static void codebook_trellis_rate(AACEncContext *s, SingleChannelElement *sce, int win, int group_len, const float lambda) { BandCodingPath path[120][12]; int w, swb, cb, start, size; int i, j; const int max_sfb = sce->ics.max_sfb; const int run_bits = sce->ics.num_windows == 1 ? 5 : 3; const int run_esc = (1 << run_bits) - 1; int idx, ppos, count; int stackrun[120], stackcb[120], stack_len; float next_minbits = INFINITY; int next_mincb = 0; abs_pow34_v(s->scoefs, sce->coeffs, 1024); start = win*128; for (cb = 0; cb < 12; cb++) { path[0][cb].cost = run_bits+4; path[0][cb].prev_idx = -1; path[0][cb].run = 0; } for (swb = 0; swb < max_sfb; swb++) { size = sce->ics.swb_sizes[swb]; if (sce->zeroes[win*16 + swb]) { float cost_stay_here = path[swb][0].cost; float cost_get_here = next_minbits + run_bits + 4; if ( run_value_bits[sce->ics.num_windows == 8][path[swb][0].run] != run_value_bits[sce->ics.num_windows == 8][path[swb][0].run+1]) cost_stay_here += run_bits; if (cost_get_here < cost_stay_here) { path[swb+1][0].prev_idx = next_mincb; path[swb+1][0].cost = cost_get_here; path[swb+1][0].run = 1; } else { path[swb+1][0].prev_idx = 0; path[swb+1][0].cost = cost_stay_here; path[swb+1][0].run = path[swb][0].run + 1; } next_minbits = path[swb+1][0].cost; next_mincb = 0; for (cb = 1; cb < 12; cb++) { path[swb+1][cb].cost = 61450; path[swb+1][cb].prev_idx = -1; path[swb+1][cb].run = 0; } } else { float minbits = next_minbits; int mincb = next_mincb; int startcb = sce->band_type[win*16+swb]; next_minbits = INFINITY; next_mincb = 0; for (cb = 0; cb < startcb; cb++) { path[swb+1][cb].cost = 61450; path[swb+1][cb].prev_idx = -1; path[swb+1][cb].run = 0; } for (cb = startcb; cb < 12; cb++) { float cost_stay_here, cost_get_here; float bits = 0.0f; for (w = 0; w < group_len; w++) { bits += quantize_band_cost(s, sce->coeffs + start + w*128, s->scoefs + start + w*128, size, sce->sf_idx[(win+w)*16+swb], cb, 0, INFINITY, NULL); } cost_stay_here = path[swb][cb].cost + bits; cost_get_here = minbits + bits + run_bits + 4; if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run] != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1]) cost_stay_here += run_bits; if (cost_get_here < cost_stay_here) { path[swb+1][cb].prev_idx = mincb; path[swb+1][cb].cost = cost_get_here; path[swb+1][cb].run = 1; } else { path[swb+1][cb].prev_idx = cb; path[swb+1][cb].cost = cost_stay_here; path[swb+1][cb].run = path[swb][cb].run + 1; } if (path[swb+1][cb].cost < next_minbits) { next_minbits = path[swb+1][cb].cost; next_mincb = cb; } } } start += sce->ics.swb_sizes[swb]; } //convert resulting path from backward-linked list stack_len = 0; idx = 0; for (cb = 1; cb < 12; cb++) if (path[max_sfb][cb].cost < path[max_sfb][idx].cost) idx = cb; ppos = max_sfb; while (ppos > 0) { av_assert1(idx >= 0); cb = idx; stackrun[stack_len] = path[ppos][cb].run; stackcb [stack_len] = cb; idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx; ppos -= path[ppos][cb].run; stack_len++; } //perform actual band info encoding start = 0; for (i = stack_len - 1; i >= 0; i--) { put_bits(&s->pb, 4, stackcb[i]); count = stackrun[i]; memset(sce->zeroes + win*16 + start, !stackcb[i], count); //XXX: memset when band_type is also uint8_t for (j = 0; j < count; j++) { sce->band_type[win*16 + start] = stackcb[i]; start++; } while (count >= run_esc) { put_bits(&s->pb, run_bits, run_esc); count -= run_esc; } put_bits(&s->pb, run_bits, count); } }