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/*
* Note: this currently doesn't get installed. There's also no way to query
* the location of wt.h. Conclusion: there is no C API.
*/
#include <stdio.h>
#include "wt.h"
int main(){
// Using C API to decompose 1D signal.
// Results equivalent to pywt.dwt([1,2,3,4,5,6,7,8], 'db2', 'zpd').
// Compile: gcc -I../src dwt_decompose.c ../src/wt.c ../src/wavelets.c ../src/common.c ../src/convolution.c
Wavelet *w = wavelet('d', 2);
MODE mode = MODE_ZEROPAD;
int i;
float input[] = {1,2,3,4,5,6,7,8,9};
float *cA, *cD;
index_t input_len, output_len;
input_len = sizeof input / sizeof input[0];
output_len = dwt_buffer_length(input_len, w->dec_len, mode);
cA = wtcalloc(output_len, sizeof(float));
cD = wtcalloc(output_len, sizeof(float));
printf("Wavelet: %s %d\n\n", w->family_name, w->vanishing_moments_psi);
float_dec_a(input, input_len, w, cA, output_len, mode);
float_dec_d(input, input_len, w, cD, output_len, mode);
for(i=0; i<output_len; i++){
printf("%f ", cA[i]);
}
printf("\n\n");
for(i=0; i<output_len; i++){
printf("%f ", cD[i]);
}
printf("\n");
free_wavelet(w);
wtfree(cA);
wtfree(cD);
return 0;
}
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