Hi Vitaly,

Great work! Unfortunately, the code will throw errors in Version 12.2 when executing the finalFrames = ... cell:

ImageAdd::bdchan : The number of channels must be equal or one of them must be a single-channel image and the other a multichannel image.

It looks like the slots have to be swapped as the error will not arise for the following code:

finalFrames = Parallelize @ MapThread[
    ImageAdd[ SetAlphaChannel[ #2, 1 ], #1 ]&,
    { treeFrames, snowFrames }
];

Unfortunately, the result then is not as neat as the one you have posted here (i.e. the tree will flicker and the animation does is not looking as smooth). Since image processing is not my sweet spot, maybe you can have a quick look and fix your beautiful example? It's simply too nice to not work out.

Thanks, Guido

This post has been updated.