Help with pixelated smoke layer on gif

[alexwook]

Hi,

I learnt how to overlay a GIF effect on a static image from this excellent forum, it works perfectly with small objects like snow or rain, although when I try to add smoke or light effects, it becomes pixelated and the colour gradient is too noticeable - see below. I am using gimp 2.10

https://gifyu.com/image/Spdw4




(this isnt my best effort but it illustrates what I mean)

I have tried using higher definition GIFs and reducing the size of the image but nothing seems to help.

Does anyone have any ideas or advice that I could try please? I'm not sure if my source is not good enough, or my knowledge!

Alex

[rich2005]

It is the 256 color limitation of the indexed gif format. The index colors are held in a colormap and might be ok as individual images each with their own colormap but when combined by Gimp as an animation only one colormap is used.

There is one old utility gifsicle - (there is a Windows version somewhere) which will keep each individual colormap per image.

Totally failed to make a good small demo to show but as an example gifsicle tells me this
[gifsicle: warning: too many colors, using local colormaps (You may want to try ‘--colors 256’.)

..and it is that reduction to 256 colors that Gimp forces on your animation. Of course if you get your gifsicle animation, never open it in Gimp, which then imposes a single colormap. Another try at a small animation. It is a gif, open in Gimp it is in RGB mode, convert to indexed and colors are reduced.

   

Edit: ...before the others jump in, there is of course the .webp format for animations which uses RGB and thousands of colours. Not all sites / browsers support this format.

[alexwook]

thank you