Unusual FCPX problem – red line in timeline render bar

[Joe Marler]

[Hamdani Milas] “…Sometimes the clips export okay, sometimes the juddery playback or even a stalled frame is reproduced in the exported file…all ProRes video files…2015 27″ iMac to Mojave 10.14.6 and also updated all Pro Apps including FCPX10.4.8…I usually disable background-render, now and then select all and manually trigger a render but portions of the timeline often refuse to render leaving the usual white dots….Also deleted all library and/or project render files to no avail – the red lines persist. There’s no apparent action in any aspect of the workflow that appears to induce the red lines nor can I find any reliable or repeatable way to eliminate them.”

Very interesting case. I have never seen this; it is rarely reported and there’s no clear answer. You have already done the normal troubleshooting steps.

Can you examine the characteristics of that clip and compare that to the timeline characteristics? Does the frame rate match? Is the clip or timeline interlaced? Has any retiming or optical flow been used on that clip? What are the clip attributes – IOW if you play it in Quicktime and do CMD+I, what does the movie inspector show?

What camera did the ProRes material come from? Blackmagic cameras can embed a separate project frame rate vs sensor frame rate and sometimes that metadata makes FCPX behave oddly, but nothing like this.

If there are clips which sometimes cause the problem and other clips which never cause the problem it might be worth examining those side-by-side using Invisor’s comparison viewer: https://apps.apple.com/us/app/invisor-media-file-inspector/id442947586?mt=12

You can also verify you are on the latest version of Apple Pro Video Formats. Starting with Mojave that is done in System Preferences>Software Update.

Re Disk Utility, it will only run in advisory or read-only mode on the system drive unless the Mac is booted in Recovery Mode: https://support.apple.com/en-us/HT201314

After running that if you have never rebuilt Spotlight Indexes you can do this on each drive: https://support.apple.com/en-us/HT201716

I formerly had a 2015 iMac 27 and after a few years it showed erratic behavior but nothing like this. It passed Apple diagnostics but at the Genius bar they ran overnight bench diagnostics and it finally failed, requiring a logic board replacement. But normally a hardware issue would cause a hang or crash not an anomalous UI element.

It’s not a very stringent test but you could try Apple diagnostics: https://support.apple.com/en-us/HT202731

[Hamdani Milas] “…The red line phenomena also applies to new libraries created from scratch in projects with all ProRes video media..”

This is especially troubling and could indicate some external commonality. E.g, a plug in, system config issue or an incipient hardware problem.

Is all media on locally attached HFS+ or APFS drives, nothing on NTFS, ExFAT or NAS drives?

You might check if any 3rd-party kernel extensions are installed by typing this command in terminal:

kextstat | grep -v com.apple

[Hamdani Milas]

Hi Joe

Thanks very much for taking the time to read my post and for providing such detailed and useful suggestions. Here are the results of further checking:

[Joe Marler] “Can you examine the characteristics of that clip and compare that to the timeline characteristics? Does the frame rate match? Is the clip or timeline interlaced? Has any retiming or optical flow been used on that clip? What are the clip attributes – IOW if you play it in Quicktime and do CMD+I, what does the movie inspector show?”
All the red line problem clip characteristics match the project settings; frame rate 25fps, dimensions 1080 etc. All clips concerned are 1080p and either ProRes 422 or ProRes 422HQ, there are no interlaced clips and the project is also set to progressive. QT’s movie Inspector confirms the above. There is 2x retiming on the clip shown in the screen grab but red lines do also occur above clips, titles or transitions, with no retiming. Interestingly, if the retiming is reset to normal on that clip the redline shows on half the original duration and white unrendered dots on the other half.

[Joe Marler] “What camera did the ProRes material come from? “
These are not camera files, they are either master files, output from Final Cut Pro (earlier version) or After Effects renders.

[Joe Marler] “If there are clips which sometimes cause the problem and other clips which never cause the problem it might be worth examining those side-by-side using Invisor’s comparison viewer:”
I tried this and the clips compared show similar metadata and with nothing unusual apparent.

[Joe Marler] “You can also verify you are on the latest version of Apple Pro Video Formats. “
Yes, latest – Pro Video Formats ver. 2.1.1. I also notice several previous versions are also installed. Presume this is usual?

[Joe Marler] “Re Disk Utility, it will only run in advisory or read-only mode on the system drive unless the Mac is booted in Recovery Mode:”
Yes, Disk First Aid was run in Recovery Mode. Also booted in Safe Mood to run those under the hood routines as well.

[Joe Marler] “After running that if you have never rebuilt Spotlight Indexes you can do this on each drive”
Rebuilt the Spotlight indexes for the external media drive concerned. The red line problem persists.

[Joe Marler] “It’s not a very stringent test but you could try Apple diagnostics: https://support.apple.com/en-us/HT202731“
Tried this too (wasn’t aware of this startup routine, thanks) and the result was No Issues Found.

[Joe Marler] “This is especially troubling and could indicate some external commonality. E.g, a plug in, system config issue or an incipient hardware problem”
I have well over a hundred plug-ins from FXFactory, Coremelt, motionVFX and others. FXFactory enables easy disabling of their plug-ins and I tried this but the problem remained. I didn’t dare venture through the hoop-jumping that disabling the other plug-ins would require!

[Joe Marler] “Is all media on locally attached HFS+ or APFS drives, nothing on NTFS, ExFAT or NAS drives?”
Yes, all attached media drives are HFS. The system drive is APFS.

[Joe Marler] “You might check if any 3rd-party kernel extensions are installed by typing this command in terminal: kextstat | grep -v com.apple”
This was interesting, it pulled up 14x 3rd-party kexts. 11 of them could be accounted for but 3 were unfamiliar. I shall research these later and if they’re not related to any current hardware or app I’ll delete them.

I also tried logging in as another user with admin rights and the red line issue prevails.

The issue seems to be that FCPX is having a problem with clips rendered in Apple’s very own ProRes editing format in FCPX which is optimised for ProRes. It’s seemingly illogical. I shall try generating new lossless versions of problem clips and importing / optimising them into FCPX to see if this changes anything. But it’s not just imported clips that generate the red line, titles and transitions can also trigger it.

Another option in the process of elimination is to wipe the system drive, do a clean install of Mojave and migrate all apps etc from a CCC back-up. The random issues are just the best aren’t they!

I’ll report back with any new findings. Meanwhile, if you or anyone else have any other suggestions they are most welcome.

Thanks again!

Hamdani Milas

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com

[Hamdani Milas]

The red line issue gets weirder.

In another project timeline there are two lengthy clips from the same single source video, ProRes with 1920×873 dimensions for a widescreen appearance (used this workflow before with no issues). The first clip shows it’s rendered and there’s no red line above it. The second clip shows the red line above. (As does the animated title that follows) The second clip plays without issue.

If the second clip is selected and a Compound Clip is created from it the red line disappears and the clip renders.

If that Compound Clip is opened in its own timeline there is no red line above and the clip renders.

Oh! Maybe I spoke too soon. As I write this the first clip now has a red line above it. Right out of the blue! No action was carried out to trigger it. Random and unpredictable. And in this case the portion of the clip with the title above it stalls on playback while the audio continues to play. Following the title the remainder of the first clip plays okay.

Weirder and weirder.

Hamdani Milas

(Image has some clip names obscured for confidentiality.)

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com

[Joe Marler]

[Hamdani Milas] “The first clip shows it’s rendered and there’s no red line above it. The second clip shows the red line above. (As does the animated title that follows) The second clip plays without issue.”

Thanks for the additional info. To my knowledge, in FCPX there is no documented or even “known but undocumented” red line. It’s not like Premiere where green means rendered, yellow means non-rendered but GPU-accelerable, and red means non-rendered and non-accelerable.

In FCP 7 there were multi-color render bars with several colors for various render states. Red meant “render required”. That does not exist in FCPX unless it is some kind of legacy or debug code which was somehow triggered.

I was thinking back over this statement: “the project render routine itself is hit and miss, I usually disable background-render, now and then select all and manually trigger a render but portions of the timeline often refuse to render leaving the usual white dots.”

In general it should always render on command. Exceptions: Optical flow retiming can sometimes get stuck and it won’t render. If background rendering is left enabled sometimes render files can build up and render tracking gets confused. To avoid this keep background rendering disabled, manually delete all render files then do a one-time render with CMD+A to select all clips and CTRL+R to render. You can then selectively render additional clips or timeline ranges as needed.

Deleting render files using the FCPX UI does not delete analysis files, thumbnails, peak or waveform files. Unfortunately there is no documented way to delete those, but if you set library properties to store cache in a separate folder they will be placed in an .fcpcache bundle. You can safely delete the entire thing if needed.

There are also some render file tracking issues which can adversely interact with certain built-in and 3rd party effects. This can cause render files to become invalid and require re-rendering, even though no edits have occurred. There are other scenarios where render files will not be used even if they exist and are valid. Details: https://www.fcp.co/forum/4-final-cut-pro-x-fcpx/31621-help-losing-renders-after-fcpx-close-or-project-switch

That may sound bad but in general the FCPX render system works quite well.

It is possible the huge number of plugins and kernel extensions on your system could be a factor. Unfortunately there is no easy way to troubleshoot this. Booting MacOS in Safe Mode does not allow launching FCPX because OpenGL acceleration is disabled. Also there is no “FCPX safe mode” to boot with all plugins disabled.

All current FCPX plugins except for Motion templates run within the process address space of FCPX. This means any bug in any plugin can crash or destabilize FCPX. Supposedly this will be improved in the future as plugin vendors move their products to FxPlug 4 which can enable out-of-process plugins, thereby preventing a plugin bug from crashing FCPX: https://developer.apple.com/documentation/professional_video_applications/fxplug?changes=latest_minor&language=objc

All of the above notwithstanding, in general FCPX is overall quite reliable, especially from the standpoint of data integrity. I have managed post production of several very large documentary projects using FCPX, some involving 150 4k camera hours and 100 multi-camera interviews. We never lost any data or even a single edit, despite various periodic glitches and crashes. I only wish Premiere was that reliable the years I used it.

I don’t think there is an unsolvable problem with FCPX but there’s obviously an architectural issue regarding plugins and MacOS kernel extensions that can impact troubleshooting. This can make it quite cumbersome and time consuming to pursue. If you have another machine or can boot MacOS from a separate drive and do a clean provisional FCPX install without any plugins, that might be a path forward. I realize steps like that are aggravating and time consuming.

[Terry Barnum]

I found this on the fcp.co site from many years/versions ago talking about a red band above footage that doesn’t play well. There wasn’t a resolution unfortunately but the original poster did find a way to trigger it by compounding and getting rid of it by detaching the audio. Apparently the 7toX folks (now SendToX) called the red line a “corruption indicator.” https://www.fcp.co/forum/4-final-cut-pro-x-fcpx/6650-red-band-in-fcpx-timeline

-Terry

[Hamdani Milas]

Once again, thanks Joe for the detailed response and most helpful suggestions.

In 6 years of working almost full-time with FCPX I’ve learned its few quirks and glitches and have successfully run the usual routines to fix any unexpected behaviour. I’ve always marvelled at FCPX’s ability to save the very last editing action prior to now rare crashes and have never lost work. But this issue has got me completely flummoxed.

Prior to the macOS system update to Mojave and FCPX 10.4.8 everything was running smoothly and reliably. Maybe I should have known better! ☹

[Joe Marler] “Unfortunately there is no documented way to delete those, but if you set library properties to store cache in a separate folder they will be placed in an .fcpcache bundle. You can safely delete the entire thing if needed.”
Useful tip, thanks. I’ll try this, see if it makes a difference.

[Joe Marler] “There are other scenarios where render files will not be used even if they exist and are valid. Details: https://www.fcp.co/forum/4-final-cut-pro-x-fcpx/31621-help-losing-renders-a...”
Interesting thread, I’ve observed some of what’s described here with regard to un-rendered clips / effects. The final post in that thread from Joema is notable.

[Joe Marler] “If you have another machine or can boot MacOS from a separate drive and do a clean provisional FCPX install without any plugins, that might be a path forward. I realize steps like that are aggravating and time consuming.”
Agree this is an essential troubleshooting step. Neither my ancient MacBook Pro or Mac Pro are Mojave compatible but I’ll try installing FCPX on a Mojave boot drive, at least it will eliminate a plugin issue. I’ll also try to locate a machine with Mojave / FCPX 10.4.8.

I’ll continue to investigate this and will report back with any useful findings.

Thanks!

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com

[Hamdani Milas]

Thanks Terry for unearthing this most interesting thread. It seems quite similar to what I’ve been experiencing, except the red line is thicker!

I’ve also eliminated the red line by detaching audio along with a number of other steps including, as mentioned before, creating a Compound Clip from red-lined footage and also placing an identical version of the problem clip above it on the secondary storyline. I’ve also experienced that detaching the audio has no effect at all on the red line. These would seem to be clues pointing at some kind of rendering issue under the hood.

The appearance of the red line continues to be arbitrary, unpredictable and the investigation continues…

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com

[Hamdani Milas]

The random red line in the render bar continues to make its random appearances. I’m still at a loss as to a fix.

Sometimes the playback of the clip stutters beneath the red line, sometimes it doesn’t seem to affect playback at all. At worst playback will freeze on the first frame of a red-lined clip and this freeze will also be rendered on an exported mpeg4. That is a major concern.

The red line will sometimes have an obvious trigger like the application of colour-wheels or a plugin. Sometimes extending a clip will trigger it. Other times it just appears with no apparent trigger.

I have also discovered that a variety of seemingly unrelated ‘voodoo’ tricks can make the red line disappear; separating the audio, moving the clip to another primary storyline location, duplicating the clip and positioning it directly above, extending the clip by a few frames, going back to the browser and bringing the clip in again to replace the existing clip, turning visibility of a title clip above off or on, copying the entire timeline and pasting it into a new project and so on… Sometimes these moves eliminate the red line for good, replacing them with the regular grey dots, and sometimes they don’t.

It’s all quite illogical but I suspect it’s connected with the internal rendering pipeline because clips with the regular un-rendered grey dot indicators above do not always complete rendering even when they’re force rendered.

Tried a complete uninstall of FCPX by using AppCleaner and then a reinstall but that’s not a fix.

About the only thing I haven’t tried is a clean install of Mojave and copy/migrate all system drive files from a CCC backup. But that could only bring in pre-existing cruft and I’m very loathe to do a full reinstall of all apps and plugins because there are several hundred.

It’s also maybe notable that this issue doesn’t seem to have been reported elsewhere recently, possibly indicating a machine-specific hardware or software issue.

Regardless, it’s the kind of jinx that would be guaranteed to pop up when it’s least appreciated, on an urgent delivery…

I’ll leave it at this for now, if anyone has any suggestions they’ll be most welcome but I think this bizarre issue would have even the Apple FCXP team scratching their heads. If anyone on that team is reading this feel free to contact me and I’ll be happy to help trouble-shoot it.

Hamdani Milas

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com

[Joe Marler]

[Hamdani Milas] “The random red line in the render bar continues to make its random appearances. I’m still at a loss as to a fix.”

At this point we can only guess. There is no documented or “known but undocumented” red render bar.

If we assume it is related to the render system, we could examine that. Even if previously done, re-verify that that background rendering is disabled, and delete all cache files.

Inspect the location of the render folder. It should be external to the library. In Finder create a different folder on a different drive. Then use Finder CMD+I and under “sharing and permissions” grant “everyone” Read & Write access. Then press the gear icon and pick “apply to enclosed items”. After that use FCPX library inspector>Modify Settings>Cache to designate that folder. This is to ensure there’s no intermittent permissions or space issue. Make sure all drives are HFS+, not any ExFAT nor NTFS nor any on a NAS drive. A NAS is OK but not when troubleshooting an intractable problem.

Then manually render by selecting all clips in the timeline with CMD+A and render with CTRL+R. The freshly-generated render files should be placed in the new cache folder.

Examine the behavior. If it still happens, export your current project as an XML, create a new blank library, then load that project XML in that library. Render that timeline in the new library and examine the behavior. Using the XML route sometimes will filter out project corruption or anomalies.

[Hamdani Milas]

[Joe Marler] “If we assume it is related to the render system, we could examine that.”

Thanks for the suggestion Joe, I’ll try this and post results.

Hamdani

Independent producer, director, cinematographer, writer, editor
Milas Film Productions, Hong Kong
http://www.milasfilm.com