Hash :
a2e6a9dd
Author :
Date :
2006-02-04T00:00:00
IJG R6b with x86SIMD V1.02 Independent JPEG Group's JPEG software release 6b with x86 SIMD extension for IJG JPEG library version 1.02
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;
; jidctint.asm - accurate integer IDCT (non-SIMD)
;
; x86 SIMD extension for IJG JPEG library
; Copyright (C) 1999-2006, MIYASAKA Masaru.
; For conditions of distribution and use, see copyright notice in jsimdext.inc
;
; This file should be assembled with NASM (Netwide Assembler),
; can *not* be assembled with Microsoft's MASM or any compatible
; assembler (including Borland's Turbo Assembler).
; NASM is available from http://nasm.sourceforge.net/ or
; http://sourceforge.net/project/showfiles.php?group_id=6208
;
; This file contains a slow-but-accurate integer implementation of the
; inverse DCT (Discrete Cosine Transform). The following code is based
; directly on the IJG's original jidctint.c; see the jidctint.c for
; more details.
;
; Last Modified : October 17, 2004
;
; [TAB8]
%include "jsimdext.inc"
%include "jdct.inc"
%ifdef DCT_ISLOW_SUPPORTED
; This module is specialized to the case DCTSIZE = 8.
;
%if DCTSIZE != 8
%error "Sorry, this code only copes with 8x8 DCTs."
%endif
; --------------------------------------------------------------------------
; Descale and correctly round a DWORD value that's scaled by N bits.
;
%macro descale 2
%if (%2)<=7
add %1, byte (1<<((%2)-1)) ; add reg32,imm8
%else
add %1, (1<<((%2)-1)) ; add reg32,imm32
%endif
sar %1,%2
%endmacro
; --------------------------------------------------------------------------
%define CONST_BITS 13
%define PASS1_BITS 2
%if CONST_BITS == 13
F_0_298 equ 2446 ; FIX(0.298631336)
F_0_390 equ 3196 ; FIX(0.390180644)
F_0_541 equ 4433 ; FIX(0.541196100)
F_0_765 equ 6270 ; FIX(0.765366865)
F_0_899 equ 7373 ; FIX(0.899976223)
F_1_175 equ 9633 ; FIX(1.175875602)
F_1_501 equ 12299 ; FIX(1.501321110)
F_1_847 equ 15137 ; FIX(1.847759065)
F_1_961 equ 16069 ; FIX(1.961570560)
F_2_053 equ 16819 ; FIX(2.053119869)
F_2_562 equ 20995 ; FIX(2.562915447)
F_3_072 equ 25172 ; FIX(3.072711026)
%else
; NASM cannot do compile-time arithmetic on floating-point constants.
%define DESCALE(x,n) (((x)+(1<<((n)-1)))>>(n))
F_0_298 equ DESCALE( 320652955,30-CONST_BITS) ; FIX(0.298631336)
F_0_390 equ DESCALE( 418953276,30-CONST_BITS) ; FIX(0.390180644)
F_0_541 equ DESCALE( 581104887,30-CONST_BITS) ; FIX(0.541196100)
F_0_765 equ DESCALE( 821806413,30-CONST_BITS) ; FIX(0.765366865)
F_0_899 equ DESCALE( 966342111,30-CONST_BITS) ; FIX(0.899976223)
F_1_175 equ DESCALE(1262586813,30-CONST_BITS) ; FIX(1.175875602)
F_1_501 equ DESCALE(1612031267,30-CONST_BITS) ; FIX(1.501321110)
F_1_847 equ DESCALE(1984016188,30-CONST_BITS) ; FIX(1.847759065)
F_1_961 equ DESCALE(2106220350,30-CONST_BITS) ; FIX(1.961570560)
F_2_053 equ DESCALE(2204520673,30-CONST_BITS) ; FIX(2.053119869)
F_2_562 equ DESCALE(2751909506,30-CONST_BITS) ; FIX(2.562915447)
F_3_072 equ DESCALE(3299298341,30-CONST_BITS) ; FIX(3.072711026)
%endif
; --------------------------------------------------------------------------
SECTION SEG_TEXT
BITS 32
;
; Perform dequantization and inverse DCT on one block of coefficients.
;
; GLOBAL(void)
; jpeg_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr,
; JCOEFPTR coef_block,
; JSAMPARRAY output_buf, JDIMENSION output_col)
;
%define cinfo(b) (b)+8 ; j_decompress_ptr cinfo
%define compptr(b) (b)+12 ; jpeg_component_info * compptr
%define coef_block(b) (b)+16 ; JCOEFPTR coef_block
%define output_buf(b) (b)+20 ; JSAMPARRAY output_buf
%define output_col(b) (b)+24 ; JDIMENSION output_col
%define range_limit ebp-SIZEOF_POINTER ; JSAMPLE * range_limit
%define ptr range_limit-SIZEOF_POINTER ; void * ptr
%define workspace ptr-DCTSIZE2*SIZEOF_INT
; int workspace[DCTSIZE2]
align 16
global EXTN(jpeg_idct_islow)
EXTN(jpeg_idct_islow):
push ebp
mov ebp,esp
lea esp, [workspace]
push ebx
; push ecx ; need not be preserved
; push edx ; need not be preserved
push esi
push edi
; ---- Pass 1: process columns from input, store into work array.
mov edx, POINTER [compptr(ebp)]
mov edx, POINTER [jcompinfo_dct_table(edx)] ; quantptr
mov esi, JCOEFPTR [coef_block(ebp)] ; inptr
lea edi, [workspace] ; int * wsptr
mov ecx, DCTSIZE ; ctr
alignx 16,7
.columnloop:
mov ax, JCOEF [COL(1,esi,SIZEOF_JCOEF)]
or ax, JCOEF [COL(2,esi,SIZEOF_JCOEF)]
jnz short .columnDCT
mov bx, JCOEF [COL(3,esi,SIZEOF_JCOEF)]
mov ax, JCOEF [COL(4,esi,SIZEOF_JCOEF)]
or bx, JCOEF [COL(5,esi,SIZEOF_JCOEF)]
or ax, JCOEF [COL(6,esi,SIZEOF_JCOEF)]
or bx, JCOEF [COL(7,esi,SIZEOF_JCOEF)]
or ax,bx
jnz short .columnDCT
; -- AC terms all zero
mov ax, JCOEF [COL(0,esi,SIZEOF_JCOEF)]
imul ax, ISLOW_MULT_TYPE [COL(0,edx,SIZEOF_ISLOW_MULT_TYPE)]
cwde
sal eax,PASS1_BITS
mov INT [COL(0,edi,SIZEOF_INT)], eax
mov INT [COL(1,edi,SIZEOF_INT)], eax
mov INT [COL(2,edi,SIZEOF_INT)], eax
mov INT [COL(3,edi,SIZEOF_INT)], eax
mov INT [COL(4,edi,SIZEOF_INT)], eax
mov INT [COL(5,edi,SIZEOF_INT)], eax
mov INT [COL(6,edi,SIZEOF_INT)], eax
mov INT [COL(7,edi,SIZEOF_INT)], eax
jmp near .nextcolumn
alignx 16,7
.columnDCT:
push ecx ; ctr
push esi ; coef_block
push edx ; quantptr
mov POINTER [ptr], edi ; wsptr
; -- Even part
movsx eax, JCOEF [COL(0,esi,SIZEOF_JCOEF)]
movsx ecx, JCOEF [COL(4,esi,SIZEOF_JCOEF)]
imul ax, ISLOW_MULT_TYPE [COL(0,edx,SIZEOF_ISLOW_MULT_TYPE)]
imul cx, ISLOW_MULT_TYPE [COL(4,edx,SIZEOF_ISLOW_MULT_TYPE)]
movsx ebx, JCOEF [COL(2,esi,SIZEOF_JCOEF)]
movsx edi, JCOEF [COL(6,esi,SIZEOF_JCOEF)]
imul bx, ISLOW_MULT_TYPE [COL(2,edx,SIZEOF_ISLOW_MULT_TYPE)]
imul di, ISLOW_MULT_TYPE [COL(6,edx,SIZEOF_ISLOW_MULT_TYPE)]
lea edx,[eax+ecx]
sub eax,ecx
sal edx,CONST_BITS ; edx=tmp0
sal eax,CONST_BITS ; eax=tmp1
lea ecx,[ebx+edi]
imul ecx,(F_0_541) ; ecx=z1
imul ebx,(F_0_765) ; ebx=MULTIPLY(z2,FIX_0_765366865)
imul edi,(-F_1_847) ; edi=MULTIPLY(z3,-FIX_1_847759065)
add ebx,ecx ; ebx=tmp3
add edi,ecx ; edi=tmp2
lea ecx,[edx+ebx] ; ecx=tmp10
sub edx,ebx ; edx=tmp13
lea ebx,[eax+edi] ; ebx=tmp11
sub eax,edi ; eax=tmp12
push edx ; tmp13
push eax ; tmp12
push ebx ; tmp11
push ecx ; tmp10
; -- Odd part
mov edx, POINTER [esp+16] ; quantptr
movsx eax, JCOEF [COL(1,esi,SIZEOF_JCOEF)]
movsx edi, JCOEF [COL(3,esi,SIZEOF_JCOEF)]
imul ax, ISLOW_MULT_TYPE [COL(1,edx,SIZEOF_ISLOW_MULT_TYPE)]
imul di, ISLOW_MULT_TYPE [COL(3,edx,SIZEOF_ISLOW_MULT_TYPE)]
movsx ecx, JCOEF [COL(5,esi,SIZEOF_JCOEF)]
movsx ebx, JCOEF [COL(7,esi,SIZEOF_JCOEF)]
imul cx, ISLOW_MULT_TYPE [COL(5,edx,SIZEOF_ISLOW_MULT_TYPE)]
imul bx, ISLOW_MULT_TYPE [COL(7,edx,SIZEOF_ISLOW_MULT_TYPE)]
push eax ; eax=tmp3
push edi ; edi=tmp2
push ecx ; ecx=tmp1
push ebx ; ebx=tmp0
lea esi,[ebx+edi] ; esi=z3
lea edx,[ecx+eax] ; edx=z4
add ebx,eax ; ebx=z1
add ecx,edi ; ecx=z2
lea eax,[esi+edx]
imul eax,(F_1_175) ; eax=z5
imul esi,(-F_1_961) ; esi=z3(=MULTIPLY(z3,-FIX_1_961570560))
imul edx,(-F_0_390) ; edx=z4(=MULTIPLY(z4,-FIX_0_390180644))
imul ebx,(-F_0_899) ; ebx=z1(=MULTIPLY(z1,-FIX_0_899976223))
imul ecx,(-F_2_562) ; ecx=z2(=MULTIPLY(z2,-FIX_2_562915447))
add esi,eax ; esi=z3(=z3+z5)
add edx,eax ; edx=z4(=z4+z5)
lea edi,[esi+ebx] ; edi=z1+z3
lea eax,[edx+ecx] ; eax=z2+z4
add esi,ecx ; esi=z2+z3
add edx,ebx ; edx=z1+z4
pop ecx ; ecx=tmp0
pop ebx ; ebx=tmp1
imul ecx,(F_0_298) ; ecx=tmp0(=MULTIPLY(tmp0,FIX_0_298631336))
imul ebx,(F_2_053) ; ebx=tmp1(=MULTIPLY(tmp1,FIX_2_053119869))
add edi,ecx ; edi=tmp0(=tmp0+z1+z3)
add eax,ebx ; eax=tmp1(=tmp1+z2+z4)
pop ecx ; ecx=tmp2
pop ebx ; ebx=tmp3
imul ecx,(F_3_072) ; ecx=tmp2(=MULTIPLY(tmp2,FIX_3_072711026))
imul ebx,(F_1_501) ; ebx=tmp3(=MULTIPLY(tmp3,FIX_1_501321110))
add esi,ecx ; esi=tmp2(=tmp2+z2+z3)
add edx,ebx ; edx=tmp3(=tmp3+z1+z4)
; -- Final output stage
pop ecx ; ecx=tmp10
pop ebx ; ebx=tmp11
push eax ; tmp1
push edi ; tmp0
lea eax,[ecx+edx] ; eax=data0(=tmp10+tmp3)
sub ecx,edx ; ecx=data7(=tmp10-tmp3)
lea edx,[ebx+esi] ; edx=data1(=tmp11+tmp2)
sub ebx,esi ; ebx=data6(=tmp11-tmp2)
mov edi, POINTER [ptr] ; edi=wsptr
descale eax,(CONST_BITS-PASS1_BITS)
descale ecx,(CONST_BITS-PASS1_BITS)
descale edx,(CONST_BITS-PASS1_BITS)
descale ebx,(CONST_BITS-PASS1_BITS)
mov INT [COL(0,edi,SIZEOF_INT)], eax
mov INT [COL(7,edi,SIZEOF_INT)], ecx
mov INT [COL(1,edi,SIZEOF_INT)], edx
mov INT [COL(6,edi,SIZEOF_INT)], ebx
pop esi ; esi=tmp0
pop eax ; eax=tmp1
pop ecx ; ecx=tmp12
pop edx ; edx=tmp13
lea ebx,[ecx+eax] ; ebx=data2(=tmp12+tmp1)
sub ecx,eax ; ecx=data5(=tmp12-tmp1)
lea eax,[edx+esi] ; eax=data3(=tmp13+tmp0)
sub edx,esi ; edx=data4(=tmp13-tmp0)
descale ebx,(CONST_BITS-PASS1_BITS)
descale ecx,(CONST_BITS-PASS1_BITS)
descale eax,(CONST_BITS-PASS1_BITS)
descale edx,(CONST_BITS-PASS1_BITS)
mov INT [COL(2,edi,SIZEOF_INT)], ebx
mov INT [COL(5,edi,SIZEOF_INT)], ecx
mov INT [COL(3,edi,SIZEOF_INT)], eax
mov INT [COL(4,edi,SIZEOF_INT)], edx
pop edx ; quantptr
pop esi ; coef_block
pop ecx ; ctr
.nextcolumn:
add esi, byte SIZEOF_JCOEF ; advance pointers to next column
add edx, byte SIZEOF_ISLOW_MULT_TYPE
add edi, byte SIZEOF_INT
dec ecx
jnz near .columnloop
; ---- Pass 2: process rows from work array, store into output array.
mov eax, POINTER [cinfo(ebp)]
mov eax, POINTER [jdstruct_sample_range_limit(eax)]
sub eax, byte -CENTERJSAMPLE*SIZEOF_JSAMPLE ; JSAMPLE * range_limit
mov POINTER [range_limit], eax
lea esi, [workspace] ; int * wsptr
mov edi, JSAMPARRAY [output_buf(ebp)] ; (JSAMPROW *)
mov ecx, DCTSIZE ; ctr
alignx 16,7
.rowloop:
push edi
mov edi, JSAMPROW [edi] ; (JSAMPLE *)
add edi, JDIMENSION [output_col(ebp)] ; edi=outptr
%ifndef NO_ZERO_ROW_TEST
mov eax, INT [ROW(1,esi,SIZEOF_INT)]
or eax, INT [ROW(2,esi,SIZEOF_INT)]
jnz short .rowDCT
mov ebx, INT [ROW(3,esi,SIZEOF_INT)]
mov eax, INT [ROW(4,esi,SIZEOF_INT)]
or ebx, INT [ROW(5,esi,SIZEOF_INT)]
or eax, INT [ROW(6,esi,SIZEOF_INT)]
or ebx, INT [ROW(7,esi,SIZEOF_INT)]
or eax,ebx
jnz short .rowDCT
; -- AC terms all zero
mov eax, INT [ROW(0,esi,SIZEOF_INT)]
mov edx, POINTER [range_limit] ; (JSAMPLE *)
descale eax,(PASS1_BITS+3)
and eax,RANGE_MASK
mov al, JSAMPLE [edx+eax*SIZEOF_JSAMPLE]
mov JSAMPLE [edi+0*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+1*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+2*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+3*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+4*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+5*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+6*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+7*SIZEOF_JSAMPLE], al
jmp near .nextrow
alignx 16,7
%endif
.rowDCT:
push esi ; wsptr
push ecx ; ctr
mov POINTER [ptr], edi ; outptr
; -- Even part
mov eax, INT [ROW(0,esi,SIZEOF_INT)]
mov ebx, INT [ROW(2,esi,SIZEOF_INT)]
mov ecx, INT [ROW(4,esi,SIZEOF_INT)]
mov edi, INT [ROW(6,esi,SIZEOF_INT)]
lea edx,[eax+ecx]
sub eax,ecx
sal edx,CONST_BITS ; edx=tmp0
sal eax,CONST_BITS ; eax=tmp1
lea ecx,[ebx+edi]
imul ecx,(F_0_541) ; ecx=z1
imul ebx,(F_0_765) ; ebx=MULTIPLY(z2,FIX_0_765366865)
imul edi,(-F_1_847) ; edi=MULTIPLY(z3,-FIX_1_847759065)
add ebx,ecx ; ebx=tmp3
add edi,ecx ; edi=tmp2
lea ecx,[edx+ebx] ; ecx=tmp10
sub edx,ebx ; edx=tmp13
lea ebx,[eax+edi] ; ebx=tmp11
sub eax,edi ; eax=tmp12
push edx ; tmp13
push eax ; tmp12
push ebx ; tmp11
push ecx ; tmp10
; -- Odd part
mov eax, INT [ROW(1,esi,SIZEOF_INT)]
mov edi, INT [ROW(3,esi,SIZEOF_INT)]
mov ecx, INT [ROW(5,esi,SIZEOF_INT)]
mov ebx, INT [ROW(7,esi,SIZEOF_INT)]
push eax ; eax=tmp3
push edi ; edi=tmp2
push ecx ; ecx=tmp1
push ebx ; ebx=tmp0
lea esi,[ebx+edi] ; esi=z3
lea edx,[ecx+eax] ; edx=z4
add ebx,eax ; ebx=z1
add ecx,edi ; ecx=z2
lea eax,[esi+edx]
imul eax,(F_1_175) ; eax=z5
imul esi,(-F_1_961) ; esi=z3(=MULTIPLY(z3,-FIX_1_961570560))
imul edx,(-F_0_390) ; edx=z4(=MULTIPLY(z4,-FIX_0_390180644))
imul ebx,(-F_0_899) ; ebx=z1(=MULTIPLY(z1,-FIX_0_899976223))
imul ecx,(-F_2_562) ; ecx=z2(=MULTIPLY(z2,-FIX_2_562915447))
add esi,eax ; esi=z3(=z3+z5)
add edx,eax ; edx=z4(=z4+z5)
lea edi,[esi+ebx] ; edi=z1+z3
lea eax,[edx+ecx] ; eax=z2+z4
add esi,ecx ; esi=z2+z3
add edx,ebx ; edx=z1+z4
pop ecx ; ecx=tmp0
pop ebx ; ebx=tmp1
imul ecx,(F_0_298) ; ecx=tmp0(=MULTIPLY(tmp0,FIX_0_298631336))
imul ebx,(F_2_053) ; ebx=tmp1(=MULTIPLY(tmp1,FIX_2_053119869))
add edi,ecx ; edi=tmp0(=tmp0+z1+z3)
add eax,ebx ; eax=tmp1(=tmp1+z2+z4)
pop ecx ; ecx=tmp2
pop ebx ; ebx=tmp3
imul ecx,(F_3_072) ; ecx=tmp2(=MULTIPLY(tmp2,FIX_3_072711026))
imul ebx,(F_1_501) ; ebx=tmp3(=MULTIPLY(tmp3,FIX_1_501321110))
add esi,ecx ; esi=tmp2(=tmp2+z2+z3)
add edx,ebx ; edx=tmp3(=tmp3+z1+z4)
; -- Final output stage
pop ecx ; ecx=tmp10
pop ebx ; ebx=tmp11
push eax ; tmp1
push edi ; tmp0
lea eax,[ecx+edx] ; eax=data0(=tmp10+tmp3)
sub ecx,edx ; ecx=data7(=tmp10-tmp3)
lea edx,[ebx+esi] ; edx=data1(=tmp11+tmp2)
sub ebx,esi ; ebx=data6(=tmp11-tmp2)
mov esi, POINTER [range_limit] ; (JSAMPLE *)
descale eax,(CONST_BITS+PASS1_BITS+3)
descale ecx,(CONST_BITS+PASS1_BITS+3)
descale edx,(CONST_BITS+PASS1_BITS+3)
descale ebx,(CONST_BITS+PASS1_BITS+3)
mov edi, POINTER [ptr] ; edi=outptr
and eax,RANGE_MASK
and ecx,RANGE_MASK
and edx,RANGE_MASK
and ebx,RANGE_MASK
mov al, JSAMPLE [esi+eax*SIZEOF_JSAMPLE]
mov cl, JSAMPLE [esi+ecx*SIZEOF_JSAMPLE]
mov dl, JSAMPLE [esi+edx*SIZEOF_JSAMPLE]
mov bl, JSAMPLE [esi+ebx*SIZEOF_JSAMPLE]
mov JSAMPLE [edi+0*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+7*SIZEOF_JSAMPLE], cl
mov JSAMPLE [edi+1*SIZEOF_JSAMPLE], dl
mov JSAMPLE [edi+6*SIZEOF_JSAMPLE], bl
pop esi ; esi=tmp0
pop eax ; eax=tmp1
pop ecx ; ecx=tmp12
pop edx ; edx=tmp13
lea ebx,[ecx+eax] ; ebx=data2(=tmp12+tmp1)
sub ecx,eax ; ecx=data5(=tmp12-tmp1)
lea eax,[edx+esi] ; eax=data3(=tmp13+tmp0)
sub edx,esi ; edx=data4(=tmp13-tmp0)
mov esi, POINTER [range_limit] ; (JSAMPLE *)
descale ebx,(CONST_BITS+PASS1_BITS+3)
descale ecx,(CONST_BITS+PASS1_BITS+3)
descale eax,(CONST_BITS+PASS1_BITS+3)
descale edx,(CONST_BITS+PASS1_BITS+3)
and ebx,RANGE_MASK
and ecx,RANGE_MASK
and eax,RANGE_MASK
and edx,RANGE_MASK
mov bl, JSAMPLE [esi+ebx*SIZEOF_JSAMPLE]
mov cl, JSAMPLE [esi+ecx*SIZEOF_JSAMPLE]
mov al, JSAMPLE [esi+eax*SIZEOF_JSAMPLE]
mov dl, JSAMPLE [esi+edx*SIZEOF_JSAMPLE]
mov JSAMPLE [edi+2*SIZEOF_JSAMPLE], bl
mov JSAMPLE [edi+5*SIZEOF_JSAMPLE], cl
mov JSAMPLE [edi+3*SIZEOF_JSAMPLE], al
mov JSAMPLE [edi+4*SIZEOF_JSAMPLE], dl
pop ecx ; ctr
pop esi ; wsptr
.nextrow:
pop edi
add esi, byte DCTSIZE*SIZEOF_INT ; advance pointer to next row
add edi, byte SIZEOF_JSAMPROW
dec ecx
jnz near .rowloop
pop edi
pop esi
; pop edx ; need not be preserved
; pop ecx ; need not be preserved
pop ebx
mov esp,ebp
pop ebp
ret
%endif ; DCT_ISLOW_SUPPORTED