Streaming Video Content/Conversion - MacBook Pro (iTunes) to Apple TV [.MKV to .M4V] I have a few .MKV video files that I would like to be able to list in iTunes so that I can stream to my Apple TV device. I currently use the Beamer app (MacBook) to stream them across however I was hoping that I could create a nice looking library of videos in iTunes and stream them that way instead. 

I do not need these videos to be able to play on any iOS devices, so is there any way that they can be converted to .M4V/.MP4 without loss of picture or sound quality?

I've tried few apps such as Subler - I can seem to keep picture quality however the audio is definitely poorer. My videos tend to be 1080p HD with DTS. 

Could anyone prehaps offer any solutions for full quality video streaming in iTunes?

Many thanks!
Dan.
MKV and MP4 are not video format, they are containers. An MKV can contain any type of video/audio stream.

Most of the time, MKV contains H264/AC3 DTS (video/audio; the most common format in blu-ray).

The official specification of MP4 do not allow the AC3 format for the audio channel, but the H264 format is possible for the video. Thus, you can convert losslessly an MKV to an MP4, for the video channel only. The audio channel will have to be re-encoded

I recommend using ffmpeg (a command-line tool) to achieve this goal.

Note: You can try and create an MP4 containing AC3, but I don't think it will work in iTunes or the Apple TV, even though players like MPlayerX or VLC will be able to play them.