How can I remove the background from a gif?

[bobhwantstoknow]

Hello,

I have a gif with a stable static background image and movement in the foreground. Is there an easy way to mask out the movement and remove the background? For example, if I wanted to create my own Travolta gif http://imgur.com/j51uHm1 , or BB8 https://media.giphy.com/media/eEbiAqk9YUT5e/giphy.gif

[fmw42]

Are these the images you want to remove the background or the result of removing the background. If the former, namely a reasonably constant color background, then just use

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convert image -fuzz XX% -transparent yourbackgroundcolor result

or

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convert image -fuzz XX% -fill none -draw "alpha 0,0 floodfill" result

for each frame. The result will have a transparent background

Please always provide your IM version and platform when asking questions, since the syntax may differ.

[fmw42]

If it is an animated gif and you want all the frames with tranparent background, then

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convert -delay Y animation.gif -coalesce -fuzz XX% -transparent yourbackgroundcolor -loop X -layers optimize new_animation.gif

[bobhwantstoknow]

Those are examples of the types of results I would like to achieve by removing the backgrounds from the original videos/gifs.

Version: ImageMagick 6.8.9-9 Q16 i586 2016-02-05

[fmw42]

Background removal of non-constant background is very difficult. There is no good way that I know besides manually tracing the boundary. There are some tools out there that make it easier, but one still has to outline roughly. See for example:

https://clippingmagic.com/
http://research.microsoft.com/pubs/1474 ... rabcut.pdf
https://graphics.ethz.ch/teaching/forme ... apping.pdf
http://docs.opencv.org/3.1.0/d8/d83/tut ... #gsc.tab=0

[bobhwantstoknow]

I was afraid that might be the case. Thanks for the clippingmagic suggestion.

[fmw42]

I posted a few other links, one is from OpenCV for grabcut.

[snibgo]

If the background doesn't change between frames, you can use that to find it.

[fmw42]

Adding to what snibgo said, I think he is referring to frame-to-frame differences to see what is changing and what is not, if the background does not change between frames.

By tacking on, you run the risk of the IM developers not seeing your specific question. Yes, all questions are about this vulnerability, but each system and IM version may be different, in general, and need different responses. There have been many questions, each asking a different aspect of the vulnerability.That is why I suggested new topics for each.

[appy]

This seems to do part of the trick but each previous frame is overlayed:
convert bg-yellowish.gif -fuzz 3% -transparent "#fff5ba" a1.gif

I grabbed the yellowish gif from here:
https://static.ezgif.com/images/bg-yellowish.gif

I am able to do what I need at ezgif.com with the "don't stack frames" option, but I need to do this in code.

[fmw42]

Try this:

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convert -dispose background bg-yellowish.gif -coalesce -fuzz 3% -transparent "#fff5ba" -layers optimize a1.gif