I'm still thinking out some of the issues for my own potential SMT for my social network. One thing I am quite clear about though is that I don't know of a better way to handle the issue of copyright than by using media fingerprinting as Youtube and others do. When I looked into this for another project a few year ago, I found it was necessary to pay for access to fingerprinting databases and technology since the cost of developing a custom solution would be prohibitive vs. paying for a license.
I appreciate that for many, the idea of copyright policing is counter to anarchistic principles - but I don't really see how the network can be protected from litigation without it. I wrote about this in some detail with regards to steem, not so long ago.
Indeed, one will probably in the future need proof of creation to show that you in fact produced this first. I haven't looked into it myself, but open timestamps might be of inspiration/use.
there may be a way to make that work, yes - provided compression and recompression of files does not corrupt the mechanism.. thanks for the link. :)