AUDIO_PROCESSING_TEST_ECHO_CANCELLER_TEST_TOOLS_H_ | 
|  |  | 
|  | #include <algorithm> | 
|  | #include <vector> | 
|  |  | 
|  | #include "api/array_view.h" | 
|  | #include "rtc_base/constructormagic.h" | 
|  | #include "rtc_base/random.h" | 
|  |  | 
|  | namespace webrtc { | 
|  |  | 
|  | // Randomizes the elements in a vector with values -32767.f:32767.f. | 
|  | void RandomizeSampleVector(Random* random_generator, rtc::ArrayView<float> v); | 
|  |  | 
|  | // Class for delaying a signal a fixed number of samples. | 
|  | template <typename T> | 
|  | class DelayBuffer { | 
|  | public: | 
|  | explicit DelayBuffer(size_t delay) : buffer_(delay) {} | 
|  | ~DelayBuffer() = default; | 
|  |  | 
|  | // Produces a delayed signal copy of x. | 
|  | void Delay(rtc::ArrayView<const T> x, rtc::ArrayView<T> x_delayed); | 
|  |  | 
|  | private: | 
|  | std::vector<T> buffer_; | 
|  | size_t next_insert_index_ = 0; | 
|  | RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(DelayBuffer); | 
|  | }; | 
|  |  | 
|  | }  // namespace webrtc | 
|  |  | 
|  | #endif  // MODULES_AUDIO_PROCESSING_TEST_ECHO_CANCELLER_TEST_TOOLS_H_ |