ffmpeg - detect frames that have a given image/logo
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I'm trying to split a video by detecting the presence of a marker (an image) in the frames. I've gone over the documentation and I see removelogo but not detectlogo ;) 

Does anyone know how this could be achieved? I know what the logo is and the region it will be on.

I'm thinking i can extract all frames to png's and then analyse them one by one (or n by n) but it might be a lengthy process..

Any pointers?

Thanks :)