ThunderSoft Blu-ray Ripper copies the audio & video on a Blu-ray disc to a MKV or .mp4 file *container* -- the actual audio & video files are unaltered.
Why Blu-ray? While there is a hardware cost, with Blu-ray burners for a PC usually running in the $50-$60 range, plus the cost of a Blu-ray player, or some other device to play the video on your TV, the video is higher quality than you'll get streaming, including streaming 4k. And while Blu-ray doesn't need a fast [or any] internet connection, required for streaming, you do have to store the files somewhere. The Blu-ray movies on disc that you buy can be ruined by an almost invisible scratch, while the discs you burn have questionable longevity, plus lack a hard layer for protection, but those optical discs *may* be the cheapest, easiest storage option for many. The bigger problem with Blu-ray however, is the DRM. It's constantly changing, and prone in my experience to cause playback problems, even with a more expensive Sony Blu-ray player. And I've found that reading from discs, including the originals, doesn't work as well as reading the same files from a fast USB 3.0 stick for some reason -- the discs are prone to occasional, very brief pauses during playback using a few players/drives.
By this point, if you're still interested [ ;) ], I'd suggest getting & installing the ThunderSoft Blu-ray Ripper, but unless you buy a license, only as backup... installing it has minimal system impact, and handling the ever evolving Blu-ray DRM is always uncertain, so it's something to try if/when your normal tool(s) don't work, and sooner or later, they will not. When a new movie comes out on Blu-ray, there's a maybe 25% chance [that's just a guess] that it'll have a new type of DRM, and it'll take anywhere from a few days to weeks before your software tools are updated to handle it. The odds are that if that happens the un-updated version of ThunderSoft Blu-ray Ripper won't work either, but ya never know, and it *may* be worth a shot. If you buy a license so you get updates it *hopefully* will always work.
That said, there are other apps that will copy the files/folders on a Blu-ray disc to your hard drive, minus the DRM, which [solely IMHO] is a better solution than having the same content in a MKV file. If having an MKV file appeals to you however, MakeMKV is free while is beta, and updated regularly. It's also been in beta forever, & may never reach the milestone to become a paid app.
Installing ThunderSoft Blu-ray Ripper means adding the program's folder, with 82 files/3 folders taking up ~103 MB, plus a folder in C:\Users\[UserName]\AppData\Roaming. The only registry keys are for uninstall & checking for updates.
From the comments section of the GOTD download page:
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If it helps...
The Rippers we've seen on GOTD all reencode the video on a DVD, or more rarely a Blu-ray disc, while the copy apps do just that, copy the files to a hard drive after dealing with [removing] DRM. ThunderSoft Blu-ray Ripper is more along the lines of the MakeMKV app [free while in beta, which seems to be always], copying the contents on a Blu-ray disc, but instead of storing those files in the same folder structure as on the Blu-ray disc, puts them in an MKV container. That way you don't need a specialized player that understands the Blu-ray folder structure & files. And when Thundersoft calls it lossless MKV, they mean that the Blu-ray content is not reencoded -- not that the MKV itself is lossless, because the content on the Blu-ray itself is not lossless... the original lossless 1080p video would take up several hundred GB. One benefit of putting the Blu-ray video into an MKV file is that you only have one file -- the video can be split into many .m2ts files on a Blu-ray as part of the DRM [the free tsMuxeR app will copy a Blu-ray video without DRM, merging those separate .m2ts files into one large file].
Because ThunderSoft Blu-ray Ripper does not reencode the video, you're probably looking at [very] roughly 1/2 an hour to get the new MKV file written on your hard drive, and you're looking at 20 - 50 GB -- it varies depending on the video bit rate, and thus the size of the files on the Blu-ray. Whether it's better to have the video in a MKV file rather than an original .m2ts file is up to you -- IMHO more players understand .m2ts than MKV, but could be wrong. Do note that not every player that works with MKV will play the subtitles or understand the chapters, and the same can be said for players that work with .m2ts. I've found that VLC, including mobile versions, does work with subs & chapters in a regular Blu-ray folder layout. The free SubtitleEdit can OCR subs to an .srt file that can be displayed in more players.
As noted in the ad copy, the audio & video on a Blu-ray disc can be edited &/or re-encoded. It doesn't take long if you're reducing the frame size to DVD dimensions, but 1080p at a reduced bit rate to cut down the file size does take a long time, & even 720p is not quick. AVC/H.264 [or H.265] encoding is CPU intensive, unless you use a GPU encoder, which will reduce quality, though mpg2 encoding is a Much less demanding, included in the Blu-ray specs, and while not as efficient at storing the video, can still look quite good. More importantly, it won't take nearly as long on a lower powered PC/laptop.