inithann.c

dsPIC30F_DSP算法库

/*********************************************************************
*                                                                    *
*                       Software License Agreement                   *
*                                                                    *
*   The software supplied herewith by Microchip Technology           *
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*   THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION.  NO           *
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*********************************************************************/

/* Local headers. */
#include "dsp.h"				/* DSP Library interface */

/*...........................................................................*/


extern fractional* HanningInit (	/* Initialize a Hanning window */
					/* computed in floating point */
					/* converted to fractionals */
   int numElems,			/* number elements in window */
   fractional* window			/* ptr to window */
					/* window returned */
) {

   /* Local declarations. */
   fractional* retWindow = window;
   double arg = 2.0*PI/((double) (numElems-1));
   int cntr = 0;

   /* Compute window factors. */
   for (cntr = 0; cntr < numElems; cntr++) {
      *(window++) = Float2Fract (HANN_0 + HANN_1*cos(arg*cntr));
   }

   /* Return window pointer. */
   return (retWindow);

} /* end of HanningInit */

/*...........................................................................*/

/***************************************************************************/
/* EOF */