reverb.cc | Explore in Territory

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
 * are met:
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 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
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#include "third_party/blink/renderer/platform/audio/reverb.h"

#include <math.h>

#include <algorithm>
#include <memory>
#include <utility>

#include "build/build_config.h"
#include "third_party/blink/renderer/platform/audio/audio_bus.h"
#include "third_party/blink/renderer/platform/audio/vector_math.h"
#include "third_party/blink/renderer/platform/wtf/math_extras.h"
#include "third_party/fdlibm/ieee754.h"

namespace blink {

// Empirical gain calibration tested across many impulse responses to ensure
// perceived volume is same as dry (unprocessed) signal
const float kGainCalibration = …;
const float kGainCalibrationSampleRate = …;

// A minimum power value to when normalizing a silent (or very quiet) impulse
// response
const float kMinPower = …;

static float CalculateNormalizationScale(AudioBus* response) { … }

Reverb::Reverb(AudioBus* impulse_response,
               unsigned render_slice_size,
               unsigned max_fft_size,
               bool use_background_threads,
               bool normalize) { … }

void Reverb::Initialize(AudioBus* impulse_response_buffer,
                        unsigned render_slice_size,
                        unsigned max_fft_size,
                        bool use_background_threads,
                        float scale) { … }

void Reverb::Process(const AudioBus* source_bus,
                     AudioBus* destination_bus,
                     uint32_t frames_to_process) { … }

void Reverb::Reset() { … }

size_t Reverb::LatencyFrames() const { … }

}  // namespace blink
chromium/third_party/blink/renderer/platform/audio/reverb.cc
