How to cover sprocket holes in 8mm film?
 

I have some old 8mm film home movies which were recently digitized, and I now have them in ProRes 4444 format. They were overscanned on purpose (screenshot of a frame attached) so I know I have some cropping to do.

In addition to cropping, I'd really like to try and "cover up" the white sprocket holes with black so they are less distracting. (Is "mask" the appropriate term here?) Is this something I could do with AviSynth? If so, what function/plugin should I attempt this with? Or is there another application I would be better off using?

I realize I could just crop out the sprocket holes entirely, but if there's a reasonable way I could keep that extra portion of the image I'd really like to try.

Reviving old thread. It is possible there will be new Ai models that can use inpainting or AI scene expansion by using data from adjacent frames or generating it by the existing content. I am actively looking for this type of solution and believe it will be available soon. The clunky version is creating tiff files of each frame, using photoshop on each frame and it's inpainting tool then reassembling the frames into a video using your favorite NLE. Lets have some ideas maybe we can find a solution with the all the new Ai tools.

In theory, it might work to use some luma masking for what should be inpainted and then apply something like proPainter.
Got a sample of such a source to play around?

Depending on your available tools and their capability here is one approach based on using a NLE.

1. Place the video on the top (most visible) track. Mask the sprocket hole areas and make that portion transparent (to allow video underneath to show). The sprocket holes have some light spill over.

2. Place a copy of the video on a under track and scale/stretch is so the sprocket holes are out of the frame and add blur to taste. For the sample a 150% vertical stretch and a bit of horizontal stretch should work.

3. The attached image shows a quick and dirty sample prepared in Photoshop. By careful selection of the masked areas, and judicious used of blur and other filters you can blend the borders and make it less intrusive for most typical live video such as the parade. I did not try to do more blending to better show the areas involved. (In Photoshop I used MagicEraser because it was quick, and and then put to put the stretched video on a different layer..)

You could try luma keying but be careful to limit it to the sprocket areas.