Decryption Problem

[BMAX]

I recently recorded "Mamma Mia-Here We Go Again" (OK, I know! but I love ABBA) and hit a small problem with decryption.

Pressing OPT/decrypt, I got the decryption pop up and the progress bar as normal, but at 100% complete nothing further happened. Going back to "Browse" the recording was shown as still encrypted and the newly created "original" file was empty. I retried several times, after trying reboots, power cycles etc, with the same result.

The only things that seemed different to normal were the very long title and the long (5.22GB) file length I shortened the title to "Mamma Mia 2" to see if this was the problem and the file successfully decrypted. Unfortunately I then realised that I had accidentally copied the renamed file to a recursive decrypt folder instead of a stand alone file Hence having made two changes, I do not know what the original problem was and can only find out by repeating the whole process.

Does anyone Know if a long file name or a large file can cause this problem?

 

[Black Hole]

Pressing OPT/decrypt, I got the decryption pop up and the progress bar as normal, but at 100% complete nothing further happened.

This has been reported before, and it seems to be a bug. An alternative is to tick the selection box for that recording, then queue selected recordings for decryption at the bottom of the page.

 

[/df]

Here, in fact.

If you come back to the machine later (say the duration of the show, or a bit more for software-based decryption), you should find a decrypted version of the show with ".decrypting" appended to the file name. The .ts file should have the same size as the encrypted version.

You might hope that sweeper could be used to tidy this up, and it can, provided you're happy to overwrite the encrypted original rather than moving it to a subfolder or deleting it to the dustbin.

 

[BMAX]

Thanks for your input. I am afraid the link you posted is way above my pay grade, being a mere long retired hardware engineer. Over the years I have decrypted well over 2500 files successfully and not noticed this problem before, but the vast majority have been using the recursive decrypt facility, if this is relevant.
I am happy now that I have a decrypted file and was only asking out of interest. As an aside , the decrypted version's audio stutters regularly during the long final credits, the video and audio seem to lose synch and it looks like Video Redo has inserted dummy audio frames every few seconds to allow the video to catch up. I am not bothered about this but never having seen this effect before, I would like to know what is going on.

 

[MymsMan]

Thanks for your input. I am afraid the link you posted is way above my pay grade, being a mere long retired hardware engineer. Over the years I have decrypted well over 2500 files successfully and not noticed this problem before, but the vast majority have been using the recursive decrypt facility, if this is relevant.

Now that we have the Queue for Decryption option on Browse menu the old while you wait decryption from the Opt+ menu is obsolete and it would be better to retire it than to investigate why it might fail in some case

 

[/df]

Thanks for your input. I am afraid the link you posted is way above my pay grade, being a mere long retired hardware engineer. Over the years I have decrypted well over 2500 files successfully and not noticed this problem before, but the vast majority have been using the recursive decrypt facility, if this is relevant.

It's just manually initiated operations that are affected, including Opt+>Decrypt.

TL;DR: the software process on the Humax that runs the decryption (eg) gets terminated leaving the operation running, because the server managing the process only gives it 6 minutes to return a result.

... the old while you wait decryption from the Opt+ menu is obsolete and it would be better to retire it than to investigate why it might fail in some case

However other manually initiated operations could also be affected, such as extracting MP3 sound from a long programme (or would be if the operation was protected by catch).

... As an aside , the decrypted version's audio stutters regularly during the long final credits, the video and audio seem to lose synch and it looks like Video Redo has inserted dummy audio frames every few seconds to allow the video to catch up. I am not bothered about this but never having seen this effect before, I would like to know what is going on.

Some discussion here may be relevant, but prepare to wrap your head in a cold towel if you found the previously linked post hard work.

 

[Black Hole]

I am afraid the link you posted is way above my pay grade

Then you don't need an explanation, just the knowledge of an alternative route to the desired result.

 

[BMAX]

I don't need an explanation, but a little insight into the cause is most welcome.

 

[Black Hole]

The cause is that something broke (presumably when fixing something else), nobody qualified has looked at it, and as that method has been largely superseded by other methods very few people care enough to bother.

 

[BMAX]

So why are you bothering?

 

[Black Hole]

You asked. But I'm not qualified to fix it.

 

[prpr]

I don't need an explanation, but a little insight into the cause is most welcome.

The maximum run time for something kicked off by the web server is 6 minutes, as /df has said.
This is set by the server.max-write-idle = 360 setting in the /mod/etc/lighttpd/server.conf file.
You can change the value to something higher if you like (and restart the server - service lighttpd restart from the command prompt - or reboot).
(It will get blatted though if/when the lighttpd package is updated.)

 

[/df]

But not if the modified setting is in /mod/etc/lighttpd/extra.conf, though, nor if it's in a file in /mod/etc/lighttpd/extra.d.

 

[BMAX]

Just to clarify things a little...

The decrypted file is not broken. It plays perfectly on the Box and on my PC. I understand the reasons for my original problem (hanging process) and, albeit accidentally, performed my decryption non manually. Thanks for the help given to explain this.

The stuttering happens following editing with VideoReDo and only occurs during the final credits.
As an experiment, I edited out the complete film and filed only the last few minutes of the credits. VideoReDo reported 2691 audio re-synch frames added. Replay stuttered regularly every few seconds.
It looks as though I should be talking to VideoReDo, but they no longer support my version.
Once again , thanks for the helpful replies