libsndfile source files.
[Faustine.git] / interpretor / libsndfile-1.0.25 / src / ima_oki_adpcm.h
1 /*
2 ** Copyright (C) 2007-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
3 ** Copyright (c) 2007 <robs@users.sourceforge.net>
4 **
5 ** This library is free software; you can redistribute it and/or modify it
6 ** under the terms of the GNU Lesser General Public License as published by
7 ** the Free Software Foundation; either version 2 of the License, or (at
8 ** your option) any later version.
9 **
10 ** This library is distributed in the hope that it will be useful, but
11 ** WITHOUT ANY WARRANTY; without even the implied warranty of
12 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
13 ** General Public License for more details.
14 **
15 ** You should have received a copy of the GNU Lesser General Public License
16 ** along with this library. If not, write to the Free Software Foundation,
17 ** Fifth Floor, 51 Franklin Street, Boston, MA 02111-1301, USA.
18 */
19
20 /* ADPCM: IMA, OKI <==> 16-bit PCM. */
21
22
23 #define IMA_OKI_ADPCM_CODE_LEN 256
24 #define IMA_OKI_ADPCM_PCM_LEN (IMA_OKI_ADPCM_CODE_LEN *2)
25
26 typedef struct
27 {
28 /* private: */
29 int mask ;
30 int last_output ;
31 int step_index ;
32 int max_step_index ;
33 int const * steps ;
34
35 /* public: */
36 int errors ;
37 int code_count, pcm_count ;
38
39 unsigned char codes [IMA_OKI_ADPCM_CODE_LEN] ;
40 short pcm [IMA_OKI_ADPCM_PCM_LEN] ;
41 } IMA_OKI_ADPCM ;
42
43 typedef enum
44 { IMA_OKI_ADPCM_TYPE_IMA,
45 IMA_OKI_ADPCM_TYPE_OKI
46 } IMA_OKI_ADPCM_TYPE ;
47
48 void ima_oki_adpcm_init (IMA_OKI_ADPCM * state, IMA_OKI_ADPCM_TYPE type) ;
49
50 int adpcm_decode (IMA_OKI_ADPCM * state, int /* 0..15 */ code) ;
51 int adpcm_encode (IMA_OKI_ADPCM * state, int /* -32768..32767 */ sample) ;
52
53 void ima_oki_adpcm_decode_block (IMA_OKI_ADPCM * state) ;
54 void ima_oki_adpcm_encode_block (IMA_OKI_ADPCM * state) ;