Failed recordings on BBC3 HD and BBC4 HD

[MontysEvilTwin]

To add to the above:

Install the auto-unprotect package. In addition to removing the protection flag from high def. recordings it will fix wrongly set HMT flags (those that cause recordings to be scrambled on playback).

Run the 'fixencflags' diagnostic. This will sort out most problem recordings that haven't already been fixed by auto-unprotect.

In rare cases, a file can be incorrectly labelled as decrypted when it is not, with the mislabelling in the TS file rather than the HMT (see here). The solution here is to use the HMT tool to manually remove the 'Dec' flag and then decrypt.

There have also been reports of units temporarily losing their decryption keys, with any recordings made while in this state scrambled on playback. There is no known fix for this but is is a very rare occurrence.

 

[Trev]

That's twice you have said that

 

[Black Hole]

There have also been reports of units temporarily losing their decryption keys, with any recordings made while in this state scrambled on playback. There is no known fix for this but is is a very rare occurrence.

...which we are still awaiting positive proof of.

If the encryption/decryption key(s) become corrupted, existing (encrypted) recordings will fail to play (and become totally scrambled if decrypted in this state), but new recordings will still play and decrypt - until a reboot (or possibly full cold start) which restores the key(s) and then renders undecrypted recording made while in the errant state useless.

What is needed is somebody who is alert to this able to investigate and confirm the above predictions before hitting the emergency off button (have you tried turning it off and on again), but it is a rare occurrence and normally hits somebody who has no idea what is going on, or if they do know what is going on is under other pressures to restore normal function again ASAP.

 

[alexp]

Thanks BlackHole & MontyEvilTwin for your last posts. It makes clear all the options.
I've already spent a fair time trawling through the previous posts etc to get an overall picture. Anyone new coming here will just want clear instructions what to do.

I presume that if you are not bothered about removing protection from HD recordings, you can just run fixenflags from the WebIF diagnostics and skip installing auto-unprotect?

If doing fixenflags just for one recording, is there any risk to the others?...

...because I was alternatively thinking about just fixing the scrambled recording using Telnet, eg

putty blah blah cli humax#
cd "/media/My Video"
ls -la
-- CLEAR the DEC flag
hmt +encrypted filename.hmt
-- what does the following do?
hmt -shrunk filename.hmt

 

[alexp]

... but I don't have a duff recording at the moment. I'm setting BBC4 every day hopefully wishing for failure (!!!).
The hot candidate is Leeds Piano Competition on 25th, as I lost part 1 last week (and deleted it!)

 

[MontysEvilTwin]

That's twice you have said that

?

 

[MontysEvilTwin]

Thanks BlackHole & MontyEvilTwin for your last posts. It makes clear all the options.
I've already spent a fair time trawling through the previous posts etc to get an overall picture. Anyone new coming here will just want clear instructions what to do.

I presume that if you are not bothered about removing protection from HD recordings, you can just run fixenflags from the WebIF diagnostics and skip installing auto-unprotect?

If doing fixenflags just for one recording, is there any risk to the others?...

...because I was alternatively thinking about just fixing the scrambled recording using Telnet, eg

putty blah blah cli humax#
cd "/media/My Video"
ls -la
-- CLEAR the DEC flag
hmt +encrypted filename.hmt
-- what does the following do?
hmt -shrunk filename.hmt

Just run fixencflags. It will scan your whole 'My Video' folder but all it does is make the flags in the hmt file match the state of the recordings. Those hmt commands you quoted were for a specific example and might not fix your problem.

 

[Black Hole]

Just run fixencflags.

^ What he said. Cut out the over-thinking.

 

[cdmackay]

... but I don't have a duff recording at the moment. I'm setting BBC4 every day hopefully wishing for failure (!!!).
The hot candidate is Leeds Piano Competition on 25th, as I lost part 1 last week (and deleted it!)

I recorded that, HD, and mine was fine. If that tells you anything...

 

[Owen Smith]

What does the badnts package do? I have auto-unprotect and auto-decrypt running, I thought they fixed everything that was fixable as well as decrypting.

 

[Black Hole]

No, they don't. The fixencflags diagnostic checks that the Enc and Dec flags are in the right state (and corrects them if not) by analysing the actual content of the .TS file. The problem with the miscreant BBC THREE HD and BBC FOUR HD (and others) recordings is that the .nts file is screwed up and need recreating before anthing else can be done to rescue the recordings.

I might have got the details slightly wrong, but reading through this topic from the start will provide your answer.

 

[prpr]

No, it's the .hmt file that's screwed up, at least on the latest firmware. Older firmware created zero length .nts files, which is what badnts dealt with.

 

[Owen Smith]

No, it's the .hmt file that's screwed up, at least on the latest firmware. Older firmware created zero length .nts files, which is what badnts dealt with.

I'm on the latest Humax firmware. Sounds like badnts won't do anything for me then.

I have read this thread from the start (again) and it doesn't make things clear to me at all.

 

[MontysEvilTwin]

I'm on the latest Humax firmware. Sounds like badnts won't do anything for me then.

I have read this thread from the start (again) and it doesn't make things clear to me at all.

As you are on the latest firmware (1.03.12) you are correct that you don't need the badnts package. The auto-unprotect package has been updated and will now fix the common hmt file errors that occur. If you are unlucky and still get a scrambled recording, try running the 'fixencflags' diagnostic.

As this is the non-customised section, errant hmt files can be repaired by copying them by ftp and editing with a hex editor. The hmt file format is described in detail in the wiki.