lavr: define ResampleContext in resample.h
[libav.git] / libavresample / resample.h
1 /*
2 * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
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_RESAMPLE_H
22 #define AVRESAMPLE_RESAMPLE_H
23
24 #include "avresample.h"
25 #include "internal.h"
26 #include "audio_data.h"
27
28 struct ResampleContext {
29 AVAudioResampleContext *avr;
30 AudioData *buffer;
31 uint8_t *filter_bank;
32 int filter_length;
33 int ideal_dst_incr;
34 int dst_incr;
35 unsigned int index;
36 int frac;
37 int src_incr;
38 int compensation_distance;
39 int phase_shift;
40 int phase_mask;
41 int linear;
42 enum AVResampleFilterType filter_type;
43 int kaiser_beta;
44 void (*set_filter)(void *filter, double *tab, int phase, int tap_count);
45 void (*resample_one)(struct ResampleContext *c, void *dst0,
46 int dst_index, const void *src0,
47 unsigned int index, int frac);
48 void (*resample_nearest)(void *dst0, int dst_index,
49 const void *src0, unsigned int index);
50 int padding_size;
51 int initial_padding_filled;
52 int initial_padding_samples;
53 int final_padding_filled;
54 int final_padding_samples;
55 };
56
57 /**
58 * Allocate and initialize a ResampleContext.
59 *
60 * The parameters in the AVAudioResampleContext are used to initialize the
61 * ResampleContext.
62 *
63 * @param avr AVAudioResampleContext
64 * @return newly-allocated ResampleContext
65 */
66 ResampleContext *ff_audio_resample_init(AVAudioResampleContext *avr);
67
68 /**
69 * Free a ResampleContext.
70 *
71 * @param c ResampleContext
72 */
73 void ff_audio_resample_free(ResampleContext **c);
74
75 /**
76 * Resample audio data.
77 *
78 * Changes the sample rate.
79 *
80 * @par
81 * All samples in the source data may not be consumed depending on the
82 * resampling parameters and the size of the output buffer. The unconsumed
83 * samples are automatically added to the start of the source in the next call.
84 * If the destination data can be reallocated, that may be done in this function
85 * in order to fit all available output. If it cannot be reallocated, fewer
86 * input samples will be consumed in order to have the output fit in the
87 * destination data buffers.
88 *
89 * @param c ResampleContext
90 * @param dst destination audio data
91 * @param src source audio data
92 * @return 0 on success, negative AVERROR code on failure
93 */
94 int ff_audio_resample(ResampleContext *c, AudioData *dst, AudioData *src);
95
96 #endif /* AVRESAMPLE_RESAMPLE_H */