void ff_aac_search_for_pred(AACEncContext *s, SingleChannelElement *sce) { int sfb, i, count = 0, cost_coeffs = 0, cost_pred = 0; const int pmax = FFMIN(sce->ics.max_sfb, ff_aac_pred_sfb_max[s->samplerate_index]); float *O34 = &s->scoefs[128*0], *P34 = &s->scoefs[128*1]; float *SENT = &s->scoefs[128*2], *S34 = &s->scoefs[128*3]; float *QERR = &s->scoefs[128*4]; if (sce->ics.window_sequence[0] == EIGHT_SHORT_SEQUENCE) { sce->ics.predictor_present = 0; return; } if (!sce->ics.predictor_initialized) { reset_all_predictors(sce->predictor_state); sce->ics.predictor_initialized = 1; memcpy(sce->prcoeffs, sce->coeffs, 1024*sizeof(float)); for (i = 1; i < 31; i++) sce->ics.predictor_reset_count[i] = i; } update_pred_resets(sce); memcpy(sce->band_alt, sce->band_type, sizeof(sce->band_type)); for (sfb = PRED_SFB_START; sfb < pmax; sfb++) { int cost1, cost2, cb_p; float dist1, dist2, dist_spec_err = 0.0f; const int cb_n = sce->band_type[sfb]; const int start_coef = sce->ics.swb_offset[sfb]; const int num_coeffs = sce->ics.swb_offset[sfb + 1] - start_coef; const FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[sfb]; if (start_coef + num_coeffs > MAX_PREDICTORS || (s->cur_channel && sce->band_type[sfb] >= INTENSITY_BT2) || sce->band_type[sfb] == NOISE_BT) continue; /* Normal coefficients */ abs_pow34_v(O34, &sce->coeffs[start_coef], num_coeffs); dist1 = quantize_and_encode_band_cost(s, NULL, &sce->coeffs[start_coef], NULL, O34, num_coeffs, sce->sf_idx[sfb], cb_n, s->lambda / band->threshold, INFINITY, &cost1, 0); cost_coeffs += cost1; /* Encoded coefficients - needed for #bits, band type and quant. error */ for (i = 0; i < num_coeffs; i++) SENT[i] = sce->coeffs[start_coef + i] - sce->prcoeffs[start_coef + i]; abs_pow34_v(S34, SENT, num_coeffs); if (cb_n < RESERVED_BT) cb_p = find_min_book(find_max_val(1, num_coeffs, S34), sce->sf_idx[sfb]); else cb_p = cb_n; quantize_and_encode_band_cost(s, NULL, SENT, QERR, S34, num_coeffs, sce->sf_idx[sfb], cb_p, s->lambda / band->threshold, INFINITY, &cost2, 0); /* Reconstructed coefficients - needed for distortion measurements */ for (i = 0; i < num_coeffs; i++) sce->prcoeffs[start_coef + i] += QERR[i] != 0.0f ? (sce->prcoeffs[start_coef + i] - QERR[i]) : 0.0f; abs_pow34_v(P34, &sce->prcoeffs[start_coef], num_coeffs); if (cb_n < RESERVED_BT) cb_p = find_min_book(find_max_val(1, num_coeffs, P34), sce->sf_idx[sfb]); else cb_p = cb_n; dist2 = quantize_and_encode_band_cost(s, NULL, &sce->prcoeffs[start_coef], NULL, P34, num_coeffs, sce->sf_idx[sfb], cb_p, s->lambda / band->threshold, INFINITY, NULL, 0); for (i = 0; i < num_coeffs; i++) dist_spec_err += (O34[i] - P34[i])*(O34[i] - P34[i]); dist_spec_err *= s->lambda / band->threshold; dist2 += dist_spec_err; if (dist2 <= dist1 && cb_p <= cb_n) { cost_pred += cost2; sce->ics.prediction_used[sfb] = 1; sce->band_alt[sfb] = cb_n; sce->band_type[sfb] = cb_p; count++; } else { cost_pred += cost1; sce->band_alt[sfb] = cb_p; } } if (count && cost_coeffs < cost_pred) { count = 0; for (sfb = PRED_SFB_START; sfb < pmax; sfb++) RESTORE_PRED(sce, sfb); memset(&sce->ics.prediction_used, 0, sizeof(sce->ics.prediction_used)); } sce->ics.predictor_present = !!count; }