double log_truncated_nb_frames = floor(log2(2*nb_frames));
    int truncated_nb_frames = (int)ceil(pow(2,log_truncated_nb_frames));

    band_sum = calloc(truncated_nb_frames, sizeof(FFTSample));
    for(int j = 0; j < truncated_nb_frames - 1; ++j) {
        for(int i = 0; i < 36; ++i) {
            band_sum[j] += weighted_average[i][j];
        }
    }

    fft = av_rdft_init((int)log_truncated_nb_frames, DFT_R2C);
    final_fft = calloc(truncated_nb_frames, sizeof(FFTSample));

    av_rdft_calc(fft, band_sum);