VLC cannot play one specific Blu-ray (AACS v76), but MakeMKV opens it successfully

[Alicey]

Hello,

I'm trying to play a commercial Blu-ray with VLC, but only one specific disc fails.

Environment:
- Windows 11 64-bit
- VLC 3.0.23 (official release)
- Also tested with VLC 4.0 nightly
- External Blu-ray drive: HL-DT-ST BP71NB10 (firmware 1.03)
- libaacs installed
- Latest KEYDB.cfg installed
- MakeMKV v1.18.4 installed
- MakeMKV successfully opens this disc without errors

Disc:
- Yorushika LIVE "Gekkou"
- Product code: UPXH-1079
- AACS version: v76

Problem:
The disc cannot be played in VLC.

Depending on the configuration, VLC reports either:
- "No valid Processing Key found in AACS config file"
or
- "Nothing to play"

What works:
- Another Blu-ray from the same artist ("Yorushika LIVE Zense") plays correctly in VLC on the same PC.
- The Gekkou disc plays correctly in Leawo Blu-ray Player.
- MakeMKV successfully opens the disc.
- Main title: about 20.4 GB
- 25 chapters detected.
- No errors are reported by MakeMKV.

Already tested:
- Latest KEYDB.cfg
- libaacs.dll
- VLC 4.0 nightly
- MakeMKV Integration (libmmbd)
- Replaced libaacs.dll and libbdplus.dll with libmmbd64.dll
- Directly opening the largest M2TS file
- Another Blu-ray ("Yorushika LIVE Zense") works correctly in VLC on the same PC
- Leawo Blu-ray Player plays this disc successfully

None of these solved the problem.

Is this a known compatibility issue between VLC/libbluray and this particular Blu-ray (AACS v76)?
If necessary, I can also provide VLC debug logs and MakeMKV logs.

Thank you.

[Sayaka]

This is very strange, since if the integration is done properly VLC should be able to open any Blu-ray disc that MakeMKV is able to open...

The "correct" possible workaround :

You could try making a decrypted backup of the disc, then turning that backup into an ISO file with IMGBurn (https://www.imgburn.com/ - be sure to use the UDF 2.50 file system when creating the ISO), and opening that ISO file with VLC.

The "not quite as recommended" possible workaround, but it would be interesting if it worked :

Would you mind downloading FindVUK 1.83 from the download link at the bottom of the first post in this thread : https://forum.doom9.org/showthread.php?t=172472 ?

Unzip it. Then install the trial version of DVDFab (https://www.dvdfab.cn/), close DVDFab, and run FindVUK.exe with the troublesome disc inside your Blu-ray drive (you may need to add an exception for FindVUK if you have antivirus software). Wait until the process is complete. Run "FindVUK - Synchronize.bat" afterwards, then try playing the disc again directly from the Blu-ray drive with VLC.

[Alicey]

Hi Sayaka,

Good news!

I followed your instructions:

Installed the DVDFab trial version.
Ran FindVUK 1.83.
Ran "FindVUK - Synchronize.bat".

At first, VLC still showed an infinite loading screen.

However, after trying again, it started working correctly.

The Blu-ray menu is displayed, the menu buttons work, and the movie plays normally in VLC.

Thank you very much for your help!

[Alicey]

Hi Sayaka,

Thank you again for your help.

FindVUK solved the original problem, and I can now play the Blu-ray in VLC.

However, I noticed that playback is not always consistent.
Sometimes the disc loads and plays normally, but occasionally VLC gets stuck on the loading screen or at the warning screen.

Restarting the PC seems to make it work again.

I just wanted to let you know in case this information is useful.

[Sayaka]

You're welcome ! It looks like VLC was unable to get the Volume Unique Key (VUK) from MakeMKV for some reason, and when you likely added it (or at least the Unit Keys) to KEYDB.cfg when you used FindVUK, it fixed this.

Sometimes the disc loads and plays normally, but occasionally VLC gets stuck on the loading screen or at the warning screen.

This happened to me as well in the past, in the following cases :

1) The drive wasn't getting enough power,
2) The disc hadn't been cleaned properly,
3) The drive had been flashed to a firmware which was having trouble reading the disc,
4) The disc itself was a "difficult" disc,
5) (Sometimes) I was using an LG drive instead of a Pioneer drive.

In short, the issue you're having sounds like your drive itself is having trouble reading the disc.

Restarting the PC seems to make it work again.

Good to know, thanks ! However, given the nature of this issue, I wouldn't be surprised if you ran into it again. If there's something you should try first and foremost, it would be 1) making sure the drive is getting enough power, and 2) making sure as few apps as possible are running in the background when playing the disc (odd as it may sound, I've had issues with this before).

[Alicey]

Thank you so much for all your help. VLC is finally working thanks to you. I learned a lot during this process. You're amazing! Hope to work with you again.
ARIGATO!!!!!!!!!!!

[Sayaka]

Thank you for the compliment !

ARIGATO!!!!!!!!!!!

I must confess I am not actually Japanese and picked my nickname for a variety of reasons.

That being said, I like Japanese culture a fair bit, so どういたしまして !

[tomty89]

It looks like VLC was unable to get the Volume Unique Key (VUK) from MakeMKV for some reason, and when you likely added it (or at least the Unit Keys) to KEYDB.cfg when you used FindVUK, it fixed this.

For the record, VLC / libbluray just passes the encrypted data to libaacs / libmmbd for decryption (in the case of libmmbd, the data is further passed to the makemkvcon "black box"). (Although I recently learnt that for title with BD-J / BD+, libbluray / libbdplus may try to obtain the VID and/or MK -- but not VUK.)

Once an entry is added to (the) KEYDB.cfg (libaacs reads), VLC / libbluray would be able to leverage libaacs instead of libmmbd for decryption. (No more "No valid Processing Key found in AACS config file".)

In other words, it seems that somehow libmmbd doesn't work well for certain / the specific title (even when MakeMKV can handle it fine).

[Sayaka]

It looks like VLC was unable to get the Volume Unique Key (VUK) from MakeMKV for some reason, and when you likely added it (or at least the Unit Keys) to KEYDB.cfg when you used FindVUK, it fixed this.

For the record, VLC / libbluray just passes the encrypted data to libaacs / libmmbd for decryption (in the case of libmmbd, the data is further passed to the makemkvcon "black box"). (Although I recently learnt that for title with BD-J / BD+, libbluray / libbdplus may try to obtain the VID and/or MK -- but not VUK.)

Thank you for correcting me, for some reason I sometimes forget that VLC doesn't actually get the VUK from libmmbd/MakeMKV.

Once an entry is added to (the) KEYDB.cfg (libaacs reads), VLC / libbluray would be able to leverage libaacs instead of libmmbd for decryption. (No more "No valid Processing Key found in AACS config file".)

True, and AFAIK (please feel free to correct me if I'm wrong) whereas MakeMKV needs the VUK to decrypt a disc, libaacs (and Xreveal) seem to work fine with just the Unit Keys, which is why as long as you can use FindVUK to get the Unit Keys for a UHD Blu-ray disc, you can then use Xreveal *and* MakeMKV simultaneously to make a decrypted backup (although sending the dump file is still recommended to make things easier for other people, of course).

[tomty89]

True, and AFAIK (please feel free to correct me if I'm wrong) whereas MakeMKV needs the VUK to decrypt a disc, libaacs (and Xreveal) seem to work fine with just the Unit Keys, which is why as long as you can use FindVUK to get the Unit Keys for a UHD Blu-ray disc, you can then use Xreveal *and* MakeMKV simultaneously to make a decrypted backup (although sending the dump file is still recommended to make things easier for other people, of course).

No idea. Wouldn't be too surprising though, as ultimately it depends on whether MakeMKV is even coded to attempt to read / use the Unit Keys in KeyDB. (I mean, it's not necessarily due to some sort of technical difficulties. Btw are there even entries in the public KeyDB that consists of Unit Key but not VUK? Can such entry be submitted?)

Don't know much about Xreveal. Does it basically "present" MakeMKV with a "decrypted virtual disc"? (I mean, probably you don't even need MakeMKV to "copy out the decrypted files"?)

[Sayaka]

Btw are there even entries in the public KeyDB that consists of Unit Key but not VUK? Can such entry be submitted?

There are, although I think these are submitted with FindVUK, not with dump files (dump files seem to always result in the VUK being uploaded).

Don't know much about Xreveal. Does it basically "present" MakeMKV with a "decrypted virtual disc"?

I believe Xreveal can break the encryption using the Unit Keys and let MakeMKV (or something else) do the rest, indeed.