Skip to content
Snippets Groups Projects
irc2pc.c 3.92 KiB
Newer Older
  • Learn to ignore specific revisions
  • Mark Spencer's avatar
    Mark Spencer committed
    /*
    
    $Log$
    
    Revision 1.15  2004/06/26 03:50:14  markster
    Merge source cleanups (bug #1911)
    
    
    Revision 1.14  2003/02/12 13:59:15  matteo
    mer feb 12 14:56:57 CET 2003
    
    Revision 1.1.1.1  2003/02/12 13:59:15  matteo
    mer feb 12 14:56:57 CET 2003
    
    Mark Spencer's avatar
    Mark Spencer committed
    
    Revision 1.2  2000/01/05 08:20:39  markster
    Some OSS fixes and a few lpc changes to make it actually work
    
     * Revision 1.1  1996/08/19  22:31:56  jaf
     * Initial revision
     *
    
    */
    
    /*  -- translated by f2c (version 19951025).
       You must link the resulting object file with the libraries:
    	-lf2c -lm   (in that order)
    */
    
    #include "f2c.h"
    
    
    #ifdef P_R_O_T_O_T_Y_P_E_S
    extern int irc2pc_(real *rc, real *pc, integer *order, real *gprime, real *g2pass);
    #endif
    
    
    Mark Spencer's avatar
    Mark Spencer committed
    /* ***************************************************************** */
    
    /* 	IRC2PC Version 48 */
    
    /* $Log$
    
     * Revision 1.15  2004/06/26 03:50:14  markster
     * Merge source cleanups (bug #1911)
    
    Mark Spencer's avatar
    Mark Spencer committed
     *
    
     * Revision 1.14  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.1.1.1  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.2  2000/01/05 08:20:39  markster
     * Some OSS fixes and a few lpc changes to make it actually work
     *
    
    Mark Spencer's avatar
    Mark Spencer committed
     * Revision 1.1  1996/08/19  22:31:56  jaf
     * Initial revision
     * */
    /* Revision 1.3  1996/03/20  15:47:19  jaf */
    /* Added comments about which indices of array arguments are read or */
    /* written. */
    
    /* Revision 1.2  1996/03/14  16:59:04  jaf */
    /* Comments added explaining that none of the local variables of this */
    /* subroutine need to be saved from one invocation to the next. */
    
    /* Revision 1.1  1996/02/07 14:47:27  jaf */
    /* Initial revision */
    
    
    /* ***************************************************************** */
    
    /*   Convert Reflection Coefficients to Predictor Coeficients */
    
    /* Inputs: */
    /*  RC     - Reflection coefficients */
    /*           Indices 1 through ORDER read. */
    /*  ORDER  - Number of RC's */
    /*  GPRIME - Excitation modification gain */
    /* Outputs: */
    /*  PC     - Predictor coefficients */
    /*           Indices 1 through ORDER written. */
    /*           Indices 1 through ORDER-1 are read after being written. */
    /*  G2PASS - Excitation modification sharpening factor */
    
    /* This subroutine has no local state. */
    
    /* Subroutine */ int irc2pc_(real *rc, real *pc, integer *order, real *gprime,
    	 real *g2pass)
    {
        /* System generated locals */
        integer i__1, i__2;
    
        /* Builtin functions */
        double sqrt(doublereal);
    
        /* Local variables */
        real temp[10];
        integer i__, j;
    
    /* 	Arguments */
    /* $Log$
    
     * Revision 1.15  2004/06/26 03:50:14  markster
     * Merge source cleanups (bug #1911)
    
    Mark Spencer's avatar
    Mark Spencer committed
     *
    
     * Revision 1.14  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.1.1.1  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.2  2000/01/05 08:20:39  markster
     * Some OSS fixes and a few lpc changes to make it actually work
     *
    
    Mark Spencer's avatar
    Mark Spencer committed
     * Revision 1.1  1996/08/19  22:31:56  jaf
     * Initial revision
     * */
    /* Revision 1.3  1996/03/29  22:03:47  jaf */
    /* Removed definitions for any constants that were no longer used. */
    
    /* Revision 1.2  1996/03/26  19:34:33  jaf */
    /* Added comments indicating which constants are not needed in an */
    /* application that uses the LPC-10 coder. */
    
    /* Revision 1.1  1996/02/07  14:43:51  jaf */
    /* Initial revision */
    
    /*   LPC Configuration parameters: */
    /* Frame size, Prediction order, Pitch period */
    /*       Local variables that need not be saved */
        /* Parameter adjustments */
        --pc;
        --rc;
    
        /* Function Body */
        *g2pass = 1.f;
        i__1 = *order;
        for (i__ = 1; i__ <= i__1; ++i__) {
    	*g2pass *= 1.f - rc[i__] * rc[i__];
        }
    
        *g2pass = *gprime * (real)sqrt(*g2pass);
    
    Mark Spencer's avatar
    Mark Spencer committed
        pc[1] = rc[1];
        i__1 = *order;
        for (i__ = 2; i__ <= i__1; ++i__) {
    	i__2 = i__ - 1;
    	for (j = 1; j <= i__2; ++j) {
    	    temp[j - 1] = pc[j] - rc[i__] * pc[i__ - j];
    	}
    	i__2 = i__ - 1;
    	for (j = 1; j <= i__2; ++j) {
    	    pc[j] = temp[j - 1];
    	}
    	pc[i__] = rc[i__];
        }
        return 0;
    } /* irc2pc_ */