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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 13:59:14  matteo
    mer feb 12 14:56:57 CET 2003
    
    Revision 1.1.1.1  2003/02/12 13:59:14  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 1.2  1996/08/20  20:23:46  jaf
     * Removed all static local variables that were SAVE'd in the Fortran
     * code, and put them in struct lpc10_decoder_state that is passed as an
     * argument.
     *
     * Removed init function, since all initialization is now done in
     * init_lpc10_decoder_state().
     *
     * Revision 1.1  1996/08/19  22:32:34  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 deemp_(real *x, integer *n, struct lpc10_decoder_state *st);
    #endif
    
    
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    /* ***************************************************************** */
    
    /* 	DEEMP Version 48 */
    
    /* $Log$
    
     * 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 13:59:14  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.1.1.1  2003/02/12 13:59:14  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 1.2  1996/08/20  20:23:46  jaf
     * Removed all static local variables that were SAVE'd in the Fortran
     * code, and put them in struct lpc10_decoder_state that is passed as an
     * argument.
     *
     * Removed init function, since all initialization is now done in
     * init_lpc10_decoder_state().
     *
     * Revision 1.1  1996/08/19  22:32:34  jaf
     * Initial revision
     * */
    /* Revision 1.3  1996/03/20  15:54:37  jaf */
    /* Added comments about which indices of array arguments are read or */
    /* written. */
    
    /* Added entry INITDEEMP to reinitialize the local state variables, if */
    /* desired. */
    
    /* Revision 1.2  1996/03/14  22:11:13  jaf */
    /* Comments added explaining which of the local variables of this */
    /* subroutine need to be saved from one invocation to the next, and which */
    /* do not. */
    
    /* Revision 1.1  1996/02/07 14:44:53  jaf */
    /* Initial revision */
    
    
    /* ***************************************************************** */
    
    /*  De-Emphasize output speech with   1 / ( 1 - .75z**-1 ) */
    /*    cascaded with 200 Hz high pass filter */
    /*    ( 1 - 1.9998z**-1 + z**-2 ) / ( 1 - 1.75z**-1 + .78z**-2 ) */
    
    /*  WARNING!  The coefficients above may be out of date with the code */
    /*  below.  Either that, or some kind of transformation was performed */
    /*  on the coefficients above to create the code below. */
    
    /* Input: */
    /*  N  - Number of samples */
    /* Input/Output: */
    /*  X  - Speech */
    /*       Indices 1 through N are read before being written. */
    
    /* This subroutine maintains local state from one call to the next.  If */
    /* you want to switch to using a new audio stream for this filter, or */
    /* reinitialize its state for any other reason, call the ENTRY */
    /* INITDEEMP. */
    
    /* Subroutine */ int deemp_(real *x, integer *n, struct lpc10_decoder_state *st)
    {
        /* Initialized data */
    
        real *dei1;
        real *dei2;
        real *deo1;
        real *deo2;
        real *deo3;
    
        /* System generated locals */
        integer i__1;
        real r__1;
    
        /* Local variables */
        integer k;
        real dei0;
    
    /*       Arguments */
    /*       Local variables that need not be saved */
    /*       Local state */
    /*       All of the locals saved below were not given explicit initial */
    /*       values in the original code.  I think 0 is a safe choice. */
        /* Parameter adjustments */
        if (x) {
    	--x;
    	}
    
        /* Function Body */
    
        dei1 = &(st->dei1);
        dei2 = &(st->dei2);
        deo1 = &(st->deo1);
        deo2 = &(st->deo2);
        deo3 = &(st->deo3);
    
        i__1 = *n;
        for (k = 1; k <= i__1; ++k) {
    	dei0 = x[k];
    	r__1 = x[k] - *dei1 * 1.9998f + *dei2;
    	x[k] = r__1 + *deo1 * 2.5f - *deo2 * 2.0925f + *deo3 * .585f;
    	*dei2 = *dei1;
    	*dei1 = dei0;
    	*deo3 = *deo2;
    	*deo2 = *deo1;
    	*deo1 = x[k];
        }
        return 0;
    } /* deemp_ */