1 files changed, 94 insertions, 0 deletions
diff --git a/cmd/cmd_fir1p.c b/cmd/cmd_fir1p.c
new file mode 100644
index 0000000..b011719
--- /dev/null
+++ b/cmd/cmd_fir1p.c
@@ -0,0 +1,94 @@
+#include "cmd_fir1p.h"
+
+#define FIR_SIZE 12
+
+double fir_coef[FIR_SIZE] = 
+{
+ -0.0044384,  -0.0041841,   0.0130183,   0.0746628,   
+  0.1720210,   0.2489204,   0.2489204,   0.1720210,   
+  0.0746628,   0.0130183,  -0.0041841,  -0.0044384
+};
+
+#define MAX_INPUT_LEN 80
+#define BUFFER_LEN (FIR_SIZE-1+MAX_INPUT_LEN)
+double insamp[BUFFER_LEN];
+
+int fir1filter(double *coeffs, double *input, double *output,
+	int length, int filter_length)
+{
+	double acc;
+	double *coeffp;
+	double *inputp;
+	int n;
+	int k;
+
+	memcpy(&insamp[filter_length-1], input, length*sizeof(double));
+
+	for (n=0; n<length; n++)
+	{
+		coeffp = coeffs;
+		inputp = &insamp[filter_length - 1 + n];
+		acc = 0;
+
+		for (k=0;k<filter_length;k++)
+		{
+			acc += (*coeffp++)*(*inputp--);
+		}
+
+		output[n] = acc;
+	}
+
+	memmove(&insamp[0], &insamp[length], (filter_length-1)*sizeof(double));
+
+	return 0;
+}
+
+void *cmd_fir1p(void *data)
+{
+	char *ret = NULL;
+	int i=0,j=0;
+
+	if (data == NULL)
+	{
+		ret = alloc_new_str("FIR filter N=12\n");
+		return ret;
+	}
+
+	double input[MAX_INPUT_LEN];
+	double output[MAX_INPUT_LEN];
+
+	int count;
+	sds params = sdsnew(data);
+	sds out_result = sdsempty();
+	sds *tokens;
+	//printf("%s\n",params);
+	//tokens = sdssplitlen(params, sdslen(params), " ", 1, &count);
+	tokens = sdssplitargs(params, &count);
+
+	for (i=0;i<count;i++)
+	{
+		//printf("[%s]\n",tokens[i]);
+		input[i] = atof(tokens[i]);
+	}
+
+	fir1filter(fir_coef, input, output, count, FIR_SIZE);
+
+	for (i=0;i<count;i++)
+	{
+		//cut to max size 512
+		char str_double[16];
+		snprintf(str_double, 16, "%.3f ", output[i]);
+		out_result = sdscat(out_result, str_double);
+	}
+	out_result = sdscat(out_result,"\n");
+
+
+
+	ret = alloc_new_str(out_result);
+
+	sdsfree(params);
+	sdsfree(out_result);
+	sdsfreesplitres(tokens, count);
+
+	return ret;
+}
+\ No newline at end of file