Black screen on Doremi servers

Anything and everything to do with DCP-o-matic.
IoannisSyrogiannis
Posts: 86
Joined: Mon Nov 13, 2017 8:40 pm

Re: Black screen on Doremi servers

Post by IoannisSyrogiannis »

I don't have an opinion on what the problem is.
I always considered doremi servers (DCP2XXX or SV3/4) to be less strict than -say- dolby DSS ones on what they play. But then again, that might have to do with the root cause...

If it was me and I wanted to check whether the problem lies with the bandwidth, I would make three different parts, two (before and after) with the same bitrate and a different one on the part in question, that seems to not be demanding. I would then add the three CPLs into one, like if they were reels and re-wrap without re-encoding (ah... if we could keep the reels intact without re-wrapping! :-Þ). That should keep the different bitrate of the parts and give an indication (maybe not a certainty) on whether the bitrate is the culprit here.
Dark
Posts: 7
Joined: Mon Nov 29, 2021 10:21 pm

Re: Black screen on Doremi servers

Post by Dark »

Ok j2c unpacked. And most of the files are 950 - 1017. Only extreme of 1k files are pure black with disolve in which scene start and ends, but they are nowhere close to fault (about 500 frames from it)

I also learned that the new DCP fixed the bug in the doremi cinema, but not in the Cube server cinema.

One general question, from what source is it best to produce DCP? I always made it from DPX to preserve full data levels. Because most movies in our studio are shot on Alexa cameras in 12b and Log colorspace. So I always wanted to maintain the highest quality.

Is there any other test which I could try to do?

Thank you
carl
Site Admin
Posts: 1638
Joined: Thu Nov 14, 2013 2:53 pm

Re: Black screen on Doremi servers

Post by carl »

Is it possible to send me the J2K files of a hundred or so frames either side of the fault? Do you know exactly where it happened?
Dark
Posts: 7
Joined: Mon Nov 29, 2021 10:21 pm

Re: Black screen on Doremi servers

Post by Dark »

carl wrote: Fri Dec 03, 2021 9:41 am Is it possible to send me the J2K files of a hundred or so frames either side of the fault? Do you know exactly where it happened?
Hi,

ok i got it approved i can send it to you.
Can I send it to you by PM? Or somehow privately?
carl
Site Admin
Posts: 1638
Joined: Thu Nov 14, 2013 2:53 pm

Re: Black screen on Doremi servers

Post by carl »

Great, thanks! carl@dcpomatic.com is probably easiest.
Dark
Posts: 7
Joined: Mon Nov 29, 2021 10:21 pm

Re: Black screen on Doremi servers

Post by Dark »

carl wrote: Wed Dec 08, 2021 11:33 am Great, thanks! carl@dcpomatic.com is probably easiest.
Done.
Thank you
Dark
Posts: 7
Joined: Mon Nov 29, 2021 10:21 pm

Re: Black screen on Doremi servers

Post by Dark »

Hi, did you have time to look at the files I sent?
Did you find anything?

Thakn you.
carl
Site Admin
Posts: 1638
Joined: Thu Nov 14, 2013 2:53 pm

Re: Black screen on Doremi servers

Post by carl »

Hi,
Sorry it took a while to get back to you. I did get the files - thanks for sending them! Unfortunately I didn't spot anything to explain the problem when I had a quick look. I'll take another closer look as soon as I can.
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