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1 : ////////////////////////////////////////////////////////////////////////////////
2 : ///
3 : /// A buffer class for temporarily storaging sound samples, operates as a
4 : /// first-in-first-out pipe.
5 : ///
6 : /// Samples are added to the end of the sample buffer with the 'putSamples'
7 : /// function, and are received from the beginning of the buffer by calling
8 : /// the 'receiveSamples' function. The class automatically removes the
9 : /// output samples from the buffer as well as grows the storage size
10 : /// whenever necessary.
11 : ///
12 : /// Author : Copyright (c) Olli Parviainen
13 : /// Author e-mail : oparviai 'at' iki.fi
14 : /// SoundTouch WWW: http://www.surina.net/soundtouch
15 : ///
16 : ////////////////////////////////////////////////////////////////////////////////
17 : //
18 : // Last changed : $Date: 2014-01-05 21:40:22 +0000 (Sun, 05 Jan 2014) $
19 : // File revision : $Revision: 4 $
20 : //
21 : // $Id: FIFOSampleBuffer.h 177 2014-01-05 21:40:22Z oparviai $
22 : //
23 : ////////////////////////////////////////////////////////////////////////////////
24 : //
25 : // License :
26 : //
27 : // SoundTouch audio processing library
28 : // Copyright (c) Olli Parviainen
29 : //
30 : // This library is free software; you can redistribute it and/or
31 : // modify it under the terms of the GNU Lesser General Public
32 : // License as published by the Free Software Foundation; either
33 : // version 2.1 of the License, or (at your option) any later version.
34 : //
35 : // This library is distributed in the hope that it will be useful,
36 : // but WITHOUT ANY WARRANTY; without even the implied warranty of
37 : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
38 : // Lesser General Public License for more details.
39 : //
40 : // You should have received a copy of the GNU Lesser General Public
41 : // License along with this library; if not, write to the Free Software
42 : // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
43 : //
44 : ////////////////////////////////////////////////////////////////////////////////
45 :
46 : #ifndef FIFOSampleBuffer_H
47 : #define FIFOSampleBuffer_H
48 :
49 : #include "FIFOSamplePipe.h"
50 :
51 : namespace soundtouch
52 : {
53 :
54 : /// Sample buffer working in FIFO (first-in-first-out) principle. The class takes
55 : /// care of storage size adjustment and data moving during input/output operations.
56 : ///
57 : /// Notice that in case of stereo audio, one sample is considered to consist of
58 : /// both channel data.
59 : class FIFOSampleBuffer : public FIFOSamplePipe
60 : {
61 : private:
62 : /// Sample buffer.
63 : SAMPLETYPE *buffer;
64 :
65 : // Raw unaligned buffer memory. 'buffer' is made aligned by pointing it to first
66 : // 16-byte aligned location of this buffer
67 : SAMPLETYPE *bufferUnaligned;
68 :
69 : /// Sample buffer size in bytes
70 : uint sizeInBytes;
71 :
72 : /// How many samples are currently in buffer.
73 : uint samplesInBuffer;
74 :
75 : /// Channels, 1=mono, 2=stereo.
76 : uint channels;
77 :
78 : /// Current position pointer to the buffer. This pointer is increased when samples are
79 : /// removed from the pipe so that it's necessary to actually rewind buffer (move data)
80 : /// only new data when is put to the pipe.
81 : uint bufferPos;
82 :
83 : /// Rewind the buffer by moving data from position pointed by 'bufferPos' to real
84 : /// beginning of the buffer.
85 : void rewind();
86 :
87 : /// Ensures that the buffer has capacity for at least this many samples.
88 : void ensureCapacity(uint capacityRequirement);
89 :
90 : /// Returns current capacity.
91 : uint getCapacity() const;
92 :
93 : public:
94 :
95 : /// Constructor
96 : FIFOSampleBuffer(int numChannels = 2 ///< Number of channels, 1=mono, 2=stereo.
97 : ///< Default is stereo.
98 : );
99 :
100 : /// destructor
101 : ~FIFOSampleBuffer();
102 :
103 : /// Returns a pointer to the beginning of the output samples.
104 : /// This function is provided for accessing the output samples directly.
105 : /// Please be careful for not to corrupt the book-keeping!
106 : ///
107 : /// When using this function to output samples, also remember to 'remove' the
108 : /// output samples from the buffer by calling the
109 : /// 'receiveSamples(numSamples)' function
110 : virtual SAMPLETYPE *ptrBegin();
111 :
112 : /// Returns a pointer to the end of the used part of the sample buffer (i.e.
113 : /// where the new samples are to be inserted). This function may be used for
114 : /// inserting new samples into the sample buffer directly. Please be careful
115 : /// not corrupt the book-keeping!
116 : ///
117 : /// When using this function as means for inserting new samples, also remember
118 : /// to increase the sample count afterwards, by calling the
119 : /// 'putSamples(numSamples)' function.
120 : SAMPLETYPE *ptrEnd(
121 : uint slackCapacity ///< How much free capacity (in samples) there _at least_
122 : ///< should be so that the caller can succesfully insert the
123 : ///< desired samples to the buffer. If necessary, the function
124 : ///< grows the buffer size to comply with this requirement.
125 : );
126 :
127 : /// Adds 'numSamples' pcs of samples from the 'samples' memory position to
128 : /// the sample buffer.
129 : virtual void putSamples(const SAMPLETYPE *samples, ///< Pointer to samples.
130 : uint numSamples ///< Number of samples to insert.
131 : );
132 :
133 : /// Adjusts the book-keeping to increase number of samples in the buffer without
134 : /// copying any actual samples.
135 : ///
136 : /// This function is used to update the number of samples in the sample buffer
137 : /// when accessing the buffer directly with 'ptrEnd' function. Please be
138 : /// careful though!
139 : virtual void putSamples(uint numSamples ///< Number of samples been inserted.
140 : );
141 :
142 : /// Output samples from beginning of the sample buffer. Copies requested samples to
143 : /// output buffer and removes them from the sample buffer. If there are less than
144 : /// 'numsample' samples in the buffer, returns all that available.
145 : ///
146 : /// \return Number of samples returned.
147 : virtual uint receiveSamples(SAMPLETYPE *output, ///< Buffer where to copy output samples.
148 : uint maxSamples ///< How many samples to receive at max.
149 : );
150 :
151 : /// Adjusts book-keeping so that given number of samples are removed from beginning of the
152 : /// sample buffer without copying them anywhere.
153 : ///
154 : /// Used to reduce the number of samples in the buffer when accessing the sample buffer directly
155 : /// with 'ptrBegin' function.
156 : virtual uint receiveSamples(uint maxSamples ///< Remove this many samples from the beginning of pipe.
157 : );
158 :
159 : /// Returns number of samples currently available.
160 : virtual uint numSamples() const;
161 :
162 : /// Sets number of channels, 1 = mono, 2 = stereo.
163 : void setChannels(int numChannels);
164 :
165 : /// Get number of channels
166 0 : int getChannels()
167 : {
168 0 : return channels;
169 : }
170 :
171 : /// Returns nonzero if there aren't any samples available for outputting.
172 : virtual int isEmpty() const;
173 :
174 : /// Clears all the samples.
175 : virtual void clear();
176 :
177 : /// allow trimming (downwards) amount of samples in pipeline.
178 : /// Returns adjusted amount of samples
179 : uint adjustAmountOfSamples(uint numSamples);
180 : };
181 :
182 : }
183 :
184 : #endif
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