Legacy ImageMagick Discussions Archive

So, I have an original image and a modified version of the same image with a transparent foreground. Both images (including the foreground in the modified image) seem to have transparency. What I want to do is remove the original image portion from the modified image so I get the transparent foreground by itself with no traces of the original image. What command should I use to achieve this?

ImageMagick Version: ImageMagick 6.9.3-4 Q16 x64 2016-02-13 (Running on Windows 10)

I don't understand. If you remove the original image apart from the transparent foreground, what are you left with? Example images might help.

Please also read the IMPORTANT: Please Read This FIRST Before Posting thread.

snibgo wrote:I don't understand. If you remove the original image apart from the transparent foreground, what are you left with? Example images might help.

Please also read the IMPORTANT: Please Read This FIRST Before Posting thread.

Basically, you remove the original image from the modified image and you're left with the transparent foreground.

How about:

snibgo wrote:How about:

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convert in.png -alpha transparent out.png

That did not work, it just made the entire image transparent.

Plus, I am trying to remove a known background of an image that has a transparent foreground.

If you just want the alpha channel of the image (transparency) use

fmw42 wrote:If you just want the alpha channel of the image (transparency) use

Code: Select all

convert image.png -alpha extractf alphachannel.png

Actually, what I'm trying to do is remove a known background from an image, although the foreground is transparent.

If you remove the background channels, all you are left with is the alpha channel.

If you want the background area of the image to be removed in the sense of making it black (or white or some other color), leaving the opaque foreground and transparency still where the background exists, then use