/*

** 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) ;