| /* |
| * AAC encoder trellis codebook selector |
| * Copyright (C) 2008-2009 Konstantin Shishkov |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * AAC encoder trellis codebook selector |
| * @author Konstantin Shishkov |
| */ |
| |
| /** |
| * This file contains a template for the codebook_trellis_rate selector function. |
| * It needs to be provided, externally, as an already included declaration, |
| * the following functions from aacenc_quantization/util.h. They're not included |
| * explicitly here to make it possible to provide alternative implementations: |
| * - quantize_band_cost_bits |
| * - abs_pow34_v |
| */ |
| |
| #ifndef AVCODEC_AACCODER_TRELLIS_H |
| #define AVCODEC_AACCODER_TRELLIS_H |
| |
| #include <float.h> |
| #include "libavutil/mathematics.h" |
| #include "avcodec.h" |
| #include "put_bits.h" |
| #include "aac.h" |
| #include "aacenc.h" |
| #include "aactab.h" |
| #include "aacenctab.h" |
| |
| /** |
| * structure used in optimal codebook search |
| */ |
| typedef struct TrellisBandCodingPath { |
| int prev_idx; ///< pointer to the previous path point |
| float cost; ///< path cost |
| int run; |
| } TrellisBandCodingPath; |
| |
| |
| static void codebook_trellis_rate(AACEncContext *s, SingleChannelElement *sce, |
| int win, int group_len, const float lambda) |
| { |
| TrellisBandCodingPath path[120][CB_TOT_ALL]; |
| 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; |
| |
| s->abs_pow34(s->scoefs, sce->coeffs, 1024); |
| start = win*128; |
| for (cb = 0; cb < CB_TOT_ALL; 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 < CB_TOT_ALL; 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]; |
| startcb = aac_cb_in_map[startcb]; |
| 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 < CB_TOT_ALL; cb++) { |
| float cost_stay_here, cost_get_here; |
| float bits = 0.0f; |
| if (cb >= 12 && sce->band_type[win*16+swb] != aac_cb_out_map[cb]) { |
| path[swb+1][cb].cost = 61450; |
| path[swb+1][cb].prev_idx = -1; |
| path[swb+1][cb].run = 0; |
| continue; |
| } |
| for (w = 0; w < group_len; w++) { |
| bits += quantize_band_cost_bits(s, &sce->coeffs[start + w*128], |
| &s->scoefs[start + w*128], size, |
| sce->sf_idx[win*16+swb], |
| aac_cb_out_map[cb], |
| 0, INFINITY, NULL, NULL, 0); |
| } |
| 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 < CB_TOT_ALL; 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--) { |
| cb = aac_cb_out_map[stackcb[i]]; |
| put_bits(&s->pb, 4, cb); |
| count = stackrun[i]; |
| memset(sce->zeroes + win*16 + start, !cb, count); |
| //XXX: memset when band_type is also uint8_t |
| for (j = 0; j < count; j++) { |
| sce->band_type[win*16 + start] = cb; |
| start++; |
| } |
| while (count >= run_esc) { |
| put_bits(&s->pb, run_bits, run_esc); |
| count -= run_esc; |
| } |
| put_bits(&s->pb, run_bits, count); |
| } |
| } |
| |
| |
| #endif /* AVCODEC_AACCODER_TRELLIS_H */ |
