Initial import

git-svn-id: http://moon:8086/svn/software/trunk/libsrc/fir@1 b431acfa-c32f-4a4a-93f1-934dc6c82436

firdecim.c

@@ -0,0 +1,77 @@
+/*************************************************************************/
+/* fir.c
+/*************************************************************************/
+#include <stdio.h>
+#include <malloc.h>
+#include "math.h"
+#include "fir.h"
+#include "firdecim.h"
+
+/*************************************************************************/
+/* Global Variables
+/*************************************************************************/
+int FDfilter(struct _sFIRDECIM *pObj, float *pX, float *pY, int len)
+{
+	int len2, i, firLen, kL;
+	float *pSxt, *pBt, sum;
+
+	kL = pObj->kL;
+	firLen = pObj->firLen;
+
+	pBt  = &pObj->pB[0];
+	pSxt = &pObj->pX[0];
+	len2 = 0;
+	while (len >= kL)
+	{
+
+        for (i = firLen-1; i >= kL; i--)
+		{
+            pObj->pX[i] = pObj->pX[i- kL];
+        }
+
+        for (i = kL-1; i >= 0; i--)
+		{
+			pObj->pX[i] = *(pX++);
+        }
+		len -= kL;
+		
+		sum = 0.0;
+
+		for (i=0; i < firLen; i++)
+			sum += pObj->pX[i] * pObj->pB[i];
+
+		*(pY++) = sum;
+		len2++;
+	}
+	return len2;
+}
+
+void FDinit(struct _sFIRDECIM *pObj, int kL, int nCoefPerPhase)
+{
+	int n;
+	pObj->kL = kL;
+
+	pObj->firLen = kL*nCoefPerPhase;
+	pObj->nCoefPerPhase = nCoefPerPhase;
+
+	if ((pObj->firLen%2) == 0)
+		pObj->firLen++;
+
+	pObj->pB = (float*)malloc(pObj->firLen*sizeof(float));
+	pObj->pX = (float*)malloc(pObj->firLen*sizeof(float));
+
+
+	for(n=0; n < pObj->firLen; n++)
+	{
+		pObj->pX[n] = 0;
+	}
+
+	Sinc(pObj->pB, kL, 1.f/kL, 1.f/kL, pObj->firLen);
+
+}
+
+void FDfree(struct _sFIRDECIM *pObj)
+{
+	free(pObj->pB);
+	free(pObj->pX);
+}