ref: defc721f401790c220e785f7c0746bc37ea5b971
dir: /common/libsndfile/src/G72x/private.h/
/*
* 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
*/
#ifndef G72X_PRIVATE_H
#define G72X_PRIVATE_H
/*
** 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 identical to variable names
** in the bit level description of the coding algorithm included in this
** Recommendation.
*/
typedef struct private_g72x
{ 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 */
/* The following struct members were added for libsndfile. The original
** code worked by calling a set of functions on a sample by sample basis
** which is slow on architectures like Intel x86. For libsndfile, this
** was changed so that the encoding and decoding routines could work on
** a block of samples at a time to reduce the function call overhead.
*/
int (*encoder) (int, struct private_g72x* state) ;
int (*decoder) (int, struct private_g72x* state) ;
int codec_bits ;
int byte_index, sample_index ;
} G72x_STATE ;
int predictor_zero(G72x_STATE *state_ptr);
int predictor_pole(G72x_STATE *state_ptr);
int step_size(G72x_STATE *state_ptr);
int quantize(int d, int y, short *table, int size);
int reconstruct(int sign, int dqln, int y);
void update (int code_size, int y, int wi, int fi, int dq, int sr, int dqsez, G72x_STATE *state_ptr);
int g721_encoder (int sample, G72x_STATE *state_ptr);
int g721_decoder (int code, G72x_STATE *state_ptr);
int g723_16_encoder (int sample, G72x_STATE *state_ptr);
int g723_16_decoder (int code, G72x_STATE *state_ptr);
int g723_24_encoder (int sample, G72x_STATE *state_ptr);
int g723_24_decoder (int code, G72x_STATE *state_ptr);
int g723_40_encoder (int sample, G72x_STATE *state_ptr);
int g723_40_decoder (int code, G72x_STATE *state_ptr);
#endif /* G72X_PRIVATE_H */