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UConvert.a
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UConvert.a
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;Photoshop version 1.0.1, file: UConvert.a
; Computer History Museum, www.computerhistory.org
; This material is (C)Copyright 1990 Adobe Systems Inc.
; It may not be distributed to third parties.
; It is licensed for non-commercial use according to
; www.computerhistory.org/softwarelicense/photoshop/
INCLUDE 'Traps.a'
; **********************************************************************
SEG 'ARes'
DeHalftoneRow PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DeHalftoneRow (srcPtr: Ptr;
; dstPtr: Ptr;
; rowBytes: INTEGER;
; cols: INTEGER;
; scale: INTEGER;
; thresTable: TThresTable);
;
; Parameter Offsets
@srcPtr EQU 22
@dstPtr EQU 18
@rowBytes EQU 16
@cols EQU 14
@scale EQU 12
@thresTable EQU 8
; Size of parameters
@params EQU 18
; Save registers
LINK A6,#0
MOVEM.L D3-D7/A2-A3,-(SP)
; D0 = scale - 1
MOVE.W @scale(A6),D0
SUB.W #1,D0
; D1 = bytes per input row
MOVE.W @rowBytes(A6),D1
; A0 is output pointer
MOVE.L @dstPtr(A6),A0
; A1 is threshold table pointer
MOVE.L @thresTable(A6),A1
; Compute an output row
MOVE.L @srcPtr(A6),A2
MOVE.W #7,D2
; Scan through columns
MOVE.W @cols(A6),D3
SUB.W #1,D3
; Map the bits into bytes
@2 CLR.W D7
MOVE.W D0,D4
@3 MOVE.W D0,D5
MOVE.L A2,A3
@4 BTST D2,(A3)
BEQ.S @5
ADD.W #1,D7
@5 ADD.W D1,A3
DBF D5,@4
SUB.W #1,D2
BCC.S @6
ADD.W #1,A2
ADD.W #8,D2
@6 DBF D4,@3
MOVE.B (A1,D7.W),(A0)+
DBF D3,@2
; Clean up and exit
MOVEM.L (SP)+,D3-D7/A2-A3
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
DoCountColors PROC EXPORT
; Calling sequence (Pascal conventions):
;
; FUNCTION DoCountColors (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; size: INTEGER;
; colorTable: Ptr): BOOLEAN;
; Parameter Offsets
@result EQU 26
@rDataPtr EQU 22
@gDataPtr EQU 18
@bDataPtr EQU 14
@size EQU 12
@colorTable EQU 8
; Size of parameters
@params EQU 18
; Save registers
LINK A6,#0
MOVEM.L A2-A4,-(SP)
; A0 is pointer to color table
MOVE.L @colorTable(A6),A0
; A1-A3 are pointers to input channels
MOVE.L @rDataPtr(A6),A1
MOVE.L @gDataPtr(A6),A2
MOVE.L @bDataPtr(A6),A3
; Loop through pixels
MOVE.W @size(A6),D0
SUB.W #1,D0
; Get next pixel value
@2 CLR.L D1
MOVE.B (A3)+,D1
SWAP D1
MOVE.B (A2)+,D1
LSL.W #8,D1
MOVE.B (A1)+,D1
; Test for black or white
TST.L D1
BEQ.S @13
CMP.L #$FFFFFF,D1
BEQ.S @13
; Do a binary search for color
MOVE.L A0,A4
CMP.L $200(A4),D1
BGT.S @3
ADD.W #$200,A4
@3 CMP.L $100(A4),D1
BGT.S @4
ADD.W #$100,A4
@4 CMP.L $80(A4),D1
BGT.S @5
ADD.W #$80,A4
@5 CMP.L $40(A4),D1
BGT.S @6
ADD.W #$40,A4
@6 CMP.L $20(A4),D1
BGT.S @7
ADD.W #$20,A4
@7 CMP.L $10(A4),D1
BGT.S @8
ADD.W #$10,A4
@8 CMP.L $8(A4),D1
BGT.S @9
ADD.W #$8,A4
@9 CMP.L $4(A4),D1
BGT.S @10
ADD.W #$4,A4
@10 CMP.L (A4),D1
BEQ.S @13
BGT.S @11
ADD.W #$4,A4
; Color value was not found, see if table is full
@11 TST.L 1016(A0)
BEQ.S @12
MOVE.B #1,@result(A6)
BRA.S @15
; Insert value into color table
@12 MOVE.L (A4),D2
MOVE.L D1,(A4)+
MOVE.L D2,D1
BNE.S @12
; Move to next pixel
@13 DBF D0,@2
; Success
CLR.B @result(A6)
; Clean up and exit
@15 MOVEM.L (SP)+,A2-A4
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
DoMapColors PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DoMapColors (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; size: INTEGER;
; colorTable: Ptr;
; outDataPtr: Ptr);
; Parameter Offsets
@rDataPtr EQU 26
@gDataPtr EQU 22
@bDataPtr EQU 18
@size EQU 16
@colorTable EQU 12
@outDataPtr EQU 8
; Size of parameters
@params EQU 22
; Save registers
LINK A6,#0
MOVEM.L A2-A5,-(SP)
; Find index of black
MOVE.L @colorTable(A6),A0
MOVE.L A0,A1
@1 TST.L (A1)+
BNE.S @1
MOVE.L A1,D2
SUB.L A0,D2
LSR.W #2,D2
SUB.W #1,D2
; A1-A3 are pointers to input channels
MOVE.L @rDataPtr(A6),A1
MOVE.L @gDataPtr(A6),A2
MOVE.L @bDataPtr(A6),A3
; A5 is pointer to output data
MOVE.L @outDataPtr(A6),A5
; Loop through pixels
MOVE.W @size(A6),D0
SUB.W #1,D0
; Get next pixel value
@2 CLR.L D1
MOVE.B (A3)+,D1
SWAP D1
MOVE.B (A2)+,D1
LSL.W #8,D1
MOVE.B (A1)+,D1
; Test for black
TST.L D1
BNE.S @2A
MOVE.B D2,(A5)+
BRA.S @next
; Test for white
@2A CMP.L #$FFFFFF,D1
BNE.S @2B
CLR.B (A5)+
BRA.S @next
; Do a binary search for color
@2B MOVE.L A0,A4
CMP.L $200(A4),D1
BGT.S @3
ADD.W #$200,A4
@3 CMP.L $100(A4),D1
BGT.S @4
ADD.W #$100,A4
@4 CMP.L $80(A4),D1
BGT.S @5
ADD.W #$80,A4
@5 CMP.L $40(A4),D1
BGT.S @6
ADD.W #$40,A4
@6 CMP.L $20(A4),D1
BGT.S @7
ADD.W #$20,A4
@7 CMP.L $10(A4),D1
BGT.S @8
ADD.W #$10,A4
@8 CMP.L $8(A4),D1
BGT.S @9
ADD.W #$8,A4
@9 CMP.L $4(A4),D1
BGT.S @map
ADD.W #$4,A4
; Compute pixel index
@map MOVE.L A4,D1
SUB.L A0,D1
LSR.W #2,D1
MOVE.B D1,(A5)+
; Move to next pixel
@next DBF D0,@2
; Clean up and exit
@15 MOVEM.L (SP)+,A2-A5
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
DoBuildInverse PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DoBuildInverse (table: Ptr;
; buffer: Ptr;
; step: INTEGER);
; Parameter Offsets
@table EQU 14
@buffer EQU 10
@step EQU 8
; Size of parameters
@params EQU 10
; Save registers
LINK A6,#0
MOVEM.L D2-D3,-(SP)
; Unload parameters
MOVE.L @table(A6),A0
MOVE.L @buffer(A6),A1
MOVE.W @step(A6),D0
; Initialize loop
MOVE.W #31,D1
MOVE.W #255,D3
; Increment current distance unless equal to 255
@1 ADD.B #1,D3
BNE.S @2
SUB.B #1,D3
; Compare distance to existing distance
@2 CMP.B (A1),D3
BHS.S @3
; Current distance is less than existing distance
MOVE.B D2,(A0)
MOVE.B D3,(A1)
BRA.S @4
; Current distance is more than or same as existing distance
@3 MOVE.B (A0),D2
MOVE.B (A1),D3
; Move to next pixel
@4 ADDA.W D0,A0
ADDA.W D0,A1
DBF D1,@1
; Clean up and exit
MOVEM.L (SP)+,D2-D3
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
NoDitherRow PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE NoDitherRow (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; outDataPtr: Ptr;
; table: Ptr;
; count: INTEGER); EXTERNAL;
;
; Parameter Offsets
@rDataPtr EQU 26
@gDataPtr EQU 22
@bDataPtr EQU 18
@outDataPtr EQU 14
@table EQU 10
@count EQU 8
; Size of parameters
@params EQU 22
; Save registers
LINK A6,#0
MOVEM.L A2-A4,-(SP)
; Unload parameters
MOVE.L @rDataPtr(A6),A0
MOVE.L @gDataPtr(A6),A1
MOVE.L @bDataPtr(A6),A2
MOVE.L @outDataPtr(A6),A3
MOVE.L @table(A6),A4
MOVE.W @count(A6),D0
SUB.W #1,D0
; Compute output index
@1 CLR.W D1
MOVE.B (A0)+,D1
LSR.B #3,D1
CLR.W D2
MOVE.B (A1)+,D2
LSR.B #3,D2
LSL.W #5,D2
ADD.W D2,D1
CLR.W D2
MOVE.B (A2)+,D2
LSR.B #3,D2
ROR.W #6,D2
ADD.W D2,D1
MOVE.B (A4,D1.W),(A3)+
DBF D0,@1
; Clean up and exit
MOVEM.L (SP)+,A2-A4
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
; Diffuses the error in and computes the output index
MACRO
DiffuseIn &in,&out
; Add in 3/4 of error
MOVE.W (A2)+,D5
ADD.W D5,&in
ASR.W #2,D5
SUB.W D5,&in
; Clamp to 0..255
BPL.S @1
CLR.W &in
@1 CMP.W #255,&in
BLE.S @2
MOVE.W #255,&in
; Strip off lower 3 bits
@2 MOVE.W &in,&out
LSR.B #3,&out
ENDM
; **********************************************************************
; Diffuses the error out to nearby pixels
MACRO
DiffuseOut ®,&off
; Find 1/4 of error
MOVE.W ®,D7
ASR.W #2,D7
; Diffuse it down and back
ADD.W D7,-6(A3)
; Divide remaining error in half
SUB.W D7,®
ASR.W #1,®
; Diffuse it down and to right
ADD.W ®,(A3)+
ADD.W ®,&off(A2)
ENDM
; **********************************************************************
SEG 'ADoConvert'
DiffuseRGB PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DiffuseRGB (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; outDataPtr: Ptr;
; thisError: Ptr;
; nextError: Ptr;
; table: Ptr;
; LUT: TRGBLookUpTable;
; count: INTEGER);
;
; Parameter Offsets
@rDataPtr EQU 38
@gDataPtr EQU 34
@bDataPtr EQU 30
@outDataPtr EQU 26
@thisError EQU 22
@nextError EQU 18
@table EQU 14
@LUT EQU 10
@count EQU 8
; Size of parameters
@params EQU 34
; Save registers
LINK A6,#0
MOVEM.L D3-D7/A2-A5,-(SP)
; Unload parameters
MOVE.L @outDataPtr(A6),A1
MOVE.L @thisError(A6),A2
MOVE.L @nextError(A6),A3
MOVE.L @table(A6),A4
MOVE.L @LUT(A6),A5
MOVE.W @count(A6),D0
SUB.W #1,D0
; Compute output index
@1 MOVE.L @rDataPtr(A6),A0
ADD.L #1,@rDataPtr(A6)
CLR.W D1
MOVE.B (A0),D1
DiffuseIn D1,D7
MOVE.L @gDataPtr(A6),A0
ADD.L #1,@gDataPtr(A6)
CLR.W D2
MOVE.B (A0),D2
DiffuseIn D2,D6
LSL.W #5,D6
ADD.W D6,D7
MOVE.L @bDataPtr(A6),A0
ADD.L #1,@bDataPtr(A6)
CLR.W D3
MOVE.B (A0),D3
DiffuseIn D3,D6
ROR.W #6,D6
ADD.W D6,D7
; Look up in inverse table
CLR.W D6
MOVE.B (A4,D7.W),D6
; Save output value
MOVE.B D6,(A1)+
; Subtract the output value from goal
CLR.W D7
MOVE.B (A5,D6.W),D7
SUB.W D7,D1
ADD.W #256,D6
MOVE.B (A5,D6.W),D7
SUB.W D7,D2
ADD.W #256,D6
MOVE.B (A5,D6.W),D7
SUB.W D7,D3
; Diffuse error values
DiffuseOut D1,0
DiffuseOut D2,2
DiffuseOut D3,4
; Move to next pixel
DBF D0,@1
; Clean up and exit
@4 MOVEM.L (SP)+,D3-D7/A2-A5
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
Do5BitHistogram PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE Do5BitHistogram (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; hist: Ptr;
; weight: INTEGER;
; count: INTEGER);
;
; Parameter Offsets
@rDataPtr EQU 24
@gDataPtr EQU 20
@bDataPtr EQU 16
@hist EQU 12
@weight EQU 10
@count EQU 8
; Size of parameters
@params EQU 20
; Save registers
LINK A6,#0
MOVEM.L D3-D4/A2-A3,-(SP)
; Unload parameters
MOVE.L @rDataPtr(A6),A0
MOVE.L @gDataPtr(A6),A1
MOVE.L @bDataPtr(A6),A2
MOVE.L @hist(A6),A3
MOVE.W @weight(A6),D4
EXT.L D4
MOVE.W @count(A6),D0
SUB.W #1,D0
; Compute histogram
MOVE.B #$F8,D3
@1 CLR.L D1
MOVE.B (A0)+,D1
AND.B D3,D1
LSR.W #1,D1
CLR.L D2
MOVE.B (A1)+,D2
AND.B D3,D2
LSL.W #4,D2
ADD.W D2,D1
CLR.L D2
MOVE.B (A2)+,D2
AND.B D3,D2
SWAP D2
LSR.L #7,D2
ADD.L D2,D1
ADD.L D4,(A3,D1.L)
DBF D0,@1
; Clean up and exit
MOVEM.L (SP)+,D3-D4/A2-A3
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
DoProjectHist PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DoProjectHist (minR: INTEGER;
; maxR: INTEGER;
; minG: INTEGER;
; maxG: INTEGER;
; minB: INTEGER;
; maxB: INTEGER;
; projectR: Ptr;
; projectG: Ptr;
; projectB: Ptr;
; hist: Ptr);
;
; Parameter Offsets
@minR EQU 34
@maxR EQU 32
@minG EQU 30
@maxG EQU 28
@minB EQU 26
@maxB EQU 24
@projectR EQU 20
@projectG EQU 16
@projectB EQU 12
@hist EQU 8
; Size of parameters
@params EQU 28
; Save registers
LINK A6,#0
MOVEM.L D3-D6/A2-A5,-(SP)
; Adjust minR to zero
MOVE.W @minR(A6),D0
SUB.W D0,@maxR(A6)
EXT.L D0
LSL.W #2,D0
ADD.L D0,@projectR(A6)
ADD.L D0,@hist(A6)
; Adjust minG to zero
MOVE.W @minG(A6),D0
SUB.W D0,@maxG(A6)
EXT.L D0
LSL.W #2,D0
ADD.L D0,@projectG(A6)
LSL.W #5,D0
ADD.L D0,@hist(A6)
; Adjust minB to zero
MOVE.W @minB(A6),D0
SUB.W D0,@maxB(A6)
EXT.L D0
LSL.W #2,D0
ADD.L D0,@projectB(A6)
SWAP D0
LSR.L #6,D0
ADD.L D0,@hist(A6)
; Unload addresses
MOVE.L @hist(A6),A0
MOVE.L @projectR(A6),A1
MOVE.L @projectG(A6),A2
MOVE.L @projectB(A6),A3
; Triple nested loop
CLR.L D0
CLR.L D1
CLR.L D2
MOVE.W @maxB(A6),D2
@1 MOVE.L D2,D5
LSL.W #2,D5
MOVE.L A0,A4
MOVE.L D5,D6
SWAP D6
LSR.L #6,D6
ADD.L D6,A4
MOVE.W @maxG(A6),D1
@2 MOVE.L D1,D4
LSL.W #2,D4
MOVE.L A4,A5
MOVE.L D4,D6
LSL.W #5,D6
ADD.L D6,A5
MOVE.W @maxR(A6),D0
@3 MOVE.L D0,D3
LSL.W #2,D3
MOVE.L (A5,D3.W),D6
ADD.L D6,(A1,D3.W)
ADD.L D6,(A2,D4.W)
ADD.L D6,(A3,D5.W)
DBF D0,@3
DBF D1,@2
DBF D2,@1
; Clean up and exit
MOVEM.L (SP)+,D3-D6/A2-A5
UNLK A6
MOVE.L (SP)+,A0
ADD.W #@params,SP
JMP (A0)
; **********************************************************************
SEG 'ADoConvert'
DitherRGB PROC EXPORT
; Calling sequence (Pascal conventions):
;
; PROCEDURE DitherRGB (rDataPtr: Ptr;
; gDataPtr: Ptr;
; bDataPtr: Ptr;
; row: INTEGER;
; numCols: INTEGER;
; outDataPtr: Ptr;
; ditherSize: INTEGER;
; noiseTable: TNoiseTable;
; thresTable: TThresTable;
; colorTable: Ptr;
; VAR colors: INTEGER);
;
; Parameter Offsets
@rDataPtr EQU 42
@gDataPtr EQU 38
@bDataPtr EQU 34
@row EQU 32
@numCols EQU 30
@outDataPtr EQU 26
@ditherSize EQU 24
@noiseTable EQU 20
@thresTable EQU 16
@colorTable EQU 12
@colors EQU 8
; Size of parameters
@params EQU 38
; Save registers
LINK A6,#0
MOVEM.L D3-D7/A2-A5,-(SP)
; A0-A2 are pointers to input data
MOVE.L @rDataPtr(A6),A0
MOVE.L @gDataPtr(A6),A1
MOVE.L @bDataPtr(A6),A2
; D3 will hold output pointer
MOVE.L @outDataPtr(A6),D3
; A3 is pointer to row in noise table
MOVE.L @noiseTable(A6),A3
MOVE.W @row(A6),D0
EXT.L D0
DIVU.W @ditherSize(A6),D0
SWAP D0
LSL.W #4,D0
ADD.W D0,A3
; A4 is pointer to threshold table
MOVE.L @thresTable(A6),A4
; A5 is pointer to color table
MOVE.L @colorTable(A6),A5
; D0 is dither table size
MOVE.W @ditherSize(A6),D0
; D1 is noise table index
CLR.W D1
; Loop through columns
MOVE.W @numCols(A6),D2
SUB.W #1,D2
; Save A6, use for output pointer
MOVE.L A6,-(SP)
MOVE.L D3,A6
; Compute noise value
@4 CLR.W D4
MOVE.B (A3,D1.W),D4
ADD.W #1,D1
CMP.W D0,D1
BNE.S @5
CLR.W D1
; Compute index value
@5 CLR.W D5
MOVE.B (A0)+,D5
ADD.W D4,D5
CLR.W D7
MOVE.B (A4,D5.W),D7
CLR.W D5
MOVE.B (A1)+,D5
ADD.W D4,D5
CLR.W D6
MOVE.B (A4,D5.W),D6
LSL.W #5,D6
ADD.W D6,D7
CLR.W D5
MOVE.B (A2)+,D5
ADD.W D4,D5
CLR.W D6
MOVE.B (A4,D5.W),D6
ROR.W #6,D6
ADD.W D6,D7
; See of outputing data
TST.L D3
BEQ.S @6