On Tue, 8 Jun 2004, dreadnought wrote:
> I've been using the technique mentioned in the email below to try to get
> images with white backgrounds transparent .. I've had some good luck, but
> also some bad. Today I used the process on two .jpg's and the *entire*
> images ended up transparent. In one of the images, the foreground color is
> actually black. I've got the color picker on white and then do a color to
> alpha on white. The entire image (including the black stuff in the middle)
> gets the alternating boxes indicative of transparency.
I tried this on the image from the link you gave, wich looked at a black
case on wheels, and the color to alpha filter did as you said. The image
turned semi-transparent too.
You could add an alpha channel to the jpeg image then add a layer mask
to the image. Select the white background with the select by color tool.
Select the layer mask in the layer dialog by clicking on the layer mask
and fill the selection with black. You'll need to do this several times
by adjusting the threshold of the select by color tool until you get
want you want.
Hopes that help,
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