📄 idct_mmx.asm
字号:
;/****************************************************************************; *; * XVID MPEG-4 VIDEO CODEC; * - MMX and XMM forward discrete cosine transform -; *; * Copyright(C) 2001 Peter Ross <pross@xvid.org>; * 2004 Andre Werthmann <wertmann@aei.mpg.de>; *; * This program is free software; you can redistribute it and/or modify it; * under the terms of the GNU General Public License as published by; * the Free Software Foundation; either version 2 of the License, or; * (at your option) any later version.; *; * This program 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 General Public License for more details.; *; * You should have received a copy of the GNU General Public License; * along with this program; if not, write to the Free Software; * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA; *; * $Id: idct_mmx.asm,v 1.1 2005/01/05 23:02:15 edgomez Exp $; *; ***************************************************************************/; ****************************************************************************;; Originally provided by Intel at AP-922; http://developer.intel.com/vtune/cbts/strmsimd/922down.htm; (See more app notes at http://developer.intel.com/vtune/cbts/strmsimd/appnotes.htm); but in a limited edition.; New macro implements a column part for precise iDCT; The routine precision now satisfies IEEE standard 1180-1990.;; Copyright(C) 2000-2001 Peter Gubanov <peter@elecard.net.ru>; Rounding trick Copyright(C) 2000 Michel Lespinasse <walken@zoy.org>;; http://www.elecard.com/peter/idct.html; http://www.linuxvideo.org/mpeg2dec/;; ***************************************************************************/;; These examples contain code fragments for first stage iDCT 8x8; (for rows) and first stage DCT 8x8 (for columns);BITS 64;=============================================================================; Macros and other preprocessor constants;=============================================================================%macro cglobal 1 %ifdef PREFIX %ifdef MARK_FUNCS global _%1:function %1.endfunc-%1 %define %1 _%1:function %1.endfunc-%1 %else global _%1 %define %1 _%1 %endif %else %ifdef MARK_FUNCS global %1:function %1.endfunc-%1 %else global %1 %endif %endif%endmacro%define BITS_INV_ACC 5 ; 4 or 5 for IEEE%define SHIFT_INV_ROW 16 - BITS_INV_ACC%define SHIFT_INV_COL 1 + BITS_INV_ACC%define RND_INV_ROW 1024 * (6 - BITS_INV_ACC) ; 1 << (SHIFT_INV_ROW-1)%define RND_INV_COL 16 * (BITS_INV_ACC - 3) ; 1 << (SHIFT_INV_COL-1)%define RND_INV_CORR RND_INV_COL - 1 ; correction -1.0 and round%define BITS_FRW_ACC 3 ; 2 or 3 for accuracy%define SHIFT_FRW_COL BITS_FRW_ACC%define SHIFT_FRW_ROW BITS_FRW_ACC + 17%define RND_FRW_ROW 262144*(BITS_FRW_ACC - 1) ; 1 << (SHIFT_FRW_ROW-1);=============================================================================; Local Data (Read Only);=============================================================================%ifdef FORMAT_COFFSECTION .rodata%elseSECTION .rodata align=16%endif;-----------------------------------------------------------------------------; Various memory constants (trigonometric values or rounding values);-----------------------------------------------------------------------------ALIGN 16one_corr: dw 1, 1, 1, 1round_inv_row: dd RND_INV_ROW, RND_INV_ROWround_inv_col: dw RND_INV_COL, RND_INV_COL, RND_INV_COL, RND_INV_COLround_inv_corr: dw RND_INV_CORR, RND_INV_CORR, RND_INV_CORR, RND_INV_CORRround_frw_row: dd RND_FRW_ROW, RND_FRW_ROWtg_1_16: dw 13036, 13036, 13036, 13036 ; tg * (2<<16) + 0.5tg_2_16: dw 27146, 27146, 27146, 27146 ; tg * (2<<16) + 0.5tg_3_16: dw -21746, -21746, -21746, -21746 ; tg * (2<<16) + 0.5cos_4_16: dw -19195, -19195, -19195, -19195 ; cos * (2<<16) + 0.5ocos_4_16: dw 23170, 23170, 23170, 23170 ; cos * (2<<15) + 0.5otg_3_16: dw 21895, 21895, 21895, 21895 ; tg * (2<<16) + 0.5%if SHIFT_INV_ROW == 12 ; assume SHIFT_INV_ROW == 12rounder_0: dd 65536, 65536rounder_4: dd 0, 0rounder_1: dd 7195, 7195rounder_7 dd 1024, 1024rounder_2: dd 4520, 4520rounder_6: dd 1024, 1024rounder_3: dd 2407, 2407rounder_5: dd 240, 240%elif SHIFT_INV_ROW == 11 ; assume SHIFT_INV_ROW == 11rounder_0: dd 65536, 65536rounder_4: dd 0, 0rounder_1: dd 3597, 3597rounder_7: dd 512, 512rounder_2: dd 2260, 2260rounder_6: dd 512, 512rounder_3: dd 1203, 1203rounder_5: dd 120, 120%else%error invalid SHIFT_INV_ROW%endif;-----------------------------------------------------------------------------;; The first stage iDCT 8x8 - inverse DCTs of rows;;-----------------------------------------------------------------------------; The 8-point inverse DCT direct algorithm;-----------------------------------------------------------------------------;; static const short w[32] = {; FIX(cos_4_16), FIX(cos_2_16), FIX(cos_4_16), FIX(cos_6_16),; FIX(cos_4_16), FIX(cos_6_16), -FIX(cos_4_16), -FIX(cos_2_16),; FIX(cos_4_16), -FIX(cos_6_16), -FIX(cos_4_16), FIX(cos_2_16),; FIX(cos_4_16), -FIX(cos_2_16), FIX(cos_4_16), -FIX(cos_6_16),; FIX(cos_1_16), FIX(cos_3_16), FIX(cos_5_16), FIX(cos_7_16),; FIX(cos_3_16), -FIX(cos_7_16), -FIX(cos_1_16), -FIX(cos_5_16),; FIX(cos_5_16), -FIX(cos_1_16), FIX(cos_7_16), FIX(cos_3_16),; FIX(cos_7_16), -FIX(cos_5_16), FIX(cos_3_16), -FIX(cos_1_16) };;; #define DCT_8_INV_ROW(x, y); {; int a0, a1, a2, a3, b0, b1, b2, b3;;; a0 =x[0]*w[0]+x[2]*w[1]+x[4]*w[2]+x[6]*w[3];; a1 =x[0]*w[4]+x[2]*w[5]+x[4]*w[6]+x[6]*w[7];; a2 = x[0] * w[ 8] + x[2] * w[ 9] + x[4] * w[10] + x[6] * w[11];; a3 = x[0] * w[12] + x[2] * w[13] + x[4] * w[14] + x[6] * w[15];; b0 = x[1] * w[16] + x[3] * w[17] + x[5] * w[18] + x[7] * w[19];; b1 = x[1] * w[20] + x[3] * w[21] + x[5] * w[22] + x[7] * w[23];; b2 = x[1] * w[24] + x[3] * w[25] + x[5] * w[26] + x[7] * w[27];; b3 = x[1] * w[28] + x[3] * w[29] + x[5] * w[30] + x[7] * w[31];;; y[0] = SHIFT_ROUND ( a0 + b0 );; y[1] = SHIFT_ROUND ( a1 + b1 );; y[2] = SHIFT_ROUND ( a2 + b2 );; y[3] = SHIFT_ROUND ( a3 + b3 );; y[4] = SHIFT_ROUND ( a3 - b3 );; y[5] = SHIFT_ROUND ( a2 - b2 );; y[6] = SHIFT_ROUND ( a1 - b1 );; y[7] = SHIFT_ROUND ( a0 - b0 );; };;-----------------------------------------------------------------------------;; In this implementation the outputs of the iDCT-1D are multiplied; for rows 0,4 - by cos_4_16,; for rows 1,7 - by cos_1_16,; for rows 2,6 - by cos_2_16,; for rows 3,5 - by cos_3_16; and are shifted to the left for better accuracy;; For the constants used,; FIX(float_const) = (short) (float_const * (1<<15) + 0.5);;-----------------------------------------------------------------------------;-----------------------------------------------------------------------------; Tables for xmm processors;-----------------------------------------------------------------------------; %3 for rows 0,4 - constants are multiplied by cos_4_16tab_i_04_xmm: dw 16384, 21407, 16384, 8867 ; movq-> w05 w04 w01 w00 dw 16384, 8867, -16384, -21407 ; w07 w06 w03 w02 dw 16384, -8867, 16384, -21407 ; w13 w12 w09 w08 dw -16384, 21407, 16384, -8867 ; w15 w14 w11 w10 dw 22725, 19266, 19266, -4520 ; w21 w20 w17 w16 dw 12873, 4520, -22725, -12873 ; w23 w22 w19 w18 dw 12873, -22725, 4520, -12873 ; w29 w28 w25 w24 dw 4520, 19266, 19266, -22725 ; w31 w30 w27 w26; %3 for rows 1,7 - constants are multiplied by cos_1_16tab_i_17_xmm: dw 22725, 29692, 22725, 12299 ; movq-> w05 w04 w01 w00 dw 22725, 12299, -22725, -29692 ; w07 w06 w03 w02 dw 22725, -12299, 22725, -29692 ; w13 w12 w09 w08 dw -22725, 29692, 22725, -12299 ; w15 w14 w11 w10 dw 31521, 26722, 26722, -6270 ; w21 w20 w17 w16 dw 17855, 6270, -31521, -17855 ; w23 w22 w19 w18 dw 17855, -31521, 6270, -17855 ; w29 w28 w25 w24 dw 6270, 26722, 26722, -31521 ; w31 w30 w27 w26; %3 for rows 2,6 - constants are multiplied by cos_2_16tab_i_26_xmm: dw 21407, 27969, 21407, 11585 ; movq-> w05 w04 w01 w00 dw 21407, 11585, -21407, -27969 ; w07 w06 w03 w02 dw 21407, -11585, 21407, -27969 ; w13 w12 w09 w08 dw -21407, 27969, 21407, -11585 ; w15 w14 w11 w10 dw 29692, 25172, 25172, -5906 ; w21 w20 w17 w16 dw 16819, 5906, -29692, -16819 ; w23 w22 w19 w18 dw 16819, -29692, 5906, -16819 ; w29 w28 w25 w24 dw 5906, 25172, 25172, -29692 ; w31 w30 w27 w26; %3 for rows 3,5 - constants are multiplied by cos_3_16tab_i_35_xmm: dw 19266, 25172, 19266, 10426 ; movq-> w05 w04 w01 w00 dw 19266, 10426, -19266, -25172 ; w07 w06 w03 w02 dw 19266, -10426, 19266, -25172 ; w13 w12 w09 w08 dw -19266, 25172, 19266, -10426 ; w15 w14 w11 w10 dw 26722, 22654, 22654, -5315 ; w21 w20 w17 w16 dw 15137, 5315, -26722, -15137 ; w23 w22 w19 w18 dw 15137, -26722, 5315, -15137 ; w29 w28 w25 w24
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -