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/*
 * This source code is a product of Sun Microsystems, Inc. and is provided
 * for unrestricted use.  Users may copy or modify this source code without
 * charge.
 *
 * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
 * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 *
 * Sun source code is provided with no support and without any obligation on
 * the part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 *
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
 * OR ANY PART THEREOF.
 *
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 *
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */

/*
 * g72x.h
 *
 * Header file for CCITT conversion routines.
 *
 */
#ifndef _G72X_H
#define	_G72X_H

#define	AUDIO_ENCODING_ULAW	(1)	/* ISDN u-law */
#define	AUDIO_ENCODING_ALAW	(2)	/* ISDN A-law */
#define	AUDIO_ENCODING_LINEAR	(3)	/* PCM 2's-complement (0-center) */

/*
 * The following is the definition of the state structure
 * used by the G.721/G.723 encoder and decoder to preserve their internal
 * state between successive calls.  The meanings of the majority
 * of the state structure fields are explained in detail in the
 * CCITT Recommendation G.721.  The field names are essentially indentical
 * to variable names in the bit level description of the coding algorithm
 * included in this Recommendation.
 */
struct g72x_state {
	long yl;	/* Locked or steady state step size multiplier. */
	short yu;	/* Unlocked or non-steady state step size multiplier. */
	short dms;	/* Short term energy estimate. */
	short dml;	/* Long term energy estimate. */
	short ap;	/* Linear weighting coefficient of 'yl' and 'yu'. */

	short a[2];	/* Coefficients of pole portion of prediction filter. */
	short b[6];	/* Coefficients of zero portion of prediction filter. */
	short pk[2];	/*
			 * Signs of previous two samples of a partially
			 * reconstructed signal.
			 */
	short dq[6];	/*
			 * Previous 6 samples of the quantized difference
			 * signal represented in an internal floating point
			 * format.
			 */
	short sr[2];	/*
			 * Previous 2 samples of the quantized difference
			 * signal represented in an internal floating point
			 * format.
			 */
	char td;	/* delayed tone detect, new in 1988 version */
};

/* External function definitions. */

extern void g72x_init_state(struct g72x_state *);
extern int predictor_zero(struct g72x_state *state_ptr);
extern int predictor_pole(struct g72x_state *state_ptr);
extern int step_size(struct g72x_state *state_ptr);

extern int quantize(
		int d,
		int y,
		short *table,
		int size);
extern int reconstruct(
		int sign,
		int dqln,
		int y);
extern void update(
		int code_size,
		int y,
		int wi,
		int fi,
		int dq,
		int sr,
		int dqsez,
		struct g72x_state *state_ptr);

extern int tandem_adjust_alaw(
		int sr,
		int se,
		int y,
		int i,
		int sign,
		short *qtab);
extern int tandem_adjust_ulaw(
		int sr,
		int se,
		int y,
		int i,
		int sign,
		short *qtab);

extern int g721_encoder(
		int sample,
		int in_coding,
		struct g72x_state *state_ptr);
extern int g721_decoder(
		int code,
		int out_coding,
		struct g72x_state *state_ptr);
extern int g723_24_encoder(
		int sample,
		int in_coding,
		struct g72x_state *state_ptr);
extern int g723_24_decoder(
		int code,
		int out_coding,
		struct g72x_state *state_ptr);
extern int g723_40_encoder(
		int sample,
		int in_coding,
		struct g72x_state *state_ptr);
extern int g723_40_decoder(
		int code,
		int out_coding,
		struct g72x_state *state_ptr);

extern unsigned char linear2alaw(int pcm_val);
extern int alaw2linear(unsigned char a_val);
extern unsigned char linear2ulaw(int pcm_val);
extern int ulaw2linear(unsigned char u_val);
extern unsigned char alaw2ulaw(unsigned char aval);
extern unsigned char ulaw2alaw(unsigned char uval);

#endif /* !_G72X_H */