/* * Template for the Discrete Cosine Transform for 32 samples * Copyright (c) 2001, 2002 Fabrice Bellard * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "dct32.h" #include "mathops.h" #if DCT32_FLOAT # define dct32 ff_dct32_float # define FIXHR(x) ((float)(x)) # define MULH3(x, y, s) ((s)*(y)*(x)) # define INTFLOAT float #else # define dct32 ff_dct32_fixed # define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5)) # define MULH3(x, y, s) MULH((s)*(x), y) # define INTFLOAT int #endif /* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */ /* cos(i*pi/64) */ #define COS0_0 FIXHR(0.50060299823519630134/2) #define COS0_1 FIXHR(0.50547095989754365998/2) #define COS0_2 FIXHR(0.51544730992262454697/2) #define COS0_3 FIXHR(0.53104259108978417447/2) #define COS0_4 FIXHR(0.55310389603444452782/2) #define COS0_5 FIXHR(0.58293496820613387367/2) #define COS0_6 FIXHR(0.62250412303566481615/2) #define COS0_7 FIXHR(0.67480834145500574602/2) #define COS0_8 FIXHR(0.74453627100229844977/2) #define COS0_9 FIXHR(0.83934964541552703873/2) #define COS0_10 FIXHR(0.97256823786196069369/2) #define COS0_11 FIXHR(1.16943993343288495515/4) #define COS0_12 FIXHR(1.48416461631416627724/4) #define COS0_13 FIXHR(2.05778100995341155085/8) #define COS0_14 FIXHR(3.40760841846871878570/8) #define COS0_15 FIXHR(10.19000812354805681150/32) #define COS1_0 FIXHR(0.50241928618815570551/2) #define COS1_1 FIXHR(0.52249861493968888062/2) #define COS1_2 FIXHR(0.56694403481635770368/2) #define COS1_3 FIXHR(0.64682178335999012954/2) #define COS1_4 FIXHR(0.78815462345125022473/2) #define COS1_5 FIXHR(1.06067768599034747134/4) #define COS1_6 FIXHR(1.72244709823833392782/4) #define COS1_7 FIXHR(5.10114861868916385802/16) #define COS2_0 FIXHR(0.50979557910415916894/2) #define COS2_1 FIXHR(0.60134488693504528054/2) #define COS2_2 FIXHR(0.89997622313641570463/2) #define COS2_3 FIXHR(2.56291544774150617881/8) #define COS3_0 FIXHR(0.54119610014619698439/2) #define COS3_1 FIXHR(1.30656296487637652785/4) #define COS4_0 FIXHR(0.70710678118654752439/2) /* butterfly operator */ #define BF(a, b, c, s)\ {\ tmp0 = val##a + val##b;\ tmp1 = val##a - val##b;\ val##a = tmp0;\ val##b = MULH3(tmp1, c, 1<<(s));\ } #define BF0(a, b, c, s)\ {\ tmp0 = tab[a] + tab[b];\ tmp1 = tab[a] - tab[b];\ val##a = tmp0;\ val##b = MULH3(tmp1, c, 1<<(s));\ } #define BF1(a, b, c, d)\ {\ BF(a, b, COS4_0, 1);\ BF(c, d,-COS4_0, 1);\ val##c += val##d;\ } #define BF2(a, b, c, d)\ {\ BF(a, b, COS4_0, 1);\ BF(c, d,-COS4_0, 1);\ val##c += val##d;\ val##a += val##c;\ val##c += val##b;\ val##b += val##d;\ } #define ADD(a, b) val##a += val##b /* DCT32 without 1/sqrt(2) coef zero scaling. */ void dct32(INTFLOAT *out, const INTFLOAT *tab) { INTFLOAT tmp0, tmp1; INTFLOAT val0 , val1 , val2 , val3 , val4 , val5 , val6 , val7 , val8 , val9 , val10, val11, val12, val13, val14, val15, val16, val17, val18, val19, val20, val21, val22, val23, val24, val25, val26, val27, val28, val29, val30, val31; /* pass 1 */ BF0( 0, 31, COS0_0 , 1); BF0(15, 16, COS0_15, 5); /* pass 2 */ BF( 0, 15, COS1_0 , 1); BF(16, 31,-COS1_0 , 1); /* pass 1 */ BF0( 7, 24, COS0_7 , 1); BF0( 8, 23, COS0_8 , 1); /* pass 2 */ BF( 7, 8, COS1_7 , 4); BF(23, 24,-COS1_7 , 4); /* pass 3 */ BF( 0, 7, COS2_0 , 1); BF( 8, 15,-COS2_0 , 1); BF(16, 23, COS2_0 , 1); BF(24, 31,-COS2_0 , 1); /* pass 1 */ BF0( 3, 28, COS0_3 , 1); BF0(12, 19, COS0_12, 2); /* pass 2 */ BF( 3, 12, COS1_3 , 1); BF(19, 28,-COS1_3 , 1); /* pass 1 */ BF0( 4, 27, COS0_4 , 1); BF0(11, 20, COS0_11, 2); /* pass 2 */ BF( 4, 11, COS1_4 , 1); BF(20, 27,-COS1_4 , 1); /* pass 3 */ BF( 3, 4, COS2_3 , 3); BF(11, 12,-COS2_3 , 3); BF(19, 20, COS2_3 , 3); BF(27, 28,-COS2_3 , 3); /* pass 4 */ BF( 0, 3, COS3_0 , 1); BF( 4, 7,-COS3_0 , 1); BF( 8, 11, COS3_0 , 1); BF(12, 15,-COS3_0 , 1); BF(16, 19, COS3_0 , 1); BF(20, 23,-COS3_0 , 1); BF(24, 27, COS3_0 , 1); BF(28, 31,-COS3_0 , 1); /* pass 1 */ BF0( 1, 30, COS0_1 , 1); BF0(14, 17, COS0_14, 3); /* pass 2 */ BF( 1, 14, COS1_1 , 1); BF(17, 30,-COS1_1 , 1); /* pass 1 */ BF0( 6, 25, COS0_6 , 1); BF0( 9, 22, COS0_9 , 1); /* pass 2 */ BF( 6, 9, COS1_6 , 2); BF(22, 25,-COS1_6 , 2); /* pass 3 */ BF( 1, 6, COS2_1 , 1); BF( 9, 14,-COS2_1 , 1); BF(17, 22, COS2_1 , 1); BF(25, 30,-COS2_1 , 1); /* pass 1 */ BF0( 2, 29, COS0_2 , 1); BF0(13, 18, COS0_13, 3); /* pass 2 */ BF( 2, 13, COS1_2 , 1); BF(18, 29,-COS1_2 , 1); /* pass 1 */ BF0( 5, 26, COS0_5 , 1); BF0(10, 21, COS0_10, 1); /* pass 2 */ BF( 5, 10, COS1_5 , 2); BF(21, 26,-COS1_5 , 2); /* pass 3 */ BF( 2, 5, COS2_2 , 1); BF(10, 13,-COS2_2 , 1); BF(18, 21, COS2_2 , 1); BF(26, 29,-COS2_2 , 1); /* pass 4 */ BF( 1, 2, COS3_1 , 2); BF( 5, 6,-COS3_1 , 2); BF( 9, 10, COS3_1 , 2); BF(13, 14,-COS3_1 , 2); BF(17, 18, COS3_1 , 2); BF(21, 22,-COS3_1 , 2); BF(25, 26, COS3_1 , 2); BF(29, 30,-COS3_1 , 2); /* pass 5 */ BF1( 0, 1, 2, 3); BF2( 4, 5, 6, 7); BF1( 8, 9, 10, 11); BF2(12, 13, 14, 15); BF1(16, 17, 18, 19); BF2(20, 21, 22, 23); BF1(24, 25, 26, 27); BF2(28, 29, 30, 31); /* pass 6 */ ADD( 8, 12); ADD(12, 10); ADD(10, 14); ADD(14, 9); ADD( 9, 13); ADD(13, 11); ADD(11, 15); out[ 0] = val0; out[16] = val1; out[ 8] = val2; out[24] = val3; out[ 4] = val4; out[20] = val5; out[12] = val6; out[28] = val7; out[ 2] = val8; out[18] = val9; out[10] = val10; out[26] = val11; out[ 6] = val12; out[22] = val13; out[14] = val14; out[30] = val15; ADD(24, 28); ADD(28, 26); ADD(26, 30); ADD(30, 25); ADD(25, 29); ADD(29, 27); ADD(27, 31); out[ 1] = val16 + val24; out[17] = val17 + val25; out[ 9] = val18 + val26; out[25] = val19 + val27; out[ 5] = val20 + val28; out[21] = val21 + val29; out[13] = val22 + val30; out[29] = val23 + val31; out[ 3] = val24 + val20; out[19] = val25 + val21; out[11] = val26 + val22; out[27] = val27 + val23; out[ 7] = val28 + val18; out[23] = val29 + val19; out[15] = val30 + val17; out[31] = val31; }