Level 1

14 points

Artifacts in iMovie

Hello all,

I have macbook pro 2017 base model with the latest Catalina MacOS and latest iMovie. I have created iMovie project on my iPhone 11 pro with latest osX and all the clips were recorded with this phone.

I wanted to finish my project on Macbook pro, so I airdroped project from phone to the macbook.

Now during editing in iMovie I can see some ugly artifacts during crossfade transition (or just after transition) from one shot to another one. This artifacts are visible in iMovie and also in exported video. Strange thing is, that after few plays of the shot in iMovie, artifacts disappeared. However, then they again appear after some time.

I've tried to delete transition and also shot and import it once again, however artifacts appeared again. I am not able to export video without visible artifacts. I can also see that in some artifacts I can see shot from another part of the project, upside down.

It's very strange, don't know if it is related to fact that project was airdropped from iphone or not. On the iPhone I can't see any artifact. I didn't do any video on the macbook directly so can't tell what's wrong, where is the issue, but for sure somewhere is pretty ugly bug - looks like graphic driver doesn't work properly. The strangest thing is that after few play of the part of the project, artifacts disappear for some time.

Posted on Oct 16, 2019 9:22 AM

Top-ranking reply

Rich839

Level 8

48,168 points

Posted on Oct 16, 2019 10:13 AM

Hi, geniusweb,

I don't think that Air Dropping the project caused this. Possibly a corrupt preference is causing it.

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. Reopen your old library to get back to your projects. Now see if the artifacts are gone.

Another thing you can try is to copy your media into a newly created project and see if that cures the problem. To do that, do an Edit/Select All, Edit/Copy, of the media in your project and then Edit/Paste it into the newly created project.

You could also try booting up in Safe Mode and, after everything loads, immediately shut down and reboot in normal mode. Then see if iMovie works properly.

-- Rich

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84 replies

Jan 20, 2020 4:43 PM in response to geniusweb

I'm having this same issue. I just exported whatever was in my Photos App (video shot on iPhone 11 Pro) and importing the videos from the Finder folder still seems to render artifacts though I haven't exported the actual iMovie as of yet.

Apple...it just works. No it doesn't...

Jan 31, 2020 5:48 AM in response to geniusweb

I have the exact same issue. Shot a bunch of content on my iPhone 11 Pro. Videos, Photos, Live Photos, both cameras. High efficiency are set for everything. Its ruining my videos. Its January 2020 and this is still a problem. Im not going to transcode my entire project before I edit it.

Rich839

Level 8

48,168 points

Jan 31, 2020 7:44 AM in response to azzurra1980

The poster timoytes, who has done the conversion from high efficiency would be the best one to comment on whether there is any quality loss. From the literature, the high efficiency formats have higher quality, but I don't know if it makes a significant difference. Best to try converting a test video or photo and see if you notice any difference.

-- Rich

Rich839

Level 8

48,168 points

Jan 31, 2020 9:21 AM in response to Rome@home

Reporting the bug is good. Apple does need to fix the artifact issue. As you have pointed out, issues at the architecture level of the software are beyond a consumer forum like this one. The tech engineers need to address it.

I suspect that Apple is working on this, since the problem goes to the functionality of the software. Meanwhile an "ugly workaround" is better than nothing, I suppose.

-- Rich

timoytes

Level 1

4 points

Jan 31, 2020 10:30 AM in response to Rich839

I don't think, that there is much of a quality difference.

That is the video with the converted clips: https://www.youtube.com/watch?v=Fm15Lmfxp8M&t=8s

There is some kind of color gradation in the blue starting at minute 6:32 ...

There was no color gradation in the original video. (recorded with iPhone 7, 1080p, 60 frames, hev)

Alvy

Level 1

4 points

Jan 31, 2020 12:42 PM in response to timoytes

Mmm that's not the same problem I think we have with the artifacs, that is more like

Yours seems to be more related to video quality (it's really good, by the way) and smooth transitions and low-light conditions maybe.

--Alvy

timoytes

Level 1

4 points

Jan 31, 2020 2:01 PM in response to Alvy

The video was rendered after I converted the single clips to mp4. But the question was, if the quality gets worse through the conversion process.

I had a lot artifacts when I was using the hev files imported from my phone.

Feb 6, 2020 11:28 PM in response to Rich839

Thanks for linking the discussions Rich! I also tried that as a first fix a couple of weeks ago and it looked pretty successful at first. But once I jumped to a different part of the timeline and then back to the problematic part, there where artifacts somewhere else 😤 Still it helped at some clips! Also eliminating some transitions helped with short clips in my project...

Unfortunately only sometimes 🤞🏻

arediddy

Level 1

8 points

Apr 5, 2020 8:02 PM in response to Metroknow

Hi there, thanks for your post. I tried what you did and exported my project as a .mov file in 1080 pro-res, but unfortunately the artifacts/pixels showed up in that file as well (just as they do in an .mp4 file). When you say you've done this workaround a dozen times, is it all on the same project or you've had success doing this with a dozen different projects?

DTyrel99

Level 1

4 points

Apr 28, 2020 10:28 AM in response to geniusweb

I'm getting this same issue. I record a lot of video clips with my iPhone 11 and try to edit them with iMovie and I'm getting a lot of artifacting, particularly when transitions occur. I have to speed up clips to make the movie shorter and that also seems to make it worse. This is a bad problem and we need a fix! I'm ready to purchase a new video camera and ditch the iPhone.

May 1, 2020 12:14 PM in response to defrian

FIXED!!! OK, whatever happened in the last couple of days - after defrian's post I checked my project too and had no artifacts in the project itself NOR in the exported file!

There were no software updates to Catalina or iMovie imho, so I have no idea what exactly happened - could it be some codec problems that were refreshed in some background update process?

Can anyone confirm for their projects?

thx, Rome.

don----

Level 1

4 points

May 1, 2020 1:00 PM in response to Rome@home

this is great news - I am glad both of you had positive results.

whatever the change was, it does not appear to have also happened in Mojave, I just re-exported my project and still have the artifacts. Maybe I will have to put on my big boy pants and jump into Catalina. Been holding out since it is a work laptop.

Defrian & Rome - Thanks for taking the time to post your findings.

MacBook Pro (15-inch, 2018)

10.14.6 (18G4032)

geniusweb Author

Level 1

14 points

Oct 20, 2019 11:12 AM in response to dpar4272

Do you use iPhone 11 shots in your projects? Now it looks like it’s not related to Catalina, so maybe it’s iPhone related issue. Or, iMovie issue - I am also using 10.1.13 version.

Nov 8, 2019 5:42 AM in response to geniusweb

I did try importing the whole iMovie project into final cut, but did not try removing the offending clips and adding them back in. I'll give that a try. Thanks!

geniusweb Author

Level 1

14 points

Nov 9, 2019 9:14 AM in response to Rich839

I have used only 1 photo in the video - at the beginning. You think this may be the issue (artifacts)?

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Artifacts in iMovie