Blurry Concept (Source Included)

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dw817

(Posted 2016) [#1]

One of the more difficult things to do in graphics is to have a fast blur of a screen or page.

While it can certainly be accomplished by reading every single pixel and get the median to plot, surely there is a simpler way.

Here is my entry to convert a sharp image to a blur. My question is, can this be improved upon, and if so, what code would you use instead where the blur is centered and the edges do not bleed pixels as this one does ?

' simple and fast blur of graphics
Strict
Graphics 1024,768
SetBlend alphablend
Local img:TImage=LoadImage(LoadBank("http::cdn.akamai.steamstatic.com/steam/apps/229754/ss_e64cb5c319acb3e50cf440f716aa18ed02d08971.600x338.jpg"))
Local i,j
DrawImage img,512-ImageWidth(img)/2,384-ImageHeight(img)/2
img=CreateImage(1024,768)
GrabImage img,0,0
Flip
WaitKey
Cls
SetAlpha 1/63.0
For i=-7 To 7
  For j=-7 To 7
    DrawImage img,j,i
  Next
Next
Flip
WaitKey

TomToad

(Posted 2016) [#2]

Don't understand the need for the GrabImage, so I removed it. Used SetViewport to remove the blurred border.

' simple and fast blur of graphics
Strict
Graphics 1024,768
Local img:TImage=LoadImage(LoadBank("http::cdn.akamai.steamstatic.com/steam/apps/229754/ss_e64cb5c319acb3e50cf440f716aa18ed02d08971.600x338.jpg"))
Local i,j,x,y
x = (1024-img.Width)/2
y = (768-img.Height)/2
DrawImage img,x,y
Flip
WaitKey

Cls
SetBlend alphablend
SetAlpha 1/63.0
SetViewport (1024-img.Width)/2,(768-img.Height)/2,img.Width,img.Height

For i=-7 To 7
  For j=-7 To 7
    DrawImage img,x+j,y+i
  Next
Next
Flip
WaitKey

dw817

(Posted 2016) [#3]

Ah ! Something I didn't consider. I liked the smoothed rounded edges below, I didn't want to lose those. But by seeing your SetViewPort, that definitely fixes the problem.

Nicely done, TomToad.

I am still wondering if there is there a better coding method to create a blurred image from a sharp one ?