I have imported a bunch of mp4's for my daughter on my iphone (my little pony episodes). They don't show any artwork on the iPhone. The mp4's do show artwork on Windows. Is there an easy way to use the artwork that I see in Windows on the iPhone? I've done the obvious but tedious step of taking a capture of the image in Windows Explorer, saving it, and using iTunes to set the image as artwork. It works, but way too slow. I've also tried to play an mp4 in itunes and use "Set as poster frame"; that did not work. Ideally iTunes would just use the same artwork I see in Windows, but failing that, is there a Windows tool that would batch export the artwork, then I could manually set the artwork for each file in iTunes (at least saving me the step of taking a screen capture).
Why are you taking a screen capture rather than setting the artwork using the original jpg/png files? There are many metadata editors and scripts that will set the artwork so iTunes sees it on a Mac; have you tried a metadata editor for Windows to determine if iTunes will read the changes as imbedded?