From what I've read, my understanding is that when MakeMKV or other programs (like Handbrake) find duplicate files on the media (DVD or BD), that it's the same file, but that it's listed in more than one title. From what I get this means that, for example, a menu option can specify that file to be played by itself or as one in a sequence of files. But the main point is that some files may appear under multiple titles?
Am I right about that so far? (If not, please correct me!)
I'm ripping BDs from a TV series and finding that files seem to be duplicates, but have different source files (as reported by MakeMKV). For instance, 6 episodes of the show on the DVD. I find 6 files, each varying a bit in length. (Like 5.9GB, 5.8GB, 6.1GB and so on.) Then I find a 2nd set of files that have the same lengths (and usually in the same order). But the source files are different. In some cases when I've played these files, they're the same - same run time length, no extra commentary, nothing I can find that makes them seem different.
Could they still be the same file and, if so, is there a reason they don't have the same source file name? In the case of the BD I'm looking at now, I see file 00056.mpls and file 00076.mpls is the same running time and may be the same length. (It's listed as 5.8GB, so I know that's rounded off and there could still be a difference in file length.)
It seems like all the discs in this series (and it's a LONG lasting series) have these double-file situations, so that means a LOT of extra ripping unless there's some way to verify ahead of time if the files are the same.
Duplicate Files on DVD and BD - Questions...
Re: Duplicate Files on DVD and BD - Questions...
DVDs are a little different but blu-rays and UHDs are pretty much the same.
A title on a blu-ray is like a playlist. The items in a title are called segments. In MakeMKV, after a blu-ray has been scanned and you can see all the things that can be ripped, when you highlight a title (on the left) in the 'Info' box (on the right) various details about the item are displayed. The 'Source file name' will be something like 00105.mpls. That .mpls file is the title. A few lines down there is 'Segment map' which will have 1 or more numbers in an ordered sequence. These numbers are the names of segments.
If a decrypted backup of a blu-ray is made, the segments live in the BDMV/STREAM folder as .m2ts files. The names will be something like 00022.m2ts. Those file names correspond to the numbers listed in the Segment map. In this fictional example, a title who's segment map includes segment 22 means the file 00022.m2ts is part of that title.
A segment can be part of more than one title. This is how, for example, both a director's cut and the theatrical release of a movie can be on the same blu-ray. In that case, those two titles have overlapping segment maps, with only the parts that are different between the versions of the movie being different.
This implies that in MakeMKV, if a title (of a blu-ray or UHD) is highlighted, the title (the .mpls file) and the segment map can be examined to determine if it is the same or different as some other title. Making a decrypted backup of a blu-ray can make it easy to access the individual segments. VLC, for instance, can play those .m2ts files. This can make it easier to understand a disc that has been authored in a confusing way.
A title on a blu-ray is like a playlist. The items in a title are called segments. In MakeMKV, after a blu-ray has been scanned and you can see all the things that can be ripped, when you highlight a title (on the left) in the 'Info' box (on the right) various details about the item are displayed. The 'Source file name' will be something like 00105.mpls. That .mpls file is the title. A few lines down there is 'Segment map' which will have 1 or more numbers in an ordered sequence. These numbers are the names of segments.
If a decrypted backup of a blu-ray is made, the segments live in the BDMV/STREAM folder as .m2ts files. The names will be something like 00022.m2ts. Those file names correspond to the numbers listed in the Segment map. In this fictional example, a title who's segment map includes segment 22 means the file 00022.m2ts is part of that title.
A segment can be part of more than one title. This is how, for example, both a director's cut and the theatrical release of a movie can be on the same blu-ray. In that case, those two titles have overlapping segment maps, with only the parts that are different between the versions of the movie being different.
This implies that in MakeMKV, if a title (of a blu-ray or UHD) is highlighted, the title (the .mpls file) and the segment map can be examined to determine if it is the same or different as some other title. Making a decrypted backup of a blu-ray can make it easy to access the individual segments. VLC, for instance, can play those .m2ts files. This can make it easier to understand a disc that has been authored in a confusing way.
Re: Duplicate Files on DVD and BD - Questions...
Thank you!
At first I wondered about the Segment map, then I realized that the discs from the TV show I'm currently ripping have episodes that are just 1 segment long.
I have two screenshots of one of the BDs I'm trying to rip with this one series. I know it's 6 episodes per disc. When I've played files from previous discs in the series (after ripping them), I find, in a case like this, I get 2 copies of each episode. Most of the time the two copies are identical, but other times one has commentary on it. In both shots I've selected one of the two files 5.7GB in size. Is the 15 in the segment map in both screen shots the number of a particular segment on the disc? In other words, with both titles being one segment long, and the number in the map being the same, does that mean both titles are using only segment 15?
At first I wondered about the Segment map, then I realized that the discs from the TV show I'm currently ripping have episodes that are just 1 segment long.
I have two screenshots of one of the BDs I'm trying to rip with this one series. I know it's 6 episodes per disc. When I've played files from previous discs in the series (after ripping them), I find, in a case like this, I get 2 copies of each episode. Most of the time the two copies are identical, but other times one has commentary on it. In both shots I've selected one of the two files 5.7GB in size. Is the 15 in the segment map in both screen shots the number of a particular segment on the disc? In other words, with both titles being one segment long, and the number in the map being the same, does that mean both titles are using only segment 15?
- Screen Shot 2022-03-12 at 12.18.50 PM.png (229.47 KiB) Viewed 4499 times
- Screen Shot 2022-03-12 at 12.18.30 PM.png (228.98 KiB) Viewed 4499 times
Re: Duplicate Files on DVD and BD - Questions...
Yes. Two different titles (00073.mpls & 00053.mpls) but each title only has the same segment. There are things besides just the list of segments that can be declared in a title. I most often see two titles with the same segment map in cases where one title has a whole bunch of languages (both audio tracks and subtitles) and the other title has only English and Japanese. If you look at the underlying segments, the .m2ts files, you'll find all the audio tracks and subtitles are there.
Re: Duplicate Files on DVD and BD - Questions...
Okay - got it now!
Thank you.
Thank you.