*/
/**
- * @file libavcodec/iirfilter.c
+ * @file
* different IIR filters implementation
*/
/// maximum supported filter order
#define MAXORDER 30
-struct FFIIRFilterCoeffs* ff_iir_filter_init_coeffs(enum IIRFilterType filt_type,
+av_cold struct FFIIRFilterCoeffs* ff_iir_filter_init_coeffs(enum IIRFilterType filt_type,
enum IIRFilterMode filt_mode,
int order, float cutoff_ratio,
float stopband, float ripple)
{
- int i, j, size;
+ int i, j;
FFIIRFilterCoeffs *c;
double wa;
double p[MAXORDER + 1][2];
return c;
}
-struct FFIIRFilterState* ff_iir_filter_init_state(int order)
+av_cold struct FFIIRFilterState* ff_iir_filter_init_state(int order)
{
FFIIRFilterState* s = av_mallocz(sizeof(FFIIRFilterState) + sizeof(s->x[0]) * (order - 1));
return s;
}
}
-void ff_iir_filter_free_state(struct FFIIRFilterState *state)
+av_cold void ff_iir_filter_free_state(struct FFIIRFilterState *state)
{
av_free(state);
}
-void ff_iir_filter_free_coeffs(struct FFIIRFilterCoeffs *coeffs)
+av_cold void ff_iir_filter_free_coeffs(struct FFIIRFilterCoeffs *coeffs)
{
if(coeffs){
av_free(coeffs->cx);
av_free(coeffs);
}
+#ifdef TEST
+#define FILT_ORDER 4
+#define SIZE 1024
+int main(void)
+{
+ struct FFIIRFilterCoeffs *fcoeffs = NULL;
+ struct FFIIRFilterState *fstate = NULL;
+ float cutoff_coeff = 0.4;
+ int16_t x[SIZE], y[SIZE];
+ int i;
+ FILE* fd;
+
+ fcoeffs = ff_iir_filter_init_coeffs(FF_FILTER_TYPE_BUTTERWORTH,
+ FF_FILTER_MODE_LOWPASS, FILT_ORDER,
+ cutoff_coeff, 0.0, 0.0);
+ fstate = ff_iir_filter_init_state(FILT_ORDER);
+
+ for (i = 0; i < SIZE; i++) {
+ x[i] = lrint(0.75 * INT16_MAX * sin(0.5*M_PI*i*i/SIZE));
+ }
+
+ ff_iir_filter(fcoeffs, fstate, SIZE, x, 1, y, 1);
+
+ fd = fopen("in.bin", "w");
+ fwrite(x, sizeof(x[0]), SIZE, fd);
+ fclose(fd);
+
+ fd = fopen("out.bin", "w");
+ fwrite(y, sizeof(y[0]), SIZE, fd);
+ fclose(fd);
+
+ ff_iir_filter_free_coeffs(fcoeffs);
+ ff_iir_filter_free_state(fstate);
+ return 0;
+}
+#endif /* TEST */