OpenShot Audio Library | OpenShotAudio  0.3.0
juce_AudioSourcePlayer.cpp
1 /*
2  ==============================================================================
3 
4  This file is part of the JUCE library.
5  Copyright (c) 2017 - ROLI Ltd.
6 
7  JUCE is an open source library subject to commercial or open-source
8  licensing.
9 
10  The code included in this file is provided under the terms of the ISC license
11  http://www.isc.org/downloads/software-support-policy/isc-license. Permission
12  To use, copy, modify, and/or distribute this software for any purpose with or
13  without fee is hereby granted provided that the above copyright notice and
14  this permission notice appear in all copies.
15 
16  JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
17  EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
18  DISCLAIMED.
19 
20  ==============================================================================
21 */
22 
23 namespace juce
24 {
25 
27 {
28 }
29 
31 {
32  setSource (nullptr);
33 }
34 
36 {
37  if (source != newSource)
38  {
39  auto* oldSource = source;
40 
41  if (newSource != nullptr && bufferSize > 0 && sampleRate > 0)
42  newSource->prepareToPlay (bufferSize, sampleRate);
43 
44  {
45  const ScopedLock sl (readLock);
46  source = newSource;
47  }
48 
49  if (oldSource != nullptr)
50  oldSource->releaseResources();
51  }
52 }
53 
54 void AudioSourcePlayer::setGain (const float newGain) noexcept
55 {
56  gain = newGain;
57 }
58 
59 void AudioSourcePlayer::audioDeviceIOCallback (const float** inputChannelData,
60  int totalNumInputChannels,
61  float** outputChannelData,
62  int totalNumOutputChannels,
63  int numSamples)
64 {
65  // these should have been prepared by audioDeviceAboutToStart()...
66  jassert (sampleRate > 0 && bufferSize > 0);
67 
68  const ScopedLock sl (readLock);
69 
70  if (source != nullptr)
71  {
72  int numActiveChans = 0, numInputs = 0, numOutputs = 0;
73 
74  // messy stuff needed to compact the channels down into an array
75  // of non-zero pointers..
76  for (int i = 0; i < totalNumInputChannels; ++i)
77  {
78  if (inputChannelData[i] != nullptr)
79  {
80  inputChans [numInputs++] = inputChannelData[i];
81  if (numInputs >= numElementsInArray (inputChans))
82  break;
83  }
84  }
85 
86  for (int i = 0; i < totalNumOutputChannels; ++i)
87  {
88  if (outputChannelData[i] != nullptr)
89  {
90  outputChans [numOutputs++] = outputChannelData[i];
91  if (numOutputs >= numElementsInArray (outputChans))
92  break;
93  }
94  }
95 
96  if (numInputs > numOutputs)
97  {
98  // if there aren't enough output channels for the number of
99  // inputs, we need to create some temporary extra ones (can't
100  // use the input data in case it gets written to)
101  tempBuffer.setSize (numInputs - numOutputs, numSamples,
102  false, false, true);
103 
104  for (int i = 0; i < numOutputs; ++i)
105  {
106  channels[numActiveChans] = outputChans[i];
107  memcpy (channels[numActiveChans], inputChans[i], (size_t) numSamples * sizeof (float));
108  ++numActiveChans;
109  }
110 
111  for (int i = numOutputs; i < numInputs; ++i)
112  {
113  channels[numActiveChans] = tempBuffer.getWritePointer (i - numOutputs);
114  memcpy (channels[numActiveChans], inputChans[i], (size_t) numSamples * sizeof (float));
115  ++numActiveChans;
116  }
117  }
118  else
119  {
120  for (int i = 0; i < numInputs; ++i)
121  {
122  channels[numActiveChans] = outputChans[i];
123  memcpy (channels[numActiveChans], inputChans[i], (size_t) numSamples * sizeof (float));
124  ++numActiveChans;
125  }
126 
127  for (int i = numInputs; i < numOutputs; ++i)
128  {
129  channels[numActiveChans] = outputChans[i];
130  zeromem (channels[numActiveChans], (size_t) numSamples * sizeof (float));
131  ++numActiveChans;
132  }
133  }
134 
135  AudioBuffer<float> buffer (channels, numActiveChans, numSamples);
136 
137  AudioSourceChannelInfo info (&buffer, 0, numSamples);
138  source->getNextAudioBlock (info);
139 
140  for (int i = info.buffer->getNumChannels(); --i >= 0;)
141  buffer.applyGainRamp (i, info.startSample, info.numSamples, lastGain, gain);
142 
143  lastGain = gain;
144  }
145  else
146  {
147  for (int i = 0; i < totalNumOutputChannels; ++i)
148  if (outputChannelData[i] != nullptr)
149  zeromem (outputChannelData[i], (size_t) numSamples * sizeof (float));
150  }
151 }
152 
154 {
156  device->getCurrentBufferSizeSamples());
157 }
158 
159 void AudioSourcePlayer::prepareToPlay (double newSampleRate, int newBufferSize)
160 {
161  sampleRate = newSampleRate;
162  bufferSize = newBufferSize;
163  zeromem (channels, sizeof (channels));
164 
165  if (source != nullptr)
166  source->prepareToPlay (bufferSize, sampleRate);
167 }
168 
170 {
171  if (source != nullptr)
172  source->releaseResources();
173 
174  sampleRate = 0.0;
175  bufferSize = 0;
176 
177  tempBuffer.setSize (2, 8);
178 }
179 
180 } // namespace juce
void setSize(int newNumChannels, int newNumSamples, bool keepExistingContent=false, bool clearExtraSpace=false, bool avoidReallocating=false)
Type * getWritePointer(int channelNumber) noexcept
int getNumChannels() const noexcept
void applyGainRamp(int channel, int startSample, int numSamples, Type startGain, Type endGain) noexcept
virtual double getCurrentSampleRate()=0
virtual int getCurrentBufferSizeSamples()=0
void setGain(float newGain) noexcept
void setSource(AudioSource *newSource)
void audioDeviceIOCallback(const float **inputChannelData, int totalNumInputChannels, float **outputChannelData, int totalNumOutputChannels, int numSamples) override
void prepareToPlay(double sampleRate, int blockSize)
void audioDeviceAboutToStart(AudioIODevice *device) override
virtual void releaseResources()=0
virtual void prepareToPlay(int samplesPerBlockExpected, double sampleRate)=0
virtual void getNextAudioBlock(const AudioSourceChannelInfo &bufferToFill)=0
AudioBuffer< float > * buffer