Some videos not showing up on AppleTV from iMac's iTunes library

Having a strange problem. Not sure if it is an iTunes problem or an AppleTV problem but I will try here first.

I have several videos in my library, some of which are digitized home videos I edited/rendered, others are AppleTV converted DVD's I own. For some reason, many of them are not showing up on my AppleTV when I go into "Computers" off the main menu and select my iMac with the iTunes library of them. Some show up, but more and more do not. They are all properly formatted and done so using Compressor settings for AppleTV. No idea why some are not showing up.

If you look on the iMac with the library on it, they all show up fine. And if I try and play the video on my iMac but tell it to use AirPlay to play the video on the AppleTV, it plays just fine on the TV/AppleTV. I do have Home Sharing turned on for ALL my media and I also use iTunes Match service.

When I try and use my iPad to access videos under the "shared" option and select my iMac's iTunes library, I get the same incomplete list. So I am thinking it's the iTunes library that's sending out an incomplete list for some reason. No idea why.

I have tried drag-and-dropping the videos into the iTunes library as well as using the "Add to library" menu command, neither makes a difference.

Any suggestions?

Thanks.