static int64_t find_best_filter(const DCAADPCMEncContext *s, const int32_t *in, int len) { const premultiplied_coeffs *precalc_data = s->private_data; int i, j, k = 0; int vq; int64_t err; int64_t min_err = 1ll << 62; int64_t corr[15]; for (i = 0; i <= DCA_ADPCM_COEFFS; i++) for (j = i; j <= DCA_ADPCM_COEFFS; j++) corr[k++] = calc_corr(in+4, len, i, j); for (i = 0; i < DCA_ADPCM_VQCODEBOOK_SZ; i++) { err = apply_filter(ff_dca_adpcm_vb[i], corr, *precalc_data); if (err < min_err) { min_err = err; vq = i; } precalc_data++; } return vq; }