Anonymous user
Image convolution: Difference between revisions
no edit summary
(added omit from ML/I) |
No edit summary |
||
Line 369:
'blurred.ppm' writeppm~ blur_kernel kernel_filter readppm 'original.ppm'
=={{header|Liberty BASIC}}==
In the following a 128x128 bmp file is loaded and its brightness values are read into an array.
<br>
We then convolve it with a 'sharpen' 3x3 matrix. Results are shown directly on screen.
<br>
NB Things like convolution would be best done by combining LB with ImageMagick, which is easily called from LB.
<lang lb>
dim result( 300, 300), image( 300, 300), mask( 100, 100)
w =128
h =128
nomainwin
WindowWidth = 460
WindowHeight = 210
open "Convolution" for graphics_nsb_nf as #w
#w "trapclose [quit]"
#w "down ; fill darkblue"
hw = hwnd( #w)
calldll #user32,"GetDC", hw as ulong, hdc as ulong
loadbmp "img", "alpha25.bmp"' 128x128 pixels
#w "drawbmp img 20, 20"
#w "up ; color white ; goto 292 20 ; down ; box 420 148"
#w "up ; goto 180 60 ; down ; backcolor darkblue ; color cyan"
#w "\"; "Convolved with"
for y =0 to 127 ' fill in the input matrix
for x =0 to 127
xx =x + 20
yy =y + 20
CallDLL #gdi32, "GetPixel", hdc as uLong, xx as long, yy as long, pixcol as ulong
call getRGB pixcol, b, g, r
image( x, y) =b
'#w "color "; image( x, y); " 0 "; 255 -image( x, y)
'#w "set "; x + 20; " "; y +20 +140
next x
next y
#w "flush"
print " Input matrix filled."
#w "size 8"
for y =0 to 2 ' fill in the mask matrix
for x =0 to 2
read mask
mask( x, y) =mask
if mask = ( 0 -1) then #w "color yellow" else #w "color red"
#w "set "; 8 *x +200; " "; 8 *y +80
next x
next y
data -1,-1,-1,-1,9,-1,-1,-1,-1
#w "flush"
print " Mask matrix filled."
#w "size 1"
mxx =0: mnn =0
for x =0 to 127 -2 ' since any further overlaps image edge
for y =0 to 127 -2
result( x, y) =0
for kx =0 to 2
for ky =0 to 2
result( x, y) =result( x, y) +image( x +kx, y +ky) *mask( kx, ky)
next ky
if mxx <result( x, y) then mxx =result( x, y)
if mnn >result( x, y) then mnn =result( x, y)
next kx
scan
next y
next x
range =mxx -mnn
for x =0 to 127 -2
for y =0 to 127 -2
c =int( 255 *( result( x, y) -mnn) /range)
'#w "color "; c; " "; c; " "; c
if c >128 then #w "color white" else #w "color black"
#w "set "; x +292 +1; " "; y +20 +1
scan
next y
next x
#w "flush"
wait
sub getRGB pixcol, byref r, byref g, byref b
b = int( pixcol / (256 *256))
g = int( ( pixcol - b *256 *256) / 256)
r = int( pixcol - b *256 *256 - g *256)
end sub
[quit]
close #w
CallDLL #user32, "ReleaseDC", hw as ulong, hdc as ulong
end
</lang>
Screenview is available at [[http://www.diga.me.uk/convolved.gif]]
=={{header|Mathematica}}==
| |||