1/*
2 * Copyright (C) 2010, Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1.  Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2.  Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#ifndef DelayDSPKernel_h
26#define DelayDSPKernel_h
27
28#include "AudioArray.h"
29#include "AudioDSPKernel.h"
30#include "DelayProcessor.h"
31
32namespace WebCore {
33
34class DelayProcessor;
35
36class DelayDSPKernel : public AudioDSPKernel {
37public:
38    explicit DelayDSPKernel(DelayProcessor*);
39    DelayDSPKernel(double maxDelayTime, float sampleRate);
40
41    virtual void process(const float* source, float* destination, size_t framesToProcess) override;
42    virtual void reset() override;
43
44    double maxDelayTime() const { return m_maxDelayTime; }
45
46    void setDelayFrames(double numberOfFrames) { m_desiredDelayFrames = numberOfFrames; }
47
48    virtual double tailTime() const override;
49    virtual double latencyTime() const override;
50
51private:
52    AudioFloatArray m_buffer;
53    double m_maxDelayTime;
54    int m_writeIndex;
55    double m_currentDelayTime;
56    double m_smoothingRate;
57    bool m_firstTime;
58    double m_desiredDelayFrames;
59
60    AudioFloatArray m_delayTimes;
61
62    DelayProcessor* delayProcessor() { return static_cast<DelayProcessor*>(processor()); }
63    size_t bufferLengthForDelay(double delayTime, double sampleRate) const;
64};
65
66} // namespace WebCore
67
68#endif // DelayDSPKernel_h
69