Topic: Strange dropped frames on Mac

I noticed that playing video in mpv was smooth during low motion scenes but in higher motion it was mostly smooth but really jittery. I decided to run mpv from terminal to see the output and it turns out it's dropping frames like mad. Here is the odd bit - in the SVP Control Panel, if I select the Frame Size panel it puts a blue frame around the picture but the dropped frames completely stop, and the motion is as smooth as can be. If I go back to Video Profiles from here, the dropped frames start again immediately, or the a/v goes completely out of sync and I have to restart the video.

In Frame Size I have both Crop and Alter Video set to disabled and Black bars detection turned off, so it's not actually doing anything. The only thing I can think is that it's rendering differently in order to place the blue frame around the video?

If I start the video in Frame Size and leave it there, it's perfect (I just have to ignore the blue frame).

2 Reply by velinn (edited by velinn 04-12-2016 19:19:57)

Re: Strange dropped frames on Mac

I found a fix.. it's an mpv issue, and has nothing to do with SVP it would seem. I was going to delete this post, but I'll leave it in case anyone else has this issue. The solution is adding this to your mpv config:

opengl-early-flush=no
video-sync=display-resample

After adding these I get the occasional dropped frame which is no big deal. Still strange that there are no issues when in the Frame Size menu, but these two options seem to do the trick.

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Re: Strange dropped frames on Mac

velinn
One note: When you see blue rectangle over the video (Frame Size panel is active) SVP doesn't calculate new frames. All frames with blue rectangle are source frames. wink

  • Thanks: 7

Re: Strange dropped frames on Mac

Wait, no, stop.
opengl-early-flush=no is what should fix your issue (it's also mentioned on the wiki page).
video-sync=display-resample is a no-op when SVP interpolates to your display's refresh rate. I would definitely not enable it to prevent side issues due to display-resample machanics in mpv. After all, in this case there are 2 different programs trying to interpolate your video independently.

5 Reply by rorando (edited by rorando 03-01-2017 12:34:58)

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Re: Strange dropped frames on Mac

Hey guys,

thank you very much!

I am on OS X El Capitan and had the same problem. When running mpv from command line, the "dropped:" count was increasing consistently while playback. Adding the option

opengl-early-flush=no

fixed it!

Thanks again and best regards.