Preferred Language

[skaleton]

Hi,
Sometimes multi language DVDs are structured around the 'Preferred Language' audio and sub-picture.
In these dvds English is 25966
Although my computer is set to US English, my preferred language in PgcEdit is 65535

Usually it doesn't matter but I have a dvd that stops after a few seconds of playing. Having done a Trace in PgcEdit, it appears that 65535 leads to a dead end. I ripped the dvd, I changed the pgc's related to the preferred language to 25966 and it worked.

I would appreciate if someone would explain how this preferred language works?
what language is 65535?
Why is my computer set to 65535 instead of 25966?
I changed the default language in Vista but it remained 65535 in PgcEdit.
whether and how to properly set up the preferred language?

Thanks in anticipation for your help

[bigotti5]

Why is my computer set to 65535 instead of 25966?
It is not your computer - you have to set up the trace player in Pgcedit (Trace - Virtual Player Setup) and not in Vista.

But you hint to a small inaccuracy in Pgcedit.
Default value for SPRM 1 (Preferred menu language) is "Player Specific" and not 65535.
65535 (= Not Specified) is the correct default value for SPRM 16 (Preferred audio language) and SPRM 18 (Preferred subtitle language).

[skaleton]

Thank you bigotti5 for your reply.
I have to admit that I have been using Trace but never looked at the virtual player setup. Very interesting.

So if I understand correctly, the problem is with the DVD navigation, not my configuration and it is ok to leave the preferred language not specified.

Actually I just tried playing it with WMP instead of PowerDvd, or mpc-hc and it works. So now, why would it work with WMP but no the other two players, that usually play dvd's fine?
The settings seem ok, as far as I can tell.

This is all confusing.

[bigotti5]

So if I understand correctly, the problem is with the DVD navigation, not my configuration and it is ok to leave the preferred language not specified.

It means every player must have a value from ISO639 (two byte, coded as lower case ASCII characters) and not 65535. 65535 can lead to a dead end...

[skaleton]

Would that mean that WMP is set up correctly but there is an issue with the other players?
PowerDvd language in user interface is set to default, I changed it to English but with same failed result. mpc-hc is set to English

[r0lZ]

bigotti5, do you mean that the preferred menu language do not obey the same rule than the other preferred language? If the user can opt to let the player decide which audio and subpic language to use, it seems logical to let it select also the menu LU. If it's the case, what value should hold SPRM 0 to indicate that the first LU should be selected instead of a LU in a specific language? Again, 0xFFFF seems logical.

Also, I don't understand why 0xFFFF could lead to navigation errors. If there are several LUs in the DVD and SPRM 0 doesn't match any of their codes, the player should use the first LU. Right? So, whatever code is configured should work, even if it is not in the list of recognized language codes. Same thing if the author tests SPRM 0. He cannot compare it to all valid codes without exception, and there must therefore be a fallback point somewhere. So, IMO, if a DVD doesn't work with a specific player, that's probably due to an authoring error, or a bug in the firmware or nav filter.

Am I wrong?

[bigotti5]

bigotti5, do you mean that the preferred menu language do not obey the same rule than the other preferred language?
My records say so..
No. Description Access Values Default Value
0 Preferred menu language Read-only Two lowercase ASCII letters Player-specific
...
...
...
16 Preferred audio language Read-only Two lowercase ASCII letters 65,535 (FFFFh)
or 65,535 (none)
...
18 Preferred subpicture language Read-only Two lowercase ASCII letters 65,535 (FFFFh)
or 65,535 (none)
...

[r0lZ]

Thanks, but "Player-specific" doesn't mean much. In particular, it doesn't mean that 0xFFFF (or 0 or anything else) is forbidden.

And do you agree with what I've said about the nav errors? I still don't understand why using 'en' (for example) instead of 0xFFFF in SPRM 0 could be safer. If the DVD has not been authored for the English market, and if there is no default case for handling unsupported default language codes, it may crash also. Right? Imagine what happens if an user selects the 'zu' (Zulu) code! Is it really safer than 0xFFFF?

So, IMO, leaving 0xFFFF (undefined) in SPRM 0 is a good way to discover some authoring errors. Why should I prohibit that?

[mpucoder]

Are you sure everyone is talking about the same problem? The way I read it the VM is getting lost trying to process the contents of SPRM0 (rather than let the player pick the LU by its rules) and that is an authoring error (not allowing for fail-safe no-match cases)

[r0lZ]

I agree, and it's what I've tried to explain in my bad English.
Unfortunately, there are many commercial DVDs that use the content of GPRM0 to decide which PGC or PG to play. Not a good idea imo, but that's possible and legit, right?
So, you confirm that the bug is caused by a bad authoring, and not by the content of SPRM 0, that can be virtually anything?

[mpucoder]

If you look at the "allowable values" it should be an iso 639 language code. But I also feel that VM code should follow good programing practices.
Bottom line, though, is if the VM code fails you can either fix the code or set the virtual player default to one that the code expects.

[r0lZ]

OK then. I'll change the PgcEdit default to 'en', and remove the possibility to "unset" SPRM 0. But I hate to have to do that. IMO, there is no valid reason to favour 'en' instead of, say 'zu'! And doing so will hide the authoring error. Not sure it's a good thing.

[bigotti5]

Did some investigation on certified tracers.
Scenarist uses 0x7A7A as "not specified"
DVDAfterEdit uses 0xFFFF
DVD Preplay allows ISO639 only...

:confused: :D

[r0lZ]

0x7A7A = "zz". Makes sense to use only ASCII characters imo.
But who is right? (Of course, I like the AfterEdit way!)