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Diffstat (limited to 'libavcodec/aaccoder_trellis.h')
| -rw-r--r-- | libavcodec/aaccoder_trellis.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/libavcodec/aaccoder_trellis.h b/libavcodec/aaccoder_trellis.h new file mode 100644 index 0000000000..7d685ebe8c --- /dev/null +++ b/libavcodec/aaccoder_trellis.h @@ -0,0 +1,194 @@ +/* + * 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" +#include "aac_tablegen_decl.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; + + abs_pow34_v(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, 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 */ |