/* * Floating point AAN IDCT * Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at> * * 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 */ #include "faanidct.h" #include "libavutil/common.h" /* To allow switching to double. */ typedef float FLOAT; #define B0 1.0000000000000000000000 #define B1 1.3870398453221474618216 // cos(pi*1/16)sqrt(2) #define B2 1.3065629648763765278566 // cos(pi*2/16)sqrt(2) #define B3 1.1758756024193587169745 // cos(pi*3/16)sqrt(2) #define B4 1.0000000000000000000000 // cos(pi*4/16)sqrt(2) #define B5 0.7856949583871021812779 // cos(pi*5/16)sqrt(2) #define B6 0.5411961001461969843997 // cos(pi*6/16)sqrt(2) #define B7 0.2758993792829430123360 // cos(pi*7/16)sqrt(2) #define A4 0.70710678118654752438 // cos(pi*4/16) #define A2 0.92387953251128675613 // cos(pi*2/16) static const FLOAT prescale[64]={ B0*B0/8, B0*B1/8, B0*B2/8, B0*B3/8, B0*B4/8, B0*B5/8, B0*B6/8, B0*B7/8, B1*B0/8, B1*B1/8, B1*B2/8, B1*B3/8, B1*B4/8, B1*B5/8, B1*B6/8, B1*B7/8, B2*B0/8, B2*B1/8, B2*B2/8, B2*B3/8, B2*B4/8, B2*B5/8, B2*B6/8, B2*B7/8, B3*B0/8, B3*B1/8, B3*B2/8, B3*B3/8, B3*B4/8, B3*B5/8, B3*B6/8, B3*B7/8, B4*B0/8, B4*B1/8, B4*B2/8, B4*B3/8, B4*B4/8, B4*B5/8, B4*B6/8, B4*B7/8, B5*B0/8, B5*B1/8, B5*B2/8, B5*B3/8, B5*B4/8, B5*B5/8, B5*B6/8, B5*B7/8, B6*B0/8, B6*B1/8, B6*B2/8, B6*B3/8, B6*B4/8, B6*B5/8, B6*B6/8, B6*B7/8, B7*B0/8, B7*B1/8, B7*B2/8, B7*B3/8, B7*B4/8, B7*B5/8, B7*B6/8, B7*B7/8, }; static inline void p8idct(int16_t data[64], FLOAT temp[64], uint8_t *dest, ptrdiff_t stride, int x, int y, int type) { int i; FLOAT s04, d04, s17, d17, s26, d26, s53, d53; FLOAT os07, os16, os25, os34; FLOAT od07, od16, od25, od34; for(i=0; i<y*8; i+=y){ s17= temp[1*x + i] + temp[7*x + i]; d17= temp[1*x + i] - temp[7*x + i]; s53= temp[5*x + i] + temp[3*x + i]; d53= temp[5*x + i] - temp[3*x + i]; od07= s17 + s53; od25= (s17 - s53)*(2*A4); od34= d17*(2*(B6-A2)) - d53*(2*A2); od16= d53*(2*(A2-B2)) + d17*(2*A2); od16 -= od07; od25 -= od16; od34 += od25; s26 = temp[2*x + i] + temp[6*x + i]; d26 = temp[2*x + i] - temp[6*x + i]; d26*= 2*A4; d26-= s26; s04= temp[0*x + i] + temp[4*x + i]; d04= temp[0*x + i] - temp[4*x + i]; os07= s04 + s26; os34= s04 - s26; os16= d04 + d26; os25= d04 - d26; if(type==0){ temp[0*x + i]= os07 + od07; temp[7*x + i]= os07 - od07; temp[1*x + i]= os16 + od16; temp[6*x + i]= os16 - od16; temp[2*x + i]= os25 + od25; temp[5*x + i]= os25 - od25; temp[3*x + i]= os34 - od34; temp[4*x + i]= os34 + od34; }else if(type==1){ data[0*x + i]= lrintf(os07 + od07); data[7*x + i]= lrintf(os07 - od07); data[1*x + i]= lrintf(os16 + od16); data[6*x + i]= lrintf(os16 - od16); data[2*x + i]= lrintf(os25 + od25); data[5*x + i]= lrintf(os25 - od25); data[3*x + i]= lrintf(os34 - od34); data[4*x + i]= lrintf(os34 + od34); }else if(type==2){ dest[0*stride + i]= av_clip_uint8(((int)dest[0*stride + i]) + lrintf(os07 + od07)); dest[7*stride + i]= av_clip_uint8(((int)dest[7*stride + i]) + lrintf(os07 - od07)); dest[1*stride + i]= av_clip_uint8(((int)dest[1*stride + i]) + lrintf(os16 + od16)); dest[6*stride + i]= av_clip_uint8(((int)dest[6*stride + i]) + lrintf(os16 - od16)); dest[2*stride + i]= av_clip_uint8(((int)dest[2*stride + i]) + lrintf(os25 + od25)); dest[5*stride + i]= av_clip_uint8(((int)dest[5*stride + i]) + lrintf(os25 - od25)); dest[3*stride + i]= av_clip_uint8(((int)dest[3*stride + i]) + lrintf(os34 - od34)); dest[4*stride + i]= av_clip_uint8(((int)dest[4*stride + i]) + lrintf(os34 + od34)); }else{ dest[0*stride + i]= av_clip_uint8(lrintf(os07 + od07)); dest[7*stride + i]= av_clip_uint8(lrintf(os07 - od07)); dest[1*stride + i]= av_clip_uint8(lrintf(os16 + od16)); dest[6*stride + i]= av_clip_uint8(lrintf(os16 - od16)); dest[2*stride + i]= av_clip_uint8(lrintf(os25 + od25)); dest[5*stride + i]= av_clip_uint8(lrintf(os25 - od25)); dest[3*stride + i]= av_clip_uint8(lrintf(os34 - od34)); dest[4*stride + i]= av_clip_uint8(lrintf(os34 + od34)); } } } void ff_faanidct(int16_t block[64]){ FLOAT temp[64]; int i; emms_c(); for(i=0; i<64; i++) temp[i] = block[i] * prescale[i]; p8idct(block, temp, NULL, 0, 1, 8, 0); p8idct(block, temp, NULL, 0, 8, 1, 1); } void ff_faanidct_add(uint8_t *dest, ptrdiff_t line_size, int16_t block[64]) { FLOAT temp[64]; int i; emms_c(); for(i=0; i<64; i++) temp[i] = block[i] * prescale[i]; p8idct(block, temp, NULL, 0, 1, 8, 0); p8idct(NULL , temp, dest, line_size, 8, 1, 2); } void ff_faanidct_put(uint8_t *dest, ptrdiff_t line_size, int16_t block[64]) { FLOAT temp[64]; int i; emms_c(); for(i=0; i<64; i++) temp[i] = block[i] * prescale[i]; p8idct(block, temp, NULL, 0, 1, 8, 0); p8idct(NULL , temp, dest, line_size, 8, 1, 3); }