UHD FAQ

[preserve]

Please read this FAQ before you post. This FAQ contains answers to many common questions. You may also want to check out the main MakeMKV FAQ.

FAQ Last Updated: Mar 7, 2021

UHD Forums

Posting Guidelines
- Use the UHD drives subforum for drive-related questions.
- If your problem is related to a UHD disc, search this UHD forum for the name of the movie or TV show. If there's an existing thread, add to it. If you don't find an existing thread, make a new thread with the title of the movie or TV show as the subject of the thread. This increases the chance that someone who owns the same disc will see the thread and help you, and it helps others having the same issue to find related threads in the future.
- Otherwise, make a new thread if you have a general usage question.
- Include as many details, such as screenshots and/or MakeMKV's console/debug log, as possible.
- Don't use short and generic thread titles such as "help" or "subtitles". Always be specific in your thread title and in your message.

UHD Basics

I'm new to MakeMKV - what should I do first?
Turn on Expert Mode in Preferences -> General. Expert Mode is really not complicated, and options and functionality being discussed in the forums will make more sense if you have Expert Mode turned on.

Which version of MakeMKV works with UHD discs?
Starting with version 1.10.8, MakeMKV added support for UHD - but you should always use the latest version for important updates and bug fixes. For UHD support, there have already been several new versions with important updates that have made the previous versions obsolete. MakeMKV is frequently updated, so check here for the latest version. If for some reason you want to revert to an older version, you can find some older versions here.

Which drives work with UHDs?
You need a BDXL-compatible LibreDrive drive, which includes most "official" and all "friendly" UHD drives. Check out the UHD drives subforum and the UHD Drives Guide thread. (Originally, the drive with the most reported success was the ASUS BW-16D1HT.)

How do I know if a UHD is native 4K or an upscale?
Check this super handy thread! The spreadsheet contains a lot of useful information about UHD releases.

Hashed Keys

How does MakeMKV work with UHDs?
MakeMKV uses Hashed Keys. Originally supplied via a download, MakeMKV now updates automatically. Go to View / Preferences / General and ensure that "Enable Internet access" is checked.

MakeMKV says that "the volume key is unknown for this disc"?
MakeMKV produces an AACS .tgz dump file whenever you try to open a disc for which the key is unknown, and will report that the dump has been created. Email the dump file to svq@makemkv.com.

I submitted a dump, how long does it take?
Once submitted, the turnaround can be pretty fast, between 12 to 48 hours. However, it can also sometimes take several days or longer.
When you submit a dump, ensure that:
- You are using the latest version of MakeMKV.
- You are using a LibreDrive-enabled drive (be it "friendly" or "official", but it must be LibreDrive enabled).
- You have "Enable Internet access" enabled in Preferences (in the General tab), so that MakeMKV will check for updated keys when you try to open the disc again.
- You are opening the original disc (not a backup, not ISO).
- You are opening the disc using a real disc drive natively (no elby clonedrive, no vmware, no dvdfab or discsoft virtual, etc).

I see an "Automatic HK downloading is disabled or failed" error, how do I fix this?
Assuming you've enabled Internet access as mentioned above, you may have a DNS or Firewall issue. For detailed help on this, please read the Fixing Volume Key thread.

I see a movie discussed in the forum, but MakeMKV won't open my disc.
There are multiple versions of UHDs for each movie (countries, retailers, rentals) and there may be multiple keys for even the same version, so it's possible that your particular disc isn't decrypted yet. Submit the dump file!

Is there a way to "test" a disc to make sure the disc is good?
If you're waiting after submitting a dump, you can use MakeMKV's Backup function to copy the entire undecrypted disc to your hard drive in order to test that the UHD itself is good, and then once the key is available, you can use MakeMKV to open the disc backup off your hard drive. When you start MakeMKV, don't open the disc - just push the Backup button, an icon with a green arrow pointing into a yellow folder, second-from-left in the top row of icons.

Playlists

I see multiple titles for the main movie, which one do I choose?
Just as with Blu-ray discs, there may be multiple titles on the disc for varying reasons:
- If the disc has multiple cuts, such as theatrical vs extended.
- Look at "Source file name" - one may be the mpls playlist with chapters (this is the one you want), the other the m2ts source file.
- Disney discs (including Marvel and Star Wars, and some other studios have followed) will have multiple titles where the difference is localization for the titles and credits. English will be 800, other languages will be 801, 802, etc. (Some older discs might be something like 200, 201, 202, etc.)
- Look at the included audio/subtitle tracks. Some discs have one playlist for English/French/Spanish/etc, and a second playlist for English/Japanese.

Problems

MakeMKV reports MEDIUM ERROR or "corrupt or invalid at offset" errors while ripping.
This means that MakeMKV cannot physically read the medium (the UHD disc). This is usually due to either the disc not being perfectly clean (check your disc thoroughly from different angles under a bright light and carefully use a soft dry microfiber cloth to clean it) or it could be due to a defective disc, which can happen with all disc-based formats. Read more on this topic here: viewtopic.php?f=8&t=15055

When I watch a UHD rip, how come I see blockiness, or the audio stutters, or the framerate won't keep up?
Some recommended playback software has been http://mpv.io or http://mpc-hc.org with madvr. Also, check out our UHD Processing thread for discussions on reducing bitrate with software such as Handbrake. VLC generally has not been up the task yet, and isn't recommended.

How come my powerful computer (insert specs here) can't play MKV files smoothly?
A bit of technical explanation: On Blu-ray, each h.264 frame is encoded as 4 independent slices - this means that it is possible to decode any given frame using 4 parallel tasks. On UHD, each HEVC frame is encoded as 8 independent slices. Hardware decoders take advantage of this, but open-source software decoders don't use such acceleration. That's why a smart TV can easily play a high-bitrate HEVC from UHD, but could fail even on much lower bitrate MKVs from Handbrake. (Thanks to Mike for the info!)

When I watch a UHD rip on my computer or on a non-HDR TV, why are the colors muted or flat?
HDR UHDs contain metadata for the HDR. They also use Rec. 2020 / BT.2020, which is a 10-bit or 12-bit WCG (Wide Color Gamut) color space (compared to Blu-rays or SDR UHDs, which use the Rec. 709 HDTV color space). If you view HDR content on a non-HDR monitor, the colors will appear muted. Some playback software, such as http://mpv.io or http://mpc-hc.org / mpc-be with madvr, have various "tone mapping" methods to display the video - usually adequately - on non-HDR monitors.

KEYDB.cfg Volume Keys

I have a list of keys, can I post it here?
No. Mike has requested that keys should not be posted in these forums.

What about the old KEYDB.cfg method?
The KEYDB.cfg method still works with MakeMKV. You can put a KEYDB.cfg file in the MakeMKV data directory (specified in MakeMKV's Preferences). New volume keys can be simply added to the end of a KEYDB.cfg file with any plain text editor such as Notepad. But the easiest and fastest way to get your disc working is to submit dumps, and this also helps other users with the same disc.

Where can I find volume keys?
If you Google keydb.cfg, you'll find it.

How can I check if known volume keys for a movie match the specific disc I have?
Each volume key in the KEYDB.cfg file comes with a hash - specifically, it's an SHA1 hash of a file on the disc: AACS\Unit_Key_RO.inf. So just check the hash of the file on your own disc, and see if it matches any of the known keys for that movie.

[yorgo]

Thanks, preserve, excellent work. I would recommend one change, that you put a revision date, or "last revised", whatever, at the top of the post, something that states the last time you will have updated. We're in the "wild frontier" of UHD de-encrypting and processing so I expect that there will be numerous changes to how MakeMKV handles UHD discs over time (in a year or two, I can envision things being radically different).

I also request that the mods make this a sticky.

[gereral1]

When I watch a UHD rip on a non-HDR TV or computer screen, why are the colors muted?

HDR UHDs use Rec. 2020 / BT.2020, which is a 10-bit or 12-bit WCG (wide color gamut) color space (compared to Blu-rays, which use the Rec. 709 HDTV color space). If you view Rec. 2020 on a non-HDR monitor, the colors will appear muted. Some playback software, such as madvr have various "tone mapping" methods to HDR to SDR on the fly during playback. If you are converting your rips, also note whether or not your conversion software is converting the color space, as well as which tone mapping method the conversion software is using.

I spent 4 solid months writing a program called XDR. Google the Kodi HDR project to learn more. This is designed to play any HDR material on normal TVs and projectors removing the dull washed out color. Allows custom meta data in 8,10,24..... Bit float at UHD resolutions. Works on win 7,10 64 bit versions w/custom presenter evr filter in mpcbe 64bit. Written in visual studio. Automatic xdr cal detection in kodi and windows shell. This software does what madvr can do but playback is smoother. Can work to make Blu-ray rips look like HDR to by pumping up the levels past your TVs ability in the software......

[PaulCB]

When I watch a UHD rip on a non-HDR TV or computer screen, why are the colors muted?

HDR UHDs use Rec. 2020 / BT.2020, which is a 10-bit or 12-bit WCG (wide color gamut) color space (compared to Blu-rays, which use the Rec. 709 HDTV color space). If you view Rec. 2020 on a non-HDR monitor, the colors will appear muted. Some playback software, such as madvr have various "tone mapping" methods to HDR to SDR on the fly during playback. If you are converting your rips, also note whether or not your conversion software is converting the color space, as well as which tone mapping method the conversion software is using.

I spent 4 solid months writing a program called XDR. Google the Kodi HDR project to learn more. This is designed to play any HDR material on normal TVs and projectors removing the dull washed out color. Allows custom meta data in 8,10,24..... Bit float at UHD resolutions. Works on win 7,10 64 bit versions w/custom presenter evr filter in mpcbe 64bit. Written in visual studio. Automatic xdr cal detection in kodi and windows shell. This software does what madvr can do but playback is smoother. Can work to make Blu-ray rips look like HDR to by pumping up the levels past your TVs ability in the software......

You are mixing up WCG and HDR in this comment which was (incorrectly) used above. "If you view Rec. 2020 on a non-HDR monitor, the colors will appear muted." Rec 2020 (actually currently a bigger wrapper for the smaller DCI-P3 color space being delievered) is about Wide Color Gamut while HDR is about Contrast range (HDR10, DV) so combining them in that sentence that way is incorrect and misleading as they are two very different things. It could read "If you view Rec 2020 (WCG) content with a player that cannot support it or support remapping to your display which doesn't support it, it will appear muted." That said, I believe the issues is HDR, not Rec 2020 but I need to find the discussion on the topic before I can say for certain.
Eg would be what you see with VLC vs. MPC-HC/BE on standard computer monitor.

[preserve]

Yes, gereral1's comment quoted the FAQ but did not include the whole quote in the quote wrapper. It is hard not to conflate HDR and WCG because TVs are all about HDR and the term WCG is not often used or discussed, not to mention that each TV manufacturer has their own catchy marketing terms for levels of HDR/WCG compliancy. The technical details - and the different tone mapping curves used by different TVs, which make a huge difference - are not presented clearly to the consumer. That said, I will think about this some more with your suggestion and try to update the FAQ accordingly. Thanks PaulCB!

[preserve]

That said, I believe the issues is HDR, not Rec 2020 but I need to find the discussion on the topic before I can say for certain.

Any further thoughts?

I think it might be a combination of both factors, but I'm still scratching the surface and haven't yet got deep enough into the technical aspects to figure it out.

I looked up the "Ultra HD Premium" certification minimum specs, from the UHD Alliance, as a starting point. Obviously standard computer monitors (as well as many early 4K TVs - my Dad has one - before HDR was a thing) do not meet the specs in both the color and the HDR categories:

Devices
Image Resolution: 3840x2160
Color Bit Depth: 10-bit signal
Color Palette (Wide Color Gamut)
• Signal Input: BT.2020 color representation
• Display Reproduction: More than 90% of P3 colors
High Dynamic Range
• SMPTE ST2084 EOTF
• A combination of peak brightness and black level either:
More than 1000 nits peak brightness and less than 0.05 nits black level
OR
More than 540 nits peak brightness and less than 0.0005 nits black level

Distribution
• Image Resolution: 3840x2160
• Color Bit Depth: Minimum 10-bit signal
• Color: BT.2020 color representation
• High Dynamic Range: SMPTE ST2084 EOTF

Content Master
• Image Resolution: 3840x2160
• Color Bit Depth: Minimum 10-bit signal
• Color: BT.2020 color representation
• High Dynamic Range: SMPTE ST2084 EOTF

Recommended mastering display specifications
• Display Reproduction: Minimum 100% of P3 colors
• Peak Brightness: More than 1000 nits
• Black Level: Less than 0.03 nits

Non-HDR 4K discs are not as common, but they're out there. The only non-HDR 4K I have, Stranger Things UHD, also doesn't use BT.2020 - it's BT.709. So as you'd expect, it looks just fine on a regular computer monitor, TV or projector.

I'd be curious if there are any Non-HDR 4K discs that use BT.2020.

I've been thinking about importing the French Valerian 4K, which is also supposedly non-HDR, but I haven't seen that confirmed and I can't find any info about what's on the Blu-ray bonus disc which is what I'm mostly interested in - I've got it on my wish list and have been watching it, hoping for the price to go down.

[DavVador]

I've been thinking about importing the French Valerian 4K, which is also supposedly non-HDR, but I haven't seen that confirmed and I can't find any info about what's on the Blu-ray bonus disc which is what I'm mostly interested in - I've got it on my wish list and have been watching it, hoping for the price to go down.

I have the French Valerian UHD disc with bonus, i'll take a look later and tell you.
This is a non HDR version with BT.709 (says mpc). A bit sad other countries do have HDR while this french movie doesnt have in france

[bigtom]

Where is the file location to these dumps? No where does it say where on the file system to look for said dump file. If its in the .MakeMKV directory which is usually in your user directory then why when i get a failed to open disk do i not see my dump file to send?

[Woodstock]

Preferences->General will tell you where MakeMKV is putting data files. You can set it to wherever you want.

[zenon]

The FAQ explicitly says not to use VLC. Is VLC 3.0 any better?

[st4evr]

The FAQ explicitly says not to use VLC. Is VLC 3.0 any better?

From personal experience it’s not. They still have a long road ahead when it comes to UHD BD playback.

[Someoneelse]

VLC 3.0.4 seems to be usable with 4k rips. I tried 3.0.3 and it was choppy and unusable. 3.0.4, however, seems to be perfectly smooth, though I'm still having trouble with HDR. That could just be me. Can anyone else confirm that 3.0.4 works well with 4k?

[Billycar11]

VLC 3.0.4 seems to be usable with 4k rips. I tried 3.0.3 and it was choppy and unusable. 3.0.4, however, seems to be perfectly smooth, though I'm still having trouble with HDR. That could just be me. Can anyone else confirm that 3.0.4 works well with 4k?

i haven't had a problem with playback smoothness with anything over 3.0 but hdr to sdr tone mapping is still messed up for me

[Phrehdd]

I apologize if I am in the wrong area to ask but ...

With HDR, is the single MKV file created sufficient for playback (on a 4K tv that supports HRD) via Nvidia Shield TV? Do I need an entire backup of the UHD disc?

[SamuriHL]

With HDR, is the single MKV file created sufficient for playback (on a 4K tv that supports HRD) via Nvidia Shield TV? Do I need an entire backup of the UHD disc?

An MKV is perfectly fine for HDR playback on the SHIELD. Works in Plex, Kodi with no problems. No need to back up the whole disc.