Image convolution: Difference between revisions

=={{header|Action!}}==

{{libheader|Action! Bitmap tools}}

<lang Action!>INCLUDE "H6:LOADPPM5.ACT"

DEFINE HISTSIZE="256"

PROC PutBigPixel(INT x,y BYTE col)

IF x>=0 AND x<=79 AND y>=0 AND y<=47 THEN

y==LSH 2

col==RSH 4

IF col<0 THEN col=0

ELSEIF col>15 THEN col=15 FI

Color=col

Plot(x,y)

DrawTo(x,y+3)

FI

RETURN

PROC DrawImage(GrayImage POINTER image INT x,y)

INT i,j

BYTE c

FOR j=0 TO image.gh-1

DO

FOR i=0 TO image.gw-1

DO

c=GetGrayPixel(image,i,j)

PutBigPixel(x+i,y+j,c)

OD

OD

RETURN

INT FUNC Clamp(INT x,min,max)

IF x<min THEN

RETURN (min)

ELSEIF x>max THEN

RETURN (max)

FI

RETURN (x)

PROC Convolution3x3(GrayImage POINTER src,dst

INT ARRAY kernel INT divisor)

INT x,y,i,j,ii,jj,index,sum

BYTE c

FOR j=0 TO src.gh-1

DO

FOR i=0 TO src.gw-1

DO

sum=0 index=0

FOR jj=-1 TO 1

DO

y=Clamp(j+jj,0,src.gh-1)

FOR ii=-1 TO 1

DO

x=Clamp(i+ii,0,src.gw-1)

c=GetGrayPixel(src,x,y)

sum==+c*kernel(index)

index==+1

OD

OD

c=Clamp(sum/divisor,0,255)

SetGrayPixel(dst,i,j,c)

OD

OD

RETURN

PROC Main()

BYTE CH=$02FC ;Internal hardware value for last key pressed

BYTE ARRAY dataIn(900),dataOut(900)

GrayImage in,out

INT ARRAY sharpenKernel=[

65535 65535 65535

65535 9 65535

65535 65535 65535]

INT size=[30],x,y,sharpenDivisor=[1]

Put(125) PutE() ;clear the screen

InitGrayImage(in,size,size,dataIn)

InitGrayImage(out,size,size,dataOut)

PrintE("Loading source image...")

LoadPPM5(in,"H6:LENA30G.PPM")

PrintE("Convolution...")

Convolution3x3(in,out,sharpenKernel,sharpenDivisor)

Graphics(9)

x=(40-size)/2

y=(48-size)/2

DrawImage(in,x,y)

DrawImage(out,x+40,y)

DO UNTIL CH#$FF OD

CH=$FF

RETURN</lang>

{{out}}

[https://gitlab.com/amarok8bit/action-rosetta-code/-/raw/master/images/Image_convolution.png Screenshot from Atari 8-bit computer]