mathhalf.h

2400bps MELP语音编解码源程序。

/*

2.4 kbps MELP Proposed Federal Standard speech coder

Fixed-point C code, version 1.0

Copyright (c) 1998, Texas Instruments, Inc.  

Texas Instruments has intellectual property rights on the MELP
algorithm.  The Texas Instruments contact for licensing issues for
commercial and non-government use is William Gordon, Director,
Government Contracts, Texas Instruments Incorporated, Semiconductor
Group (phone [phone]).

The fixed-point version of the voice codec Mixed Excitation Linear
Prediction (MELP) is based on specifications on the C-language software
simulation contained in GSM 06.06 which is protected by copyright and
is the property of the European Telecommunications Standards Institute
(ETSI). This standard is available from the ETSI publication office
tel. [phone]. ETSI has granted a license to United States
Department of Defense to use the C-language software simulation contained
in GSM 06.06 for the purposes of the development of a fixed-point
version of the voice codec Mixed Excitation Linear Prediction (MELP).
Requests for authorization to make other use of the GSM 06.06 or
otherwise distribute or modify them need to be addressed to the ETSI
Secretariat fax: [phone].

*/
#include "typedefs.h"

#ifndef __MATHHALF
#define __MATHHALF

/* addition */
/************/

Shortword add(Shortword var1, Shortword var2);  /* 1 ops */
Shortword sub(Shortword var1, Shortword var2);  /* 1 ops */
Longword L_add(Longword L_var1, Longword L_var2);       /* 2 ops */
Longword L_sub(Longword L_var1, Longword L_var2);       /* 2 ops */

/* multiplication */
/******************/

Shortword mult(Shortword var1, Shortword var2); /* 1 ops */
Longword L_mult(Shortword var1, Shortword var2);        /* 1 ops */
Shortword mult_r(Shortword var1, Shortword var2);       /* 2 ops */


/* arithmetic shifts */
/*********************/

Shortword shr(Shortword var1, Shortword var2);  /* 1 ops */
Shortword shl(Shortword var1, Shortword var2);  /* 1 ops */
Longword L_shr(Longword L_var1, Shortword var2);        /* 2 ops */
Longword L_shl(Longword L_var1, Shortword var2);        /* 2 ops */
Shortword shift_r(Shortword var, Shortword var2);       /* 2 ops */
Longword L_shift_r(Longword L_var, Shortword var2);     /* 3 ops */

/* absolute value  */
/*******************/

Shortword abs_s(Shortword var1);       /* 1 ops */
Longword L_abs(Longword var1);         /* 3 ops */


/* multiply accumulate  */
/************************/

Longword L_mac(Longword L_var3,
                      Shortword var1, Shortword var2);  /* 1 op */
Shortword mac_r(Longword L_var3,
                       Shortword var1, Shortword var2); /* 2 op */
Longword L_msu(Longword L_var3,
                      Shortword var1, Shortword var2);  /* 1 op */
Shortword msu_r(Longword L_var3,
                       Shortword var1, Shortword var2); /* 2 op */


/* negation  */
/*************/

Shortword negate(Shortword var1);      /* 1 ops */
Longword L_negate(Longword L_var1);    /* 2 ops */


/* Accumulator manipulation */
/****************************/

Longword L_deposit_l(Shortword var1);  /* 1 ops */
Longword L_deposit_h(Shortword var1);  /* 1 ops */
Shortword extract_l(Longword L_var1);  /* 1 ops */
Shortword extract_h(Longword L_var1);  /* 1 ops */

/* Round */
/*********/

Shortword round(Longword L_var1);      /* 1 ops */

/* Normalization */
/*****************/

Shortword norm_l(Longword L_var1);     /* 30 ops */
Shortword norm_s(Shortword var1);      /* 15 ops */

/* Division */
/************/
Shortword divide_s(Shortword var1, Shortword var2);     /* 18 ops */

/* Non-saturating instructions */
/*******************************/
Longword L_add_c(Longword L_Var1, Longword L_Var2);     /* 2 ops */
Longword L_sub_c(Longword L_Var1, Longword L_Var2);     /* 2 ops */
Longword L_sat(Longword L_var1);       /* 4 ops */
Longword L_macNs(Longword L_var3,
                        Shortword var1, Shortword var2);        /* 1 ops */
Longword L_msuNs(Longword L_var3,
                        Shortword var1, Shortword var2);        /* 1 ops */

#endif