libavcodec/qdm2_tablegen.h

   1 /*
   2  * Header file for hardcoded QDM2 tables
   3  *
   4  * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * Libav is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with Libav; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #ifndef AVCODEC_QDM2_TABLEGEN_H
  24 #define AVCODEC_QDM2_TABLEGEN_H
  25
  26 #include <stdint.h>
  27 #include <math.h>
  28 #include "libavutil/attributes.h"
  29
  30 #define SOFTCLIP_THRESHOLD 27600
  31 #define HARDCLIP_THRESHOLD 35716
  32
  33 #if CONFIG_HARDCODED_TABLES
  34 #define softclip_table_init()
  35 #define rnd_table_init()
  36 #define init_noise_samples()
  37 #include "libavcodec/qdm2_tables.h"
  38 #else
  39 static uint16_t softclip_table[HARDCLIP_THRESHOLD - SOFTCLIP_THRESHOLD + 1];
  40 static float noise_table[4096];
  41 static uint8_t random_dequant_index[256][5];
  42 static uint8_t random_dequant_type24[128][3];
  43 static float noise_samples[128];
  44
  45 static av_cold void softclip_table_init(void) {
  46     int i;
  47     double dfl = SOFTCLIP_THRESHOLD - 32767;
  48     float delta = 1.0 / -dfl;
  49     for (i = 0; i < HARDCLIP_THRESHOLD - SOFTCLIP_THRESHOLD + 1; i++)
  50         softclip_table[i] = SOFTCLIP_THRESHOLD - ((int)(sin((float)i * delta) * dfl) & 0x0000FFFF);
  51 }
  52
  53
  54 // random generated table
  55 static av_cold void rnd_table_init(void) {
  56     int i,j;
  57     uint32_t ldw,hdw;
  58     uint64_t tmp64_1;
  59     uint64_t random_seed = 0;
  60     float delta = 1.0 / 16384.0;
  61     for(i = 0; i < 4096 ;i++) {
  62         random_seed = random_seed * 214013 + 2531011;
  63         noise_table[i] = (delta * (float)(((int32_t)random_seed >> 16) & 0x00007FFF)- 1.0) * 1.3;
  64     }
  65
  66     for (i = 0; i < 256 ;i++) {
  67         random_seed = 81;
  68         ldw = i;
  69         for (j = 0; j < 5 ;j++) {
  70             random_dequant_index[i][j] = (uint8_t)((ldw / random_seed) & 0xFF);
  71             ldw = (uint32_t)ldw % (uint32_t)random_seed;
  72             tmp64_1 = (random_seed * 0x55555556);
  73             hdw = (uint32_t)(tmp64_1 >> 32);
  74             random_seed = (uint64_t)(hdw + (ldw >> 31));
  75         }
  76     }
  77     for (i = 0; i < 128 ;i++) {
  78         random_seed = 25;
  79         ldw = i;
  80         for (j = 0; j < 3 ;j++) {
  81             random_dequant_type24[i][j] = (uint8_t)((ldw / random_seed) & 0xFF);
  82             ldw = (uint32_t)ldw % (uint32_t)random_seed;
  83             tmp64_1 = (random_seed * 0x66666667);
  84             hdw = (uint32_t)(tmp64_1 >> 33);
  85             random_seed = hdw + (ldw >> 31);
  86         }
  87     }
  88 }
  89
  90
  91 static av_cold void init_noise_samples(void) {
  92     int i;
  93     unsigned random_seed = 0;
  94     float delta = 1.0 / 16384.0;
  95     for (i = 0; i < 128;i++) {
  96         random_seed = random_seed * 214013 + 2531011;
  97         noise_samples[i] = (delta * (float)((random_seed >> 16) & 0x00007fff) - 1.0);
  98     }
  99 }
 100 #endif /* CONFIG_HARDCODED_TABLES */
 101
 102 #endif /* AVCODEC_QDM2_TABLEGEN_H */