Question about decryption of .m2ts files

[mwalimu]

First off, my understanding is that when ripping a Blu-ray disk, the .m2ts files must be decrypted, whereas everything else in the BDMV folder structure can simply be copied. (If that's wrong, please educate me.)

In other contexts, decryption is an algorithmically exact process: either it works and you get a decrypted file, or it doesn't and you get an error message or binary garbage. My question: Is that also true of decrypting .m2ts files when ripping a Blu-ray disc?

Let me put it another way. There are multiple software applications that can be used to rip Blu-rays - AnyDVD, MakeMKV backup, DVDFab to name three. Do any of these, as a part of their functionality to copy a BD to the user's harddrive, use any sort of video encoding/decoding or other processing of the video content that could produce output that differs in the slightest from the others (while still being playable in applications such as VLC)?

[netmask56]

MakeMKV just wraps the main movie or whatever you select in a MKV container - doesn't re-encode so basically size in = size out same for quality quality in = quality out. DVDFab does decode and re-encode to whatever format the user has selected, so there could be a reduction in size, if that's what you want but the quality will change. AnyDVD is probably the same but I haven't used it so don't know. I use MakeMKV for the main movie as I'm not remotely interested in 'extras'. Transferred my entire disc collection to my NAS.

[mwalimu]

Just to clarify... For the purposes of my question, I wanted to strictly limit the comparison to the .m2ts files created by MakeMKV backup to copy a Blu-ray disk, and DVDFab HD Decrypter. I realize both MakeMKV and DVDFab both have a lot more functionality beyond that.

[netmask56]

I really don't understand what you are getting at. The MKV file produced by MakeMKV using your .m2ts file is identical to the original .m2ts on the disc as far as resolution, quality and size. What parameter is there to compare? Process it through DVBFab and that's a different story, depends on the parameters YOU choose in that program. All I can suggest is do what I do, experiment and make my own judgement. MakeMKV is free, the others offer trial periods. Good luck maybe someone else can expand on your query.

[lingyi]

Set your mind that a RIP (despite how many misuse the term) is one thing only, an EXACT BIT FOR BIT COPY (less the copy protection) of the video files. As netmask56 stated, MakeMKV rips and remuxes the video files into an .mkv container. It's like transferring a bakery cake from the box to a home cake holder. The cake is exactly the same, but in a different container. If you choose any extras, they are placed into individual .mkv containers and the menu structure is lost. This would be akin to buying a a dozen cupcakes from the bakery and placing them into individual boxes. Same cupcake, different container.

In order to recreate the file/folder structure of files that have been remuxed into an .mkv container, you would have to remux them back into .m2ts and recreate the file/folder structure of the original disc.

MakeMKV does allow backup of the entire Blu-Ray/Video DVD files/folders structure to the hard drive, but this is rarely used since it requires a media player that can (most can't) correctly navigate the complex Blu-Ray menu structure.

MakeMKV does not allow the ripping to .iso which is an exact copy of the Blu-Ray/Video DVD files/folder structure in an .iso container on your hard drive. In this case, taking a bakery cake in the box and putting it into another box. A Blu-Ray .iso isn't really practical since almost no media player can play it due to Blu-Ray licensing requirements.

DVDFab HD Decrypter (and other RIP programs) allows ripping and remuxing into .mkv and .mp4 containers, as well as ripping to an .iso which can be used to burn a copy of the disc to a new Blu-Ray or Video DVD. Since burning programs like ImgBurn can easily take a non-.iso backup (i.e. files/folders) and correctly create the necessary structure for burning, this is another reason why ripping a Blu-Ray to .iso is generally useless.

The other function of most ripping programs is the encoding (actually reencoding) of the rip to another, usually smaller and lossy format that can be placed into various containers such as .mkv and .mp4.

To reiterate, despite what others (including the program makers) say, you cannot rip (i.e. create an exact bit for bit copy of the video files) to anything except files/folders or .iso. Anything else is ripping and remuxing or ripping and encoding (with quality loss).

[lingyi]

Let me put it another way. There are multiple software applications that can be used to rip Blu-rays - AnyDVD, MakeMKV backup, DVDFab to name three. Do any of these, as a part of their functionality to copy a BD to the user's harddrive, use any sort of video encoding/decoding or other processing of the video content that could produce output that differs in the slightest from the others (while still being playable in applications such as VLC)?

To answer this question more directly, the answer is maybe.

Some programs by default rip and convert (encode) files unless you specify that they rip only. So beware.

For example, the free version of DVDFAB HD Decrypter limits your options:

"Convert DVDs/Blu-rays/Videos to MKV or MP4 Videos

While used as a free DVD & Blu-ray ripper or video converter software, HD Decrypter can rip DVDs, Blu-rays and convert non-H.265/4K videos only with MKV.Passthrough and MP4.Free conversion profiles. What's more, with the MP4.Free conversion profile, the output videos can retain at most two channels regarding audios, and 480p quality regarding videos." My bold.

[mwalimu]

Let's try this one more time... I insert a BD disc, then use MakeMKV Backup to copy the Blu-ray folder structure to my hard drive, resulting in decrypted .m2ts files in the resulting BDMV\STREAM folder. I don't do anything else with MakeMKV, just the backup. Are these .m2ts files bit-for-bit identical to the ones I would get if I copied the files from the BD disc with AnyDVD?

[jan5678]

Let's try this one more time... I insert a BD disc, then use MakeMKV Backup to copy the Blu-ray folder structure to my hard drive, resulting in decrypted .m2ts files in the resulting BDMV\STREAM folder. I don't do anything else with MakeMKV, just the backup. Are these .m2ts files bit-for-bit identical to the ones I would get if I copied the files from the BD disc with AnyDVD?

Yes it would, the source is in both cases the same, minus the copy protection

[lingyi]

Let's try this one more time... I insert a BD disc, then use MakeMKV Backup to copy the Blu-ray folder structure to my hard drive, resulting in decrypted .m2ts files in the resulting BDMV\STREAM folder. I don't do anything else with MakeMKV, just the backup. Are these .m2ts files bit-for-bit identical to the ones I would get if I copied the files from the BD disc with AnyDVD?

Yes.

Like .mkv, .mp4 and numerous others, .m2ts is a container for a Blu-Ray compliant video file.*

While the video file contained within the different containers is bit for bit exactly the same, since each container contains data for playback, file sizes are different and a CRC check will provide different hashes.

*Unlike the other other containers, .the file formats that can be contained in a .m2ts or .mts container is restricted:

"Formats

The BDAV container format used on Blu-ray Discs can contain one of the three mandatory supported video compression formats H.262/MPEG-2 Part 2, H.264/MPEG-4 AVC or SMPTE VC-1[15] and audio compression formats such as Dolby Digital, DTS or uncompressed Linear PCM. Optionally supported audio formats are Dolby Digital Plus, DTS-HD High Resolution Audio, DTS-HD Master Audio and Dolby TrueHD.[11][16]

The BDAV container format used on AVCHD equipment is more restricted and can contain only H.264/MPEG-4 AVC video compression and Dolby Digital (AC-3) audio compression or uncompressed LPCM audio.[14]"

Source: Wikipedia - https://en.wikipedia.org/wiki/.m2ts

Here's the MediaInfo text for a .m2ts and .mkv of the same movie. The video and audio info is identical with the .mkv containing additional info.

Note: Codec ID: 27 = AVC


General
ID : 0 (0x0)
Complete name :
Format : BDAV

Format/Info : Blu-ray Video
File size : 37.2 GiB
Duration : 1 h 59 min
Overall bit rate mode : Variable
Overall bit rate : 44.4 Mb/s
Maximum Overall bit rate : 48.0 Mb/s

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : 27
Duration : 1 h 59 min
Bit rate mode : Variable
Maximum bit rate : 37.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive

Audio #1
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Muxing mode : Stream extension
Codec ID : 134
Duration : 1 h 59 min
Bit rate mode : Variable
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless

Audio #2
ID : 4353 (0x1101)
Menu ID : 1 (0x1)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Muxing mode : Stream extension
Codec ID : 134
Duration : 1 h 59 min
Bit rate mode : Variable
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless

Audio #3
ID : 4354 (0x1102)
Menu ID : 1 (0x1)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Muxing mode : Stream extension
Codec ID : 134
Duration : 1 h 59 min
Bit rate mode : Variable
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless

Text #1
ID : 4608 (0x1200)
Menu ID : 1 (0x1)
Format : PGS
Codec ID : 144
Delay relative to video : 917 ms

Text #2
ID : 4609 (0x1201)
Menu ID : 1 (0x1)
Format : PGS
Codec ID : 144

General
Unique ID : 315471713390279103708045045773755602779 (0xED55A45658CC408311B8C9A22945D75B)
Complete name
Format : Matroska
Format version : Version 2
File size : 37.5 GiB
Duration : 1 h 59 min
Overall bit rate mode : Variable
Overall bit rate : 44.9 Mb/s
Movie name
Encoded date : UTC 2019-06-23 19:16:33
Writing application : MakeMKV v1.14.4 win(x64-release)
Writing library : libmakemkv v1.14.4 (1.3.5/1.4.7) win(x64-release)

Video
ID : 1
ID in the original source medium : 4113 (0x1011)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 1 h 59 min
Bit rate mode : Variable
Bit rate : 35.4 Mb/s
Maximum bit rate : 37.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.712
Stream size : 29.6 GiB (79%)
Language : English
Default : No
Forced : No
Original source medium : Blu-ray

Audio #1
ID : 2
ID in the original source medium : 4352 (0x1100)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Variable
Bit rate : 1 454 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless
Stream size : 1.22 GiB (3%)
Title : Stereo
Language : Japanese
Default : Yes
Forced : No
Original source medium : Blu-ray

Audio #2
ID : 3
ID in the original source medium : 4352 (0x1100)
Format : DTS
Format/Info : Digital Theater Systems
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Constant
Bit rate : 768 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossy
Stream size : 658 MiB (2%)
Title : Stereo
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Audio #3
ID : 4
ID in the original source medium : 4353 (0x1101)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Variable
Bit rate : 3 287 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless
Stream size : 2.75 GiB (7%)
Title : Surround 5.1
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Audio #4
ID : 5
ID in the original source medium : 4353 (0x1101)
Format : DTS
Format/Info : Digital Theater Systems
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Constant
Bit rate : 1 509 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossy
Stream size : 1.26 GiB (3%)
Title : Surround 5.1
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Audio #5
ID : 6
ID in the original source medium : 4354 (0x1102)
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Variable
Bit rate : 1 602 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless
Stream size : 1.34 GiB (4%)
Title : Stereo
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Audio #6
ID : 7
ID in the original source medium : 4354 (0x1102)
Format : DTS
Format/Info : Digital Theater Systems
Codec ID : A_DTS
Duration : 1 h 59 min
Bit rate mode : Constant
Bit rate : 768 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossy
Stream size : 658 MiB (2%)
Title : Stereo
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Text #1
ID : 8
ID in the original source medium : 4608 (0x1200)
Format : PGS
Codec ID : S_HDMV/PGS
Codec ID/Info : Picture based subtitle format used on BDs/HD-DVDs
Duration : 1 h 58 min
Bit rate : 32.0 kb/s
Count of elements : 2469
Stream size : 27.2 MiB (0%)
Language : Japanese
Default : No
Forced : No
Original source medium : Blu-ray

Text #2
ID : 10
ID in the original source medium : 4609 (0x1201)
Format : PGS
Codec ID : S_HDMV/PGS
Codec ID/Info : Picture based subtitle format used on BDs/HD-DVDs
Duration : 1 h 57 min
Bit rate : 26.8 kb/s
Count of elements : 1981
Stream size : 22.5 MiB (0%)
Language : English
Default : No
Forced : No
Original source medium : Blu-ray

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00:00:00.000 : ja:Chapter 01
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