ref: 7592cc985f084dbfab7f941100d1f09b33a43e22
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 */