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    /*
    
    $Log$
    
    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
    
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    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  22:31:35  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 lpfilt_(real *inbuf, real *lpbuf, integer *len, integer *nsamp);
    #endif
    
    
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    /* *********************************************************************** */
    
    /* 	LPFILT Version 55 */
    
    /* $Log$
    
     * Revision 1.15  2004/06/26 03:50:14  markster
     * Merge source cleanups (bug #1911)
    
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     *
    
     * 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
     *
    
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     * Revision 1.1  1996/08/19  22:31:35  jaf
     * Initial revision
     * */
    /* Revision 1.3  1996/03/15  16:53:49  jaf */
    /* Just put comment header in standard form. */
    
    /* Revision 1.2  1996/03/12  23:58:06  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 14:47:44  jaf */
    /* Initial revision */
    
    
    /* *********************************************************************** */
    
    /*   31 Point Equiripple FIR Low-Pass Filter */
    /*     Linear phase, delay = 15 samples */
    
    /* 	Passband:  ripple = 0.25 dB, cutoff =  800 Hz */
    /* 	Stopband:  atten. =  40. dB, cutoff = 1240 Hz */
    
    /* Inputs: */
    /*  LEN    - Length of speech buffers */
    /*  NSAMP  - Number of samples to filter */
    /*  INBUF  - Input speech buffer */
    /*           Indices len-nsamp-29 through len are read. */
    /* Output: */
    /*  LPBUF  - Low passed speech buffer (must be different array than INBUF) */
    /*           Indices len+1-nsamp through len are written. */
    
    /* This subroutine has no local state. */
    
    /* Subroutine */ int lpfilt_(real *inbuf, real *lpbuf, integer *len, integer *
    	nsamp)
    {
        /* System generated locals */
        integer i__1;
    
        /* Local variables */
        integer j;
        real t;
    
    /* 	Arguments */
    /* 	Parameters/constants */
    /*       Local variables that need not be saved */
    /*       Local state */
    /*       None */
        /* Parameter adjustments */
        --lpbuf;
        --inbuf;
    
        /* Function Body */
        i__1 = *len;
        for (j = *len + 1 - *nsamp; j <= i__1; ++j) {
    	t = (inbuf[j] + inbuf[j - 30]) * -.0097201988f;
    	t += (inbuf[j - 1] + inbuf[j - 29]) * -.0105179986f;
    	t += (inbuf[j - 2] + inbuf[j - 28]) * -.0083479648f;
    	t += (inbuf[j - 3] + inbuf[j - 27]) * 5.860774e-4f;
    	t += (inbuf[j - 4] + inbuf[j - 26]) * .0130892089f;
    	t += (inbuf[j - 5] + inbuf[j - 25]) * .0217052232f;
    	t += (inbuf[j - 6] + inbuf[j - 24]) * .0184161253f;
    	t += (inbuf[j - 7] + inbuf[j - 23]) * 3.39723e-4f;
    	t += (inbuf[j - 8] + inbuf[j - 22]) * -.0260797087f;
    	t += (inbuf[j - 9] + inbuf[j - 21]) * -.0455563702f;
    	t += (inbuf[j - 10] + inbuf[j - 20]) * -.040306855f;
    	t += (inbuf[j - 11] + inbuf[j - 19]) * 5.029835e-4f;
    	t += (inbuf[j - 12] + inbuf[j - 18]) * .0729262903f;
    	t += (inbuf[j - 13] + inbuf[j - 17]) * .1572008878f;
    	t += (inbuf[j - 14] + inbuf[j - 16]) * .2247288674f;
    	t += inbuf[j - 15] * .250535965f;
    	lpbuf[j] = t;
        }
        return 0;
    } /* lpfilt_ */