I have just gone through this site.
My project involves creating a Media Library by copying media files from VCDs, etc and allowing subscribed users to download these.
So is OpenML required for my application given the following situations
1)My Media Library is only supposed to create a collection of Media Files and give a link to subscribers to download the same
2)My Media Library has an additional task of developing a media player to be used by subscribers that will play all the files in the collection