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audio_mix.h
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1 /*
2  * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVRESAMPLE_AUDIO_MIX_H
22 #define AVRESAMPLE_AUDIO_MIX_H
23 
24 #include <stdint.h>
25 
26 #include "libavutil/samplefmt.h"
27 #include "avresample.h"
28 #include "internal.h"
29 #include "audio_data.h"
30 
31 typedef void (mix_func)(uint8_t **src, void **matrix, int len, int out_ch,
32  int in_ch);
33 
34 /**
35  * Set mixing function if the parameters match.
36  *
37  * This compares the parameters of the mixing function to the parameters in the
38  * AudioMix context. If the parameters do not match, no changes are made to the
39  * active functions. If the parameters do match and the alignment is not
40  * constrained, the function is set as the generic mixing function. If the
41  * parameters match and the alignment is constrained, the function is set as
42  * the optimized mixing function.
43  *
44  * @param am AudioMix context
45  * @param fmt input/output sample format
46  * @param coeff_type mixing coefficient type
47  * @param in_channels number of input channels, or 0 for any number of channels
48  * @param out_channels number of output channels, or 0 for any number of channels
49  * @param ptr_align buffer pointer alignment, in bytes
50  * @param samples_align buffer size alignment, in samples
51  * @param descr function type description (e.g. "C" or "SSE")
52  * @param mix_func mixing function pointer
53  */
55  enum AVMixCoeffType coeff_type, int in_channels,
56  int out_channels, int ptr_align, int samples_align,
57  const char *descr, void *mix_func);
58 
59 /**
60  * Allocate and initialize an AudioMix context.
61  *
62  * The parameters in the AVAudioResampleContext are used to initialize the
63  * AudioMix context.
64  *
65  * @param avr AVAudioResampleContext
66  * @return newly-allocated AudioMix context.
67  */
69 
70 /**
71  * Free an AudioMix context.
72  */
73 void ff_audio_mix_free(AudioMix **am);
74 
75 /**
76  * Apply channel mixing to audio data using the current mixing matrix.
77  */
78 int ff_audio_mix(AudioMix *am, AudioData *src);
79 
80 /**
81  * Get the current mixing matrix.
82  */
83 int ff_audio_mix_get_matrix(AudioMix *am, double *matrix, int stride);
84 
85 /**
86  * Set the current mixing matrix.
87  */
88 int ff_audio_mix_set_matrix(AudioMix *am, const double *matrix, int stride);
89 
90 /* arch-specific initialization functions */
91 
93 
94 #endif /* AVRESAMPLE_AUDIO_MIX_H */