OpenShot Library | OpenShotAudio  0.2.2
juce_ProcessContext.h
1 
2 /** @weakgroup juce_dsp-processors
3  * @{
4  */
5 /*
6  ==============================================================================
7 
8  This file is part of the JUCE library.
9  Copyright (c) 2017 - ROLI Ltd.
10 
11  JUCE is an open source library subject to commercial or open-source
12  licensing.
13 
14  By using JUCE, you agree to the terms of both the JUCE 5 End-User License
15  Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
16  27th April 2017).
17 
18  End User License Agreement: www.juce.com/juce-5-licence
19  Privacy Policy: www.juce.com/juce-5-privacy-policy
20 
21  Or: You may also use this code under the terms of the GPL v3 (see
22  www.gnu.org/licenses).
23 
24  JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
25  EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
26  DISCLAIMED.
27 
28  ==============================================================================
29 */
30 
31 namespace juce
32 {
33 namespace dsp
34 {
35 
36 /**
37  This structure is passed into a DSP algorithm's prepare() method, and contains
38  information about various aspects of the context in which it can expect to be called.
39 
40  @tags{DSP}
41 */
43 {
44  /** The sample rate that will be used for the data that is sent to the processor. */
45  double sampleRate;
46 
47  /** The maximum number of samples that will be in the blocks sent to process() method. */
49 
50  /** The number of channels that the process() method will be expected to handle. */
51  uint32 numChannels;
52 };
53 
54 //==============================================================================
55 /**
56  This is a handy base class for the state of a processor (such as parameter values)
57  which is typically shared among several processors. This is useful for multi-mono
58  filters which share the same state among several mono processors.
59 
60  @tags{DSP}
61 */
63 {
64  /** The ProcessorState structure is ref-counted, so this is a handy type that can be used
65  as a pointer to one.
66  */
68 };
69 
70 //==============================================================================
71 /**
72  Contains context information that is passed into an algorithm's process method.
73 
74  This context is intended for use in situations where a single block is being used
75  for both the input and output, so it will return the same object for both its
76  getInputBlock() and getOutputBlock() methods.
77 
78  @see ProcessContextNonReplacing
79 
80  @tags{DSP}
81 */
82 template <typename ContextSampleType>
84 {
85 public:
86  /** The type of a single sample (which may be a vector if multichannel). */
87  using SampleType = ContextSampleType;
88  /** The type of audio block that this context handles. */
91 
92  /** Creates a ProcessContextReplacing that uses the given audio block.
93  Note that the caller must not delete the block while it is still in use by this object!
94  */
95  ProcessContextReplacing (AudioBlockType& block) noexcept : ioBlock (block) {}
96 
99 
100  /** Returns the audio block to use as the input to a process function. */
101  const ConstAudioBlockType& getInputBlock() const noexcept { return constBlock; }
102 
103  /** Returns the audio block to use as the output to a process function. */
104  AudioBlockType& getOutputBlock() const noexcept { return ioBlock; }
105 
106  /** All process context classes will define this constant method so that templated
107  code can determine whether the input and output blocks refer to the same buffer,
108  or to two different ones.
109  */
110  static constexpr bool usesSeparateInputAndOutputBlocks() { return false; }
111 
112  /** If set to true, then a processor's process() method is expected to do whatever
113  is appropriate for it to be in a bypassed state.
114  */
115  bool isBypassed = false;
116 
117 private:
118  AudioBlockType& ioBlock;
119  ConstAudioBlockType constBlock { ioBlock };
120 };
121 
122 //==============================================================================
123 /**
124  Contains context information that is passed into an algorithm's process method.
125 
126  This context is intended for use in situations where two different blocks are being
127  used the input and output to the process algorithm, so the processor must read from
128  the block returned by getInputBlock() and write its results to the block returned by
129  getOutputBlock().
130 
131  @see ProcessContextReplacing
132 
133  @tags{DSP}
134 */
135 template <typename ContextSampleType>
137 {
138 public:
139  /** The type of a single sample (which may be a vector if multichannel). */
140  using SampleType = ContextSampleType;
141  /** The type of audio block that this context handles. */
144 
145  /** Creates a ProcessContextReplacing that uses the given input and output blocks.
146  Note that the caller must not delete these blocks while they are still in use by this object!
147  */
149  : inputBlock (input), outputBlock (output)
150  {
151  // If the input and output blocks are the same then you should use
152  // ProcessContextReplacing instead.
153  jassert (input != output);
154  }
155 
158 
159  /** Returns the audio block to use as the input to a process function. */
160  const ConstAudioBlockType& getInputBlock() const noexcept { return inputBlock; }
161 
162  /** Returns the audio block to use as the output to a process function. */
163  AudioBlockType& getOutputBlock() const noexcept { return outputBlock; }
164 
165  /** All process context classes will define this constant method so that templated
166  code can determine whether the input and output blocks refer to the same buffer,
167  or to two different ones.
168  */
169  static constexpr bool usesSeparateInputAndOutputBlocks() { return true; }
170 
171  /** If set to true, then a processor's process() method is expected to do whatever
172  is appropriate for it to be in a bypassed state.
173  */
174  bool isBypassed = false;
175 
176 private:
177  ConstAudioBlockType inputBlock;
178  AudioBlockType& outputBlock;
179 };
180 
181 } // namespace dsp
182 } // namespace juce
183 
184 /** @}*/
const ConstAudioBlockType & getInputBlock() const noexcept
Returns the audio block to use as the input to a process function.
uint32 numChannels
The number of channels that the process() method will be expected to handle.
ProcessContextNonReplacing(const ConstAudioBlockType &input, AudioBlockType &output) noexcept
Creates a ProcessContextReplacing that uses the given input and output blocks.
double sampleRate
The sample rate that will be used for the data that is sent to the processor.
Minimal and lightweight data-structure which contains a list of pointers to channels containing some ...
ContextSampleType SampleType
The type of a single sample (which may be a vector if multichannel).
uint32 maximumBlockSize
The maximum number of samples that will be in the blocks sent to process() method.
Contains context information that is passed into an algorithm&#39;s process method.
const ConstAudioBlockType & getInputBlock() const noexcept
Returns the audio block to use as the input to a process function.
static constexpr bool usesSeparateInputAndOutputBlocks()
All process context classes will define this constant method so that templated code can determine whe...
Contains context information that is passed into an algorithm&#39;s process method.
ContextSampleType SampleType
The type of a single sample (which may be a vector if multichannel).
AudioBlockType & getOutputBlock() const noexcept
Returns the audio block to use as the output to a process function.
static constexpr bool usesSeparateInputAndOutputBlocks()
All process context classes will define this constant method so that templated code can determine whe...
This is a handy base class for the state of a processor (such as parameter values) which is typically...
This structure is passed into a DSP algorithm&#39;s prepare() method, and contains information about vari...
A smart-pointer class which points to a reference-counted object.
ProcessContextReplacing(AudioBlockType &block) noexcept
Creates a ProcessContextReplacing that uses the given audio block.
A base class which provides methods for reference-counting.
AudioBlockType & getOutputBlock() const noexcept
Returns the audio block to use as the output to a process function.