Problem in using SpeexPreprocess

Hi,

I wrote to a program looking at the api reference to pre-process noisy
speech using SpeexPreprocess api. Code listing is the following:
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#include <stdio.h>
#include <speex/speex_preprocess.h>

#define FRAME_SIZE 160
#define SAMPLING_RATE 8000

int main(int argc, char **argv)
{
    SpeexPreprocessState *preprocess_state =
speex_preprocess_state_init(FRAME_SIZE, SAMPLING_RATE);

    FILE *fin = fopen(argv[1], "r");
    FILE *fout = fopen(argv[2], "wb");

    short in[FRAME_SIZE]; //float input[FRAME_SIZE];
    char cbits[200];
    int nbBytes;

    while (1)
    {
        fread(in, sizeof(short), FRAME_SIZE, fin);
        if (feof(fin)) break;

        speex_preprocess_estimate_update(preprocess_state, in);
        speex_preprocess_run(preprocess_state, in);

        fwrite(in, sizeof(short), FRAME_SIZE, fout);
   }
   speex_preprocess_state_destroy(preprocess_state);
   fclose(fin);  fclose(fout);
   return 0;
}
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The inputs to the program are input.wav and output.wav.


But the program doesnt filter any noise. Please correct if I made any
mistake in the program.

Thank you,
- Anil