Sample 22 - Replacing colors and creating transparency The sample shows how to load JPEG image from file, convert it to Palette image and change colors of all pixels where red value is less than 72 to black transparent color
> Threshold.vbs
>     Dim im
>     Set im = CreateObject("ActiveImage.Images.1")
>     'im.CreateImagePalette 300,400
>     im.SetImageType 1
>     im.ReadFromFile "C:\AI\rose.jpg"

>     im.ConvertToPaletteNoAlpha

>     width = im.GetWidth
>     height = im.GetHeight

>     colorbk_r = 0
>     colorbk_g = 0
>     colorbk_b = 0

>     Threshold  = 72

>     For x = 0  to width
>      for y = 0 to height

>       r = im.GetPixelRed(x,y)
>       g = im.GetPixelGreen(x,y)
>       b = im.GetPixelBlue(x,y)
>       if r < Threshold  then
>         im.SetColor colorbk_r, colorbk_g, colorbk_b
>         im.SetPixel x,y
>       end if
>      next
>     next

>     im.SetColor colorbk_r, colorbk_g, colorbk_b
>     im.SetTransparent 1
>     im.SetSaveAlpha 0

>     im.SetImageType 3
>     im.WriteToFile "C:\AI\Threshold.gif"
>     im.SetImageType 0
>     im.WriteToFile "C:\AI\Threshold.png"

>     im.DestroyImage
>     Set im = Nothing
> Picture 1. rose.jpg (size - 6,3Kb) | Picture 1. Threshold.gif (size - 11,4Kb)
If you have any questions or bug reports, write to active.image@tonec.com for technical support.
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