quicktime/ffmpeg/libavcodec/faandct.c

   1 /*
   2  * Floating point AAN DCT
   3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  * this implementation is based upon the IJG integer AAN DCT (see jfdctfst.c)
  20  */
  21
  22 /**
  23  * @file faandct.c
  24  * @brief
  25  *     Floating point AAN DCT
  26  * @author Michael Niedermayer <michaelni@gmx.at>
  27  */
  28
  29 #include "dsputil.h"
  30 #include "faandct.h"
  31
  32 #define FLOAT float
  33 #ifdef FAAN_POSTSCALE
  34 #    define SCALE(x) postscale[x]
  35 #else
  36 #    define SCALE(x) 1
  37 #endif
  38
  39 //numbers generated by simple c code (not as accurate as they could be)
  40 /*
  41 for(i=0; i<8; i++){
  42     printf("#define B%d %1.20llf\n", i, (long double)1.0/(cosl(i*acosl(-1.0)/(long double)16.0)*sqrtl(2)));
  43 }
  44 */
  45 #define B0 1.00000000000000000000
  46 #define B1 0.72095982200694791383 // (cos(pi*1/16)sqrt(2))^-1
  47 #define B2 0.76536686473017954350 // (cos(pi*2/16)sqrt(2))^-1
  48 #define B3 0.85043009476725644878 // (cos(pi*3/16)sqrt(2))^-1
  49 #define B4 1.00000000000000000000 // (cos(pi*4/16)sqrt(2))^-1
  50 #define B5 1.27275858057283393842 // (cos(pi*5/16)sqrt(2))^-1
  51 #define B6 1.84775906502257351242 // (cos(pi*6/16)sqrt(2))^-1
  52 #define B7 3.62450978541155137218 // (cos(pi*7/16)sqrt(2))^-1
  53
  54
  55 #define A1 0.70710678118654752438 // cos(pi*4/16)
  56 #define A2 0.54119610014619698435 // cos(pi*6/16)sqrt(2)
  57 #define A5 0.38268343236508977170 // cos(pi*6/16)
  58 #define A4 1.30656296487637652774 // cos(pi*2/16)sqrt(2)
  59
  60 static FLOAT postscale[64]={
  61 B0*B0, B0*B1, B0*B2, B0*B3, B0*B4, B0*B5, B0*B6, B0*B7,
  62 B1*B0, B1*B1, B1*B2, B1*B3, B1*B4, B1*B5, B1*B6, B1*B7,
  63 B2*B0, B2*B1, B2*B2, B2*B3, B2*B4, B2*B5, B2*B6, B2*B7,
  64 B3*B0, B3*B1, B3*B2, B3*B3, B3*B4, B3*B5, B3*B6, B3*B7,
  65 B4*B0, B4*B1, B4*B2, B4*B3, B4*B4, B4*B5, B4*B6, B4*B7,
  66 B5*B0, B5*B1, B5*B2, B5*B3, B5*B4, B5*B5, B5*B6, B5*B7,
  67 B6*B0, B6*B1, B6*B2, B6*B3, B6*B4, B6*B5, B6*B6, B6*B7,
  68 B7*B0, B7*B1, B7*B2, B7*B3, B7*B4, B7*B5, B7*B6, B7*B7,
  69 };
  70
  71 static always_inline void row_fdct(FLOAT temp[64], DCTELEM * data)
  72 {
  73     FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
  74     FLOAT tmp10, tmp11, tmp12, tmp13;
  75     FLOAT z1, z2, z3, z4, z5, z11, z13;
  76     int i;
  77
  78     for (i=0; i<8*8; i+=8) {
  79         tmp0= data[0 + i] + data[7 + i];
  80         tmp7= data[0 + i] - data[7 + i];
  81         tmp1= data[1 + i] + data[6 + i];
  82         tmp6= data[1 + i] - data[6 + i];
  83         tmp2= data[2 + i] + data[5 + i];
  84         tmp5= data[2 + i] - data[5 + i];
  85         tmp3= data[3 + i] + data[4 + i];
  86         tmp4= data[3 + i] - data[4 + i];
  87
  88         tmp10= tmp0 + tmp3;
  89         tmp13= tmp0 - tmp3;
  90         tmp11= tmp1 + tmp2;
  91         tmp12= tmp1 - tmp2;
  92
  93         temp[0 + i]= tmp10 + tmp11;
  94         temp[4 + i]= tmp10 - tmp11;
  95
  96         z1= (tmp12 + tmp13)*A1;
  97         temp[2 + i]= tmp13 + z1;
  98         temp[6 + i]= tmp13 - z1;
  99
 100         tmp10= tmp4 + tmp5;
 101         tmp11= tmp5 + tmp6;
 102         tmp12= tmp6 + tmp7;
 103
 104         z5= (tmp10 - tmp12) * A5;
 105         z2= tmp10*A2 + z5;
 106         z4= tmp12*A4 + z5;
 107         z3= tmp11*A1;
 108
 109         z11= tmp7 + z3;
 110         z13= tmp7 - z3;
 111
 112         temp[5 + i]= z13 + z2;
 113         temp[3 + i]= z13 - z2;
 114         temp[1 + i]= z11 + z4;
 115         temp[7 + i]= z11 - z4;
 116     }
 117 }
 118
 119 void ff_faandct(DCTELEM * data)
 120 {
 121     FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
 122     FLOAT tmp10, tmp11, tmp12, tmp13;
 123     FLOAT z1, z2, z3, z4, z5, z11, z13;
 124     FLOAT temp[64];
 125     int i;
 126
 127     emms_c();
 128
 129     row_fdct(temp, data);
 130
 131     for (i=0; i<8; i++) {
 132         tmp0= temp[8*0 + i] + temp[8*7 + i];
 133         tmp7= temp[8*0 + i] - temp[8*7 + i];
 134         tmp1= temp[8*1 + i] + temp[8*6 + i];
 135         tmp6= temp[8*1 + i] - temp[8*6 + i];
 136         tmp2= temp[8*2 + i] + temp[8*5 + i];
 137         tmp5= temp[8*2 + i] - temp[8*5 + i];
 138         tmp3= temp[8*3 + i] + temp[8*4 + i];
 139         tmp4= temp[8*3 + i] - temp[8*4 + i];
 140
 141         tmp10= tmp0 + tmp3;
 142         tmp13= tmp0 - tmp3;
 143         tmp11= tmp1 + tmp2;
 144         tmp12= tmp1 - tmp2;
 145
 146         data[8*0 + i]= lrintf(SCALE(8*0 + i) * (tmp10 + tmp11));
 147         data[8*4 + i]= lrintf(SCALE(8*4 + i) * (tmp10 - tmp11));
 148
 149         z1= (tmp12 + tmp13)* A1;
 150         data[8*2 + i]= lrintf(SCALE(8*2 + i) * (tmp13 + z1));
 151         data[8*6 + i]= lrintf(SCALE(8*6 + i) * (tmp13 - z1));
 152
 153         tmp10= tmp4 + tmp5;
 154         tmp11= tmp5 + tmp6;
 155         tmp12= tmp6 + tmp7;
 156
 157         z5= (tmp10 - tmp12) * A5;
 158         z2= tmp10*A2 + z5;
 159         z4= tmp12*A4 + z5;
 160         z3= tmp11*A1;
 161
 162         z11= tmp7 + z3;
 163         z13= tmp7 - z3;
 164
 165         data[8*5 + i]= lrintf(SCALE(8*5 + i) * (z13 + z2));
 166         data[8*3 + i]= lrintf(SCALE(8*3 + i) * (z13 - z2));
 167         data[8*1 + i]= lrintf(SCALE(8*1 + i) * (z11 + z4));
 168         data[8*7 + i]= lrintf(SCALE(8*7 + i) * (z11 - z4));
 169     }
 170 }
 171
 172 void ff_faandct248(DCTELEM * data)
 173 {
 174     FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
 175     FLOAT tmp10, tmp11, tmp12, tmp13;
 176     FLOAT z1;
 177     FLOAT temp[64];
 178     int i;
 179
 180     emms_c();
 181
 182     row_fdct(temp, data);
 183
 184     for (i=0; i<8; i++) {
 185         tmp0 = temp[8*0 + i] + temp[8*1 + i];
 186         tmp1 = temp[8*2 + i] + temp[8*3 + i];
 187         tmp2 = temp[8*4 + i] + temp[8*5 + i];
 188         tmp3 = temp[8*6 + i] + temp[8*7 + i];
 189         tmp4 = temp[8*0 + i] - temp[8*1 + i];
 190         tmp5 = temp[8*2 + i] - temp[8*3 + i];
 191         tmp6 = temp[8*4 + i] - temp[8*5 + i];
 192         tmp7 = temp[8*6 + i] - temp[8*7 + i];
 193
 194         tmp10 = tmp0 + tmp3;
 195         tmp11 = tmp1 + tmp2;
 196         tmp12 = tmp1 - tmp2;
 197         tmp13 = tmp0 - tmp3;
 198
 199         data[8*0 + i] = lrintf(SCALE(8*0 + i) * (tmp10 + tmp11));
 200         data[8*4 + i] = lrintf(SCALE(8*4 + i) * (tmp10 - tmp11));
 201
 202         z1 = (tmp12 + tmp13)* A1;
 203         data[8*2 + i] = lrintf(SCALE(8*2 + i) * (tmp13 + z1));
 204         data[8*6 + i] = lrintf(SCALE(8*6 + i) * (tmp13 - z1));
 205
 206         tmp10 = tmp4 + tmp7;
 207         tmp11 = tmp5 + tmp6;
 208         tmp12 = tmp5 - tmp6;
 209         tmp13 = tmp4 - tmp7;
 210
 211         data[8*1 + i] = lrintf(SCALE(8*0 + i) * (tmp10 + tmp11));
 212         data[8*5 + i] = lrintf(SCALE(8*4 + i) * (tmp10 - tmp11));
 213
 214         z1 = (tmp12 + tmp13)* A1;
 215         data[8*3 + i] = lrintf(SCALE(8*2 + i) * (tmp13 + z1));
 216         data[8*7 + i] = lrintf(SCALE(8*6 + i) * (tmp13 - z1));
 217     }
 218 }