Interesting discussion, but not 100% clear to me yet...
I am about to buy a Synology NAS and probably an ATV3. Can I stream any videoformat (i.e. including MKV) to the ATV3? I don't mind using my Iphone as in ' intermediate' device, but I want to video to be fullscreen on my TV.
Does anybody know if that works or not?
This does not work through the current Synology system "as-is". You can, however, download the PLEX app for your Synology and air-play them this way through your iPhone. You can also do it with a few other programs going through your iMac or other devices.
There are a couple stipulations, however. In order for you to be able to stream any mkv file or the like to the Apple TV, it needs to be transcoded. This is literally the exact same thing that Handbrake and other programs do, except that it does it real time as the movie is playing (and doesn't physically change the file). This takes a lot of processor power, and therefore is not supported on ARM based NAS units (for Synology, this means models ending in j. EX: DS413j).
The other stipulation is that you must have an intermediate device, whether that is an iOS device, Mac, PC, or something else (jailbroken ATV works as well of course, but only ATV2).