Choppy playback in DCP-o-matic Player

[dor]

Hey! I put a 24fps mp4 file into the software. Just with some default settings, nothing fancy. The playback in the software (not the player) looks great, but when I look at the result with DCP-o-matic Player - It's choppy, skips frames and all stuck. When I set it to "decode at quarter resolution" and play a part of it a couple of times - eventually it plays smoothly.

If I play it again and again, eventually I can get a smooth result, even with high resolution. What do you think? Is this unusual?
I've tried in on a MacBook pro 16" 2019, and on an asus asus gl502vy.

Thanks in advance,
Dor

[Carsten]

After you have loaded the DCP into player - what frame rate does the player report (lower left)? Is this a 4k or 2k DCP?

Choppy playback, unfortunately, is a known problem, at least on high-res monitors, and especially Macs. Setting decode to quarter res usually works, but may still be slow in full screen. If you haven't done so, try the latest test release (for Mac, you can download/install the player as a separate item), and choose 'openGL' in prefs->Display Mode.


If the source frame rate is 24fps, and the DCP as well, there is usually nothing to worry, it is only a player problem, you won't experience that in a cinema.

- Carsten

[dor]

Thank you Carsten, for the quick response. I'll make sure the file runs smoothly with the festival once they get it

[macuser]

I would like to chime in here: 'I'll make sure the file runs smoothly with the festival once they get it'

I have an over ten year experience with DCP's as I work for a film festival and I am responsible for the ingest process of all delivered DCP's.

We ingest all DCP's on the HD packages for 9 screens in advance (before the festival) so that the projectionists don't have to ingest anything during the festival. Loading (ingest) the film sucessfully on the servers does not mean it will work properly on the screen. That part is fully on the side of the producer of the DCP - it should be 100% tested in a cinema environment - a festival is not a 'Testhouse' and has no time for that.

Kind regards
Max

[funkytwig]

My understanding is you need a fairly beefy computer with a very fast HD (possibly a very fast SSD). DCP playback is VERRY demanding. Maybe this is why.

[carl]

It's more the CPU that's the limiting factor in most cases (rather than the HD/SSD), though things are improving (the 2.16.x player should be a fair bit better than the 2.14.x one, especially on macOS if you use the "OpenGL" backend).

[moontaurus]

Can you use the same libraries that mpv uses? mpv plays 4k j2k mxf flawlessly on my intel Mac, while DOM Player is very choppy, whether using software or openGL. Or have an mpv type engine as an option?