pinebuds/services/multimedia/speech/inc/g72x.h

113 lines
3.4 KiB
C

/*
* 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.
*
*/
#include "math.h"
#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.
*/
typedef struct g726_state_s {
long yl; /* Locked or steady state step size multiplier. */
int yu; /* Unlocked or non-steady state step size multiplier. */
int dms; /* Short term energy estimate. */
int dml; /* Long term energy estimate. */
int ap; /* Linear weighting coefficient of 'yl' and 'yu'. */
int a[2]; /* Coefficients of pole portion of prediction filter. */
int b[6]; /* Coefficients of zero portion of prediction filter. */
int pk[2]; /* Signs of previous two samples of a partially
* reconstructed signal. */
short dq[6];/* int here fails in newupdate on encode!
* Previous 6 samples of the quantized difference
* signal represented in an internal floating point
* format.
*/
int sr[2]; /* Previous 2 samples of the quantized difference
* signal represented in an internal floating point
* format. */
int td; /* delayed tone detect, new in 1988 version */
} g726_state;
/* External function definitions. */
void g726_init_state( g726_state *);
int g726_32_encoder(
int sample,
int in_coding,
g726_state *state_ptr);
int g726_32_decoder(
int code,
int out_coding,
g726_state *state_ptr);
int g726_16_encoder(
int sample,
int in_coding,
g726_state *state_ptr);
int g726_16_decoder(
int code,
int out_coding,
g726_state *state_ptr);
int g726_24_encoder(
int sample,
int in_coding,
g726_state *state_ptr);
int g726_24_decoder(
int code,
int out_coding,
g726_state *state_ptr);
int g726_40_encoder(
int sample,
int in_coding,
g726_state *state_ptr);
int g726_40_decoder(
int code,
int out_coding,
g726_state *state_ptr);
#endif /* !_G72X_H */