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/*
** Copyright (C) 2007-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
** Copyright (c) 2007 <robs@users.sourceforge.net>
**
** This library is free software; you can redistribute it and/or modify it
** under the terms of the GNU Lesser General Public License as published by
** the Free Software Foundation; either version 2 of the License, or (at
** your option) any later version.
**
** This library is distributed in the hope that it will be useful, but
** WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
** General Public License for more details.
**
** You should have received a copy of the GNU Lesser General Public License
** along with this library. If not, write to the Free Software Foundation,
** Fifth Floor, 51 Franklin Street, Boston, MA 02111-1301, USA.
*/
/* ADPCM: IMA, OKI <==> 16-bit PCM. */
#define IMA_OKI_ADPCM_CODE_LEN 256
#define IMA_OKI_ADPCM_PCM_LEN (IMA_OKI_ADPCM_CODE_LEN *2)
typedef struct
{
/* private: */
int mask ;
int last_output ;
int step_index ;
int max_step_index ;
int const * steps ;
/* public: */
int errors ;
int code_count, pcm_count ;
unsigned char codes [IMA_OKI_ADPCM_CODE_LEN] ;
short pcm [IMA_OKI_ADPCM_PCM_LEN] ;
} IMA_OKI_ADPCM ;
typedef enum
{ IMA_OKI_ADPCM_TYPE_IMA,
IMA_OKI_ADPCM_TYPE_OKI
} IMA_OKI_ADPCM_TYPE ;
void ima_oki_adpcm_init (IMA_OKI_ADPCM * state, IMA_OKI_ADPCM_TYPE type) ;
int adpcm_decode (IMA_OKI_ADPCM * state, int /* 0..15 */ code) ;
int adpcm_encode (IMA_OKI_ADPCM * state, int /* -32768..32767 */ sample) ;
void ima_oki_adpcm_decode_block (IMA_OKI_ADPCM * state) ;
void ima_oki_adpcm_encode_block (IMA_OKI_ADPCM * state) ;
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