I think you can make your Blu-ray Disc or BDMV folder into MKV file.
I choose MKV form as my lossless bluray backup. Cause MKV is a container file format in which there can be many audio, video and subtitles streams, allowing the user to store a complete movie in a single file.
Recently I start to use a tool *** to backup my blu rays to mkv files and store them in my 2TB hard disk .Very exciting, Playing the MKV files is flawless and i can get a high definiton enjoyment on my WD TV live Plus, ,moreover i can easily change audios and subs, skip chapters just as directly playing blu-ray Disc on my PC.
A Detailed Blu ray backup:
1.
Store unprotected Blu-ray Discs on your hard drive.
To copy movie from a copy-protected Blu-ray disc to your hard drive, you’ll need a Blu-ray decrypting tool that can handle AACS and BD+ protections.
AnyDVD HD is the best program for removing copy-protection from BD discs.
Pros: You can make a 1:1 physical Blu-ray copy and play it in Blu-ray players and PS3.
2.
Copy/Burn Blu-ray Disc to ISO
First, copy a movie from a copy-protected Blu-ray disc to your hard drive. Then just create an ISO image from it using software like freeware
ImgBurn or shareware
Nero.
Pros: You can make a 1:1 physical Blu-ray copy and play it in Blu-ray players and PS3.
3.
Copy/Burn Blu-ray Disc to a blank BD-R 25GB/50GB . To copy movie from a copy-protected Blu-ray disc, you’ll need a Blu-ray decrypting tool that can handle AACS and BD+ protections.
AnyDVD HD is the best program for removing copy-protection from BD discs.
Pros: You can make a 1:1 physical Blu-ray copy and play it in Blu-ray players and PS3.
Cons: You may face more complicated situation when copying a 30GB movie--- you have to either compress the BD contents to fit for a 25GB single layer Blu-ray Disc(which is time-consuming), or copy it to a 50GB dual layer Blu-ray Disc which is much more expensive.
4.
Copy Blu-ray main movie to MKV stripping out the rest of the Blu Ray disc content
Generated MKV video includes main movie only, without Blu-ray movie menu or any add-ons.
There are plenty of such tools promoted by spam, so there is a high chance that you will get a low quality software.