FFmpeg
adx.h
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1 /*
2  * ADX ADPCM codecs
3  * Copyright (c) 2001,2003 BERO
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * SEGA CRI adx codecs.
25  *
26  * Reference documents:
27  * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html
28  * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/
29  */
30 
31 #ifndef AVCODEC_ADX_H
32 #define AVCODEC_ADX_H
33 
34 typedef struct ADXChannelState {
35  int s1,s2;
37 
38 #define MAX_CHANNELS 6
39 
40 typedef struct ADXContext {
41  int channels;
44  int eof;
45  int cutoff;
46  int coeff[2];
47 } ADXContext;
48 
49 #define COEFF_BITS 12
50 
51 #define BLOCK_SIZE 18
52 #define BLOCK_SAMPLES 32
53 
54 /**
55  * Calculate LPC coefficients based on cutoff frequency and sample rate.
56  *
57  * @param cutoff cutoff frequency
58  * @param sample_rate sample rate
59  * @param bits number of bits used to quantize coefficients
60  * @param[out] coeff 2 quantized LPC coefficients
61  */
62 void ff_adx_calculate_coeffs(int cutoff, int sample_rate, int bits, int *coeff);
63 
64 #endif /* AVCODEC_ADX_H */
ADXContext::header_parsed
int header_parsed
Definition: adx.h:43
ADXChannelState::s2
int s2
Definition: adx.h:35
MAX_CHANNELS
#define MAX_CHANNELS
Definition: adx.h:38
ADXChannelState::s1
int s1
Definition: adx.h:35
sample_rate
sample_rate
Definition: ffmpeg_filter.c:424
ADXContext::eof
int eof
Definition: adx.h:44
ADXContext::cutoff
int cutoff
Definition: adx.h:45
bits
uint8_t bits
Definition: vp3data.h:128
ADXContext::channels
int channels
Definition: adx.h:41
ADXChannelState
Definition: adx.h:34
ADXContext::coeff
int coeff[2]
Definition: adx.h:46
ff_adx_calculate_coeffs
void ff_adx_calculate_coeffs(int cutoff, int sample_rate, int bits, int *coeff)
Calculate LPC coefficients based on cutoff frequency and sample rate.
Definition: adx.c:25
ADXContext
Definition: adx.h:40
ADXContext::prev
ADXChannelState prev[MAX_CHANNELS]
Definition: adx.h:42
coeff
static const double coeff[2][5]
Definition: vf_owdenoise.c:79