ood-ports-lbsd/graphics/ffmpeg/patches/patch-libavcodec_aaccoder_trellis_h

$OpenBSD: patch-libavcodec_aaccoder_trellis_h,v 1.3 2015/12/06 08:51:46 ajacoutot Exp $

AAC encoder: refactor to resynchronize MIPS port

AAC encoder: Extensive improvements

avcodec/aac_tablegen: get rid of hardcoded tables entirely

--- libavcodec/aaccoder_trellis.h.orig	Sun Nov 29 18:41:41 2015
+++ libavcodec/aaccoder_trellis.h	Sun Nov 29 18:43:26 2015
@@ -0,0 +1,193 @@
+/*
+ * 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;
+
+    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, 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 */