Strange color noise in an actress' dress after conversion

Anything and everything to do with DCP-o-matic.
freezer
Posts: 27
Joined: Sun Jul 31, 2022 9:16 pm

Re: Strange color noise in an actress' dress after conversion

Post by freezer »

OK, the final situation is as follows:

After recreating the DCP in DOM 2.16.18 and DOM 2.14 as written before, I have put both unpacked folders onto an USB stick and brought that to the cinema. They tried to ingest both but only the DOM 2.14 version got ingested and played back successfully. The DOM 2.16.18 version threw an verification failed error after ingesting.
I have no idea why this happens with DOM 2.16.18, if this version itself does not create the problem, then it must be related to the workstation itself.
Bit flipping while the checksum process takes place or something like this?
Last edited by freezer on Thu Aug 11, 2022 8:32 am, edited 1 time in total.
Robert Niessner
Graz / Austria
Carsten
Posts: 2807
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Strange color noise in an actress' dress after conversion

Post by Carsten »

You can use DCP-o-matic player to verify the DCP before and after you copied it to the USB-Stick.

I haven't done much work with 2.16.18, but we never had any version of DCP-o-matic create corrupt DCPs. Well, we had, but in those few cases that I remember, it was always a hardware problem - defective memory, storage interface, picky ext2 filesystem driver, etc., but not the code.

Nothing wrong, however, for the time being, to use 2.14.59 if you feel better with it.
freezer
Posts: 27
Joined: Sun Jul 31, 2022 9:16 pm

Re: Strange color noise in an actress' dress after conversion

Post by freezer »

Thanks Carsten!
I've now used the DOM Player to verify the files.

Verifying the DOM 2.16.18 DCP on the workstation SSD shows no error. Verifying the same DCP from the USB stick throws:
The hash of the picture asset j2c_b4df7476-06f0-40d8-960a-1417446dcefd.mxf does not agree with the PKL file. This probably means that the asset file is corrupt.


The other DCP was copied over my 10Gbit network from the older workstation onto the same stick onto the new workstation.
So there must be something producing an error when copying from the internal SSD to the stick over copying from the LAN to the stick.
Always in the same USB port.

Where is Agent Moulder when you need answers...
Last edited by freezer on Thu Aug 11, 2022 8:33 am, edited 1 time in total.
Robert Niessner
Graz / Austria
Carsten
Posts: 2807
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Strange color noise in an actress' dress after conversion

Post by Carsten »

Probably something went wrong with the USB stick. Shouldn't, but it does happen.
freezer
Posts: 27
Joined: Sun Jul 31, 2022 9:16 pm

Re: Strange color noise in an actress' dress after conversion

Post by freezer »

I've made another copy of DOM 2.16.18 DCP to the stick and this time the DOM Player verified it fine.

So the lesson to learn is:
Always do a verify of the DCP after copying to a USB stick / drive via DOM Player.
Thank you all for your great help and support!

FYI: I've edited all posts to reflect that this is about version 2.16.18 not 2.18 as I wrote wrongfully.
Robert Niessner
Graz / Austria