Which Audio Track Should I Keep?

[mpalm887]

Just been happily ripping my Blu-ray collection with BD Rebuilder. Most of the films I've done so far are either chick-flick's (Hitch, Hairspray, Mama Mia etc.) or kids movies. I've encoded the audio to AC3 (or left it as such if it was the original track) but now that I'm getting to some more epic films like the Dark Knight, Superman Returns etc, I want to make sure I keep as close to original audio as possible.

If there were HD tracks I'd be keeping them but most of these Blu's are in uncompressed PCM. If I try to keep these raw soundtracks am I going to be looking at massive file sizes? I've been compressing 30GB .m2ts files down to about 12GB so far (I don't know how much of the .m2ts is audio when you've got an uncompressed soundtrack as well as a DD 5.1).

Reason I ask is because I don't want to give it a target file size and find that the video had to be super-compressed because I chose to keep the uncompressed audio in tact and it's taking too much of the target size up.

Of course I could do some tests but BD Rebuilder doesn't exactly work quickly if you know what I mean. It'd be 48 hours before I'd get any answers.

BTW: I guess BD Rebuilder doesn't support DTS-HD or True-HD, which I wish I could have. If I do have Blu's that have these tracks and I want to keep them what's the tool to use to keep that track but still encode video with x264? Will RipBot do it?

[redwudz]

Not many encoders support True-HD audio. I use DTS audio for my BD>MKV conversions. I size them for a DVD-9 and use two passes with RipBot.

A typical MKV 1:42 long and 7.94GB has 6.85GB MKV video and 1.08GB DTS audio file sizes.
(I ran this one through tsMuxeR and demuxed it to separate files to check the sizes of the audio and video files.)

[mpalm887]

Thanks for the reply. Are there ANY encoders out there that DO support the HD audio formats?

Also, are you saying you use DTS on your MKV conversions if it's an available track? or are you saying you encode the uncompressed PCM to DTS? And, if this is the case...um...how do you do that?

Lastly, if I use MakeMKV can I preserve the HD audio? It doesn't do any encoding right so I would think so. I'm ripping my copy of Quantum of Solace right now and it's got a DTS-HD track on it and that's the only one I kept. But it shows up in the interface as "DTS 3/2 + 1 English."

The problem I'll face is when I try to feed it into another x264 front end like handbrake or RipBot to shrink the MKV down a little.