Damaged frames / Pixel overlays since Catalina Update

Question

Level 1

13 points

Damaged frames / Pixel overlays since Catalina Update

Hi,

I'm facing a strange pixel overlay problem in iMovie. First I thought it has something to do with the transitions or the source videos, so I tried to delete them and put them back in the project, but the graphic issues remain or occur on different frames. I spent a couple of days now to somehow fix it, but in the end there were still those glitches, also in the exported files.

I see the glitches in the preview as well, but when I skim back a little and replay the same frames, it's gone. It reoccurs though, when I skim to a different part of the video and go back then to the problematic part.

Alena seems to have the same issue in FCP, see https://communities.apple.com/de/thread/250764098?page=1

Today I loaded older projects into the timeline and saw the same problems on those projects which worked totally fine before without errors, so I assume it is a Catalina problem / iMovie bug.

Some details:

iMovie 10.1.13 / MacOS 10.15.1
Videos taken with iPhone XS, 1080p, 60p
all source videos were imported to Apple Photos
no problems (glitches) anywhere else when playing those videos (Photos itself or playing from finder)
Video project is 4k / 30p, around 14 min.
I get around 10-12 pixel errors in the project, so it's practically useless

Anyone with the same issues or fixes?

Thx, Roman

MacBook Pro 15", macOS 10.15

Posted on Nov 2, 2019 2:03 PM

Reply

Answer 1

Top-ranking reply

Rich839

Level 8

47,730 points

Nov 3, 2019 7:33 AM in response to Rome@home

Hmmm. It might be related to the upgrades/updates as you say. Hard to tell. Nothing to do but trouble shoot

First try opening iMovie while holding down the Option and Command keys and selecting to delete preferences in the box that appears. iMovie will open in a new library. Return to your old library to get back to your project. Now see if the pixelation is still there.

If no luck, try opening iMovie in a new library and creating a project there to see if it works properly. To do that, open iMovie while holding down just the Option key. A box will appear giving you the option to create a new library in which iMovie will open. Copy your project into it and see if it works properly there.

If the problem still persists, try booting up in Safe Mode (see Finder help menu instructions) and, after everything loads, immediately shut down and reboot in normal mode. Then open iMovie and see if the project plays properly.

All else failing, try redownloading iMovie. Drag your present iMovie app from the Applications folder to the trash, but don't empty the trash. Then go to the online app store and redownload iMovie. If for some reason you can't get a redownload, you can drag your old iMovie back to the applications folder. If the redownload is successful you can empty the trash.

Hopefully one of the above will lead to a solution.

-- Rich

Reply

Answer 2

Rome@home Author

Level 1

13 points

Nov 3, 2019 3:00 PM in response to Rich839

Thanks for the quick response and helpful tips Rich!

I tried them all and also reset the NVRAM and SMC, still the same issues.

I came back to the transition thing and deleted them all in the project because most of those glitches are gone then, but the damaged frames occurred somewhere else in the end 😤

What I forgot to mention yesterday: My library is stored on an external Lacie raid, do people in this forum with the same issues also use external storage systems? When I tried the idea with a second library though, I created one on the Mac SSD and copied the project there, but the glitches remained, so I don't really see a connection here. I've never had any issues with the raid system before anyway.

Maybe I'll try a different project setting tomorrow with different fps or resolution and see what happens, but this is really frustrating...

Thx!

Reply

Answer 3

Exman_Sw

Level 1

8 points

Nov 8, 2019 9:53 PM in response to Rome@home

I have the exact same problem. Serious pixel overlay on multiple places in my timeline, both while editing and in the finished file. Have done two separate projects recently, both have the same problem. My clips are shot with iPhone XR. Have also added several GoPro clips in the same project, but these clips are unaffected.

Reply

Answer 4

Nov 16, 2019 10:25 AM in response to Exman_Sw

I too have the same problem. I used Catalina on a 13" MBP (2019) and have issues with pixelating multiple frames on editing and on exporting. I Airdropped the iMovie Library to a MBA running Mojave and had no problems with the file on editing or exporting. Both Macs are running iMovie 10.1.13 so I can only assume it's something to do with Catalina.

Reply