1/*
2 * Copyright (C) 2011 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 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef MultiChannelResampler_h
30#define MultiChannelResampler_h
31
32#include "platform/audio/SincResampler.h"
33#include "wtf/Noncopyable.h"
34#include "wtf/OwnPtr.h"
35
36namespace blink {
37
38class AudioBus;
39
40class PLATFORM_EXPORT MultiChannelResampler {
41    WTF_MAKE_NONCOPYABLE(MultiChannelResampler);
42public:
43    MultiChannelResampler(double scaleFactor, unsigned numberOfChannels);
44
45    // Process given AudioSourceProvider for streaming applications.
46    void process(AudioSourceProvider*, AudioBus* destination, size_t framesToProcess);
47
48private:
49    // FIXME: the mac port can have a more highly optimized implementation based on CoreAudio
50    // instead of SincResampler. For now the default implementation will be used on all ports.
51    // https://bugs.webkit.org/show_bug.cgi?id=75118
52
53    // Each channel will be resampled using a high-quality SincResampler.
54    Vector<OwnPtr<SincResampler> > m_kernels;
55
56    unsigned m_numberOfChannels;
57};
58
59} // namespace blink
60
61#endif // MultiChannelResampler_h
62