Audio Delay

Anything and everything to do with DCP-o-matic.
Carsten
Posts: 2665
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio Delay

Post by Carsten »

I am trying to think of an easy way to check a sync point within the actual DCP - common playback methods can not confirm this. Currently, one 'easy' method would be to count the frames towards a visual sync cue (e.g. flash frame), load the audio MXF e.g. into Audacity and count the time/frames towards the corresponding audio cue. That would nail it on the file side of things.

- Carsten
carl
Site Admin
Posts: 2362
Joined: Thu Nov 14, 2013 2:53 pm

Re: Audio Delay

Post by carl »

Agreed with Carsten, if you can make available either a DCP that is out-of-sync or a source file which makes an out-of-sync DCP we can investigate.
Alex Asp
Posts: 92
Joined: Mon Apr 11, 2016 3:59 am

Re: Audio Delay

Post by Alex Asp »

I can send you one. The only problem it is about 50 Gb in size
Carsten
Posts: 2665
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio Delay

Post by Carsten »

What kind of DCP is that? A regular one with obvious sync problems, a synctest DCP?

A simple synctest DCP would only need to have a few Mbytes (probably a few hundred kilobytes compressed), as there only need to be black frames and silence, with a few regular flash frames and beeps.

- Carsten
Alex Asp
Posts: 92
Joined: Mon Apr 11, 2016 3:59 am

Re: Audio Delay

Post by Alex Asp »

maybe, but that is not a real life test, and therefore won't help much.
But I can send it to you on a Blu-ray disc.
Probably should have mentioned that the problem was in DOM 2.10.12. Haven't tested it on newer versions.
Also , it seems to be less problematic if the DCP is not divided into (arbitrary) reels.
Carsten
Posts: 2665
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio Delay

Post by Carsten »

So, what type of content is that? A commercial Bluray RIP that shows sync issues after conversion to DCP?

- Carsten
Alex Asp
Posts: 92
Joined: Mon Apr 11, 2016 3:59 am

Re: Audio Delay

Post by Alex Asp »

Yes it is, but there his a catch. I have never seen commercial Blu-rays from Warners that display this problem. Universal titles, especially simple titles for older movies do. Some European discs also display this problem. In general. the cheaper is Blu-ray production, the higher the probability of sync issues after the conversion. Probably has to do with Blu ray authoring software.
Carsten
Posts: 2665
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio Delay

Post by Carsten »

I will try to look up some of my Blurays for suitable sync cues.

- Carsten