Libav 0.7.1
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00001 /* 00002 * Template for the Discrete Cosine Transform for 32 samples 00003 * Copyright (c) 2001, 2002 Fabrice Bellard 00004 * 00005 * This file is part of Libav. 00006 * 00007 * Libav is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * Libav is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with Libav; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 #include "dct32.h" 00023 #include "mathops.h" 00024 00025 #if DCT32_FLOAT 00026 # define dct32 ff_dct32_float 00027 # define FIXHR(x) ((float)(x)) 00028 # define MULH3(x, y, s) ((s)*(y)*(x)) 00029 # define INTFLOAT float 00030 #else 00031 # define dct32 ff_dct32_fixed 00032 # define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5)) 00033 # define MULH3(x, y, s) MULH((s)*(x), y) 00034 # define INTFLOAT int 00035 #endif 00036 00037 00038 /* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */ 00039 00040 /* cos(i*pi/64) */ 00041 00042 #define COS0_0 FIXHR(0.50060299823519630134/2) 00043 #define COS0_1 FIXHR(0.50547095989754365998/2) 00044 #define COS0_2 FIXHR(0.51544730992262454697/2) 00045 #define COS0_3 FIXHR(0.53104259108978417447/2) 00046 #define COS0_4 FIXHR(0.55310389603444452782/2) 00047 #define COS0_5 FIXHR(0.58293496820613387367/2) 00048 #define COS0_6 FIXHR(0.62250412303566481615/2) 00049 #define COS0_7 FIXHR(0.67480834145500574602/2) 00050 #define COS0_8 FIXHR(0.74453627100229844977/2) 00051 #define COS0_9 FIXHR(0.83934964541552703873/2) 00052 #define COS0_10 FIXHR(0.97256823786196069369/2) 00053 #define COS0_11 FIXHR(1.16943993343288495515/4) 00054 #define COS0_12 FIXHR(1.48416461631416627724/4) 00055 #define COS0_13 FIXHR(2.05778100995341155085/8) 00056 #define COS0_14 FIXHR(3.40760841846871878570/8) 00057 #define COS0_15 FIXHR(10.19000812354805681150/32) 00058 00059 #define COS1_0 FIXHR(0.50241928618815570551/2) 00060 #define COS1_1 FIXHR(0.52249861493968888062/2) 00061 #define COS1_2 FIXHR(0.56694403481635770368/2) 00062 #define COS1_3 FIXHR(0.64682178335999012954/2) 00063 #define COS1_4 FIXHR(0.78815462345125022473/2) 00064 #define COS1_5 FIXHR(1.06067768599034747134/4) 00065 #define COS1_6 FIXHR(1.72244709823833392782/4) 00066 #define COS1_7 FIXHR(5.10114861868916385802/16) 00067 00068 #define COS2_0 FIXHR(0.50979557910415916894/2) 00069 #define COS2_1 FIXHR(0.60134488693504528054/2) 00070 #define COS2_2 FIXHR(0.89997622313641570463/2) 00071 #define COS2_3 FIXHR(2.56291544774150617881/8) 00072 00073 #define COS3_0 FIXHR(0.54119610014619698439/2) 00074 #define COS3_1 FIXHR(1.30656296487637652785/4) 00075 00076 #define COS4_0 FIXHR(0.70710678118654752439/2) 00077 00078 /* butterfly operator */ 00079 #define BF(a, b, c, s)\ 00080 {\ 00081 tmp0 = val##a + val##b;\ 00082 tmp1 = val##a - val##b;\ 00083 val##a = tmp0;\ 00084 val##b = MULH3(tmp1, c, 1<<(s));\ 00085 } 00086 00087 #define BF0(a, b, c, s)\ 00088 {\ 00089 tmp0 = tab[a] + tab[b];\ 00090 tmp1 = tab[a] - tab[b];\ 00091 val##a = tmp0;\ 00092 val##b = MULH3(tmp1, c, 1<<(s));\ 00093 } 00094 00095 #define BF1(a, b, c, d)\ 00096 {\ 00097 BF(a, b, COS4_0, 1);\ 00098 BF(c, d,-COS4_0, 1);\ 00099 val##c += val##d;\ 00100 } 00101 00102 #define BF2(a, b, c, d)\ 00103 {\ 00104 BF(a, b, COS4_0, 1);\ 00105 BF(c, d,-COS4_0, 1);\ 00106 val##c += val##d;\ 00107 val##a += val##c;\ 00108 val##c += val##b;\ 00109 val##b += val##d;\ 00110 } 00111 00112 #define ADD(a, b) val##a += val##b 00113 00114 /* DCT32 without 1/sqrt(2) coef zero scaling. */ 00115 void dct32(INTFLOAT *out, const INTFLOAT *tab) 00116 { 00117 INTFLOAT tmp0, tmp1; 00118 00119 INTFLOAT val0 , val1 , val2 , val3 , val4 , val5 , val6 , val7 , 00120 val8 , val9 , val10, val11, val12, val13, val14, val15, 00121 val16, val17, val18, val19, val20, val21, val22, val23, 00122 val24, val25, val26, val27, val28, val29, val30, val31; 00123 00124 /* pass 1 */ 00125 BF0( 0, 31, COS0_0 , 1); 00126 BF0(15, 16, COS0_15, 5); 00127 /* pass 2 */ 00128 BF( 0, 15, COS1_0 , 1); 00129 BF(16, 31,-COS1_0 , 1); 00130 /* pass 1 */ 00131 BF0( 7, 24, COS0_7 , 1); 00132 BF0( 8, 23, COS0_8 , 1); 00133 /* pass 2 */ 00134 BF( 7, 8, COS1_7 , 4); 00135 BF(23, 24,-COS1_7 , 4); 00136 /* pass 3 */ 00137 BF( 0, 7, COS2_0 , 1); 00138 BF( 8, 15,-COS2_0 , 1); 00139 BF(16, 23, COS2_0 , 1); 00140 BF(24, 31,-COS2_0 , 1); 00141 /* pass 1 */ 00142 BF0( 3, 28, COS0_3 , 1); 00143 BF0(12, 19, COS0_12, 2); 00144 /* pass 2 */ 00145 BF( 3, 12, COS1_3 , 1); 00146 BF(19, 28,-COS1_3 , 1); 00147 /* pass 1 */ 00148 BF0( 4, 27, COS0_4 , 1); 00149 BF0(11, 20, COS0_11, 2); 00150 /* pass 2 */ 00151 BF( 4, 11, COS1_4 , 1); 00152 BF(20, 27,-COS1_4 , 1); 00153 /* pass 3 */ 00154 BF( 3, 4, COS2_3 , 3); 00155 BF(11, 12,-COS2_3 , 3); 00156 BF(19, 20, COS2_3 , 3); 00157 BF(27, 28,-COS2_3 , 3); 00158 /* pass 4 */ 00159 BF( 0, 3, COS3_0 , 1); 00160 BF( 4, 7,-COS3_0 , 1); 00161 BF( 8, 11, COS3_0 , 1); 00162 BF(12, 15,-COS3_0 , 1); 00163 BF(16, 19, COS3_0 , 1); 00164 BF(20, 23,-COS3_0 , 1); 00165 BF(24, 27, COS3_0 , 1); 00166 BF(28, 31,-COS3_0 , 1); 00167 00168 00169 00170 /* pass 1 */ 00171 BF0( 1, 30, COS0_1 , 1); 00172 BF0(14, 17, COS0_14, 3); 00173 /* pass 2 */ 00174 BF( 1, 14, COS1_1 , 1); 00175 BF(17, 30,-COS1_1 , 1); 00176 /* pass 1 */ 00177 BF0( 6, 25, COS0_6 , 1); 00178 BF0( 9, 22, COS0_9 , 1); 00179 /* pass 2 */ 00180 BF( 6, 9, COS1_6 , 2); 00181 BF(22, 25,-COS1_6 , 2); 00182 /* pass 3 */ 00183 BF( 1, 6, COS2_1 , 1); 00184 BF( 9, 14,-COS2_1 , 1); 00185 BF(17, 22, COS2_1 , 1); 00186 BF(25, 30,-COS2_1 , 1); 00187 00188 /* pass 1 */ 00189 BF0( 2, 29, COS0_2 , 1); 00190 BF0(13, 18, COS0_13, 3); 00191 /* pass 2 */ 00192 BF( 2, 13, COS1_2 , 1); 00193 BF(18, 29,-COS1_2 , 1); 00194 /* pass 1 */ 00195 BF0( 5, 26, COS0_5 , 1); 00196 BF0(10, 21, COS0_10, 1); 00197 /* pass 2 */ 00198 BF( 5, 10, COS1_5 , 2); 00199 BF(21, 26,-COS1_5 , 2); 00200 /* pass 3 */ 00201 BF( 2, 5, COS2_2 , 1); 00202 BF(10, 13,-COS2_2 , 1); 00203 BF(18, 21, COS2_2 , 1); 00204 BF(26, 29,-COS2_2 , 1); 00205 /* pass 4 */ 00206 BF( 1, 2, COS3_1 , 2); 00207 BF( 5, 6,-COS3_1 , 2); 00208 BF( 9, 10, COS3_1 , 2); 00209 BF(13, 14,-COS3_1 , 2); 00210 BF(17, 18, COS3_1 , 2); 00211 BF(21, 22,-COS3_1 , 2); 00212 BF(25, 26, COS3_1 , 2); 00213 BF(29, 30,-COS3_1 , 2); 00214 00215 /* pass 5 */ 00216 BF1( 0, 1, 2, 3); 00217 BF2( 4, 5, 6, 7); 00218 BF1( 8, 9, 10, 11); 00219 BF2(12, 13, 14, 15); 00220 BF1(16, 17, 18, 19); 00221 BF2(20, 21, 22, 23); 00222 BF1(24, 25, 26, 27); 00223 BF2(28, 29, 30, 31); 00224 00225 /* pass 6 */ 00226 00227 ADD( 8, 12); 00228 ADD(12, 10); 00229 ADD(10, 14); 00230 ADD(14, 9); 00231 ADD( 9, 13); 00232 ADD(13, 11); 00233 ADD(11, 15); 00234 00235 out[ 0] = val0; 00236 out[16] = val1; 00237 out[ 8] = val2; 00238 out[24] = val3; 00239 out[ 4] = val4; 00240 out[20] = val5; 00241 out[12] = val6; 00242 out[28] = val7; 00243 out[ 2] = val8; 00244 out[18] = val9; 00245 out[10] = val10; 00246 out[26] = val11; 00247 out[ 6] = val12; 00248 out[22] = val13; 00249 out[14] = val14; 00250 out[30] = val15; 00251 00252 ADD(24, 28); 00253 ADD(28, 26); 00254 ADD(26, 30); 00255 ADD(30, 25); 00256 ADD(25, 29); 00257 ADD(29, 27); 00258 ADD(27, 31); 00259 00260 out[ 1] = val16 + val24; 00261 out[17] = val17 + val25; 00262 out[ 9] = val18 + val26; 00263 out[25] = val19 + val27; 00264 out[ 5] = val20 + val28; 00265 out[21] = val21 + val29; 00266 out[13] = val22 + val30; 00267 out[29] = val23 + val31; 00268 out[ 3] = val24 + val20; 00269 out[19] = val25 + val21; 00270 out[11] = val26 + val22; 00271 out[27] = val27 + val23; 00272 out[ 7] = val28 + val18; 00273 out[23] = val29 + val19; 00274 out[15] = val30 + val17; 00275 out[31] = val31; 00276 }