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Handling Video Import Problems in Lightroom Classic CC

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As of December 2018, Lightroom Classic CC frequently chokes on importing videos. To the extent that it took me 3 days of off-and-on work, a total of perhaps 4 hours of real, actual concentrated work, to import my collection of ~12,000 pictures and ~1,500 videos (with the videos randomly interspersed in the pictures).

The “nice” thing is that it was possible for me to import everything, despite having to kill Lr perhaps a hundred times. So, here’s what I did.

This was with Lr8 on Windows 10.

The Problem

It looks like the problem is actually with preview generating during the import. When you pick a folder in the import dialog, even before you start importing, it generates thumbnails/previews for you for all the pictures and videos in that folder. Unfortunately, it sucks pretty badly at the video part. In particular, there’s something called the dynamic link media server (no idea what it does) that has to process every video.

If you select for import a directory with video files in it, you’ll know you’ve hit this problem when the previews suddenly stop generating at a particular video; each preview should only take a few seconds to generate. (Sometimes the previews will be generated but not updated; try running your mouse over them, see if they show up.)

The Temporary Fix

As soon as stops making progress, stop the import (so you can maybe see which videos it got stuck on), close Lr, kill all Lr processes, kill all dynamic.* processes, kill Adobe Dynamic Link Manager.

Alternately just reboot.

Make sure video playback works on something you’ve already imported; don’t move on until it does. Note that you might have to bounce between different folders in Lightroom a couple of times for video playback to start working right after startup.

If it doesn’t work: Edit -> Preferences -> Performance ; turn on the video cache limit, hit purge purge, turn off video cache limit. (That last bit might not be necessary, not sure; regardless, once you’ve done all your importing, you should probably turn video cache limiting back on, as it will grow without bound otherwise, I’m told.)

If that still doesn’t work, turn off Lr and delete C:\Users\[you]\AppData\Local\Adobe\Lightroom\Caches\Video and reboot.

If that still doesn’t work, uh, good luck. :( That last step always worked for me.

How To Import Everything Else Quickly

To just get all your pictures imported so you don’t have to worry about them, leaving you with only video-related problems, you can go to C:FilesLightroom Classic CCand rename DynamicLinkMediaServer to any other name. That will 100% prevent all video imports, though, so you’ll want to rename it back when you’re done.

Small Files

Use Agent Ransack or another similar finder tool to find all movie files (i.e. *.mp4 , *.mov, whatever else you’ve got) that are smaller than 1024KiB. Move or delete all of them because as far as I can tell Lr is guaranteed to choke on a video file less than 2 seconds in length, and those files are probably crap anyway.

Large Folders

Lr appears to deal far, FAR better with fewer video files in a folder. I had sections of my import where the only thing I did was split up a large folder into many smaller sub-folders with 5 files each; I then imported the whole entire folder (same amount of files) that was getting stuck before and it worked (so weird!).

Fortunately, you don’t need to do it by hand.

You can use Folder Axe to split them up. Note that Folder Axe is abandonware, but it’s still on cnet and stuff and as of Dec 2018, works fine.

The smaller you’re willing to make the sub folders, the better; I found that “By Amount: 5” was very effective as I said.

Assuming you want the pictures to eventually end up back in the original large folder, do these steps:

When you split the folder up, before you import, move the split folders to another folder that is NOT inside the place you want the pictures to finally end up; Lr seems to sometimes have trouble with moving from a subfolder to the parent.

When you’re done with the import, select all the split folders, then ctrl-a to select all the pictures, then from the picture line at the bottom, drag to the folder you want them to end up in.

This takes A While; look at the Moving Files bar to see progress.

The Actual Import Process

  • Launch Lr
  • Check that video playback works; if not, see The Temporary Fix
  • Go to import
    • It may or may not help to set to Minimal previews.
  • Select a relatively small number of files; 500 files with less than 1/5th movies has been working for me. See Large Folders for how to deal with large folders.
  • WAIT until all the previews are generated! Make sure you look at all the previews to make sure. If preview generation gets stuck, import is guaranteed to fail.
  • If the previews generate smoothly for a while and then suddenly stop, and the first non-working item is a movie, Lr is choking on that movie. Right click on it and pick “Show in Explorer”; this will launch the folder. Right click on it and pick “Show in Explorer” again and it’ll select the actual specific file in question.
    • You can reset and retry, but you probably need to move/remove/transcode that movie.
    • I’ve been able to fix things by transcoding in Handbrake, at the risk of losing metadata(??). I’ve had some luck with the “Apple 720p30 Surround” preset.
    • I’ve also found sometimes videos can be read after I rename them, like by sticking “0-” at the front. This has, in particular, been necessary a few times after transcoding.
  • For a folder you’re having real trouble with, split it again; having 5 files per folder seemed to really help me for some reason, even if I actually did the import on the folder containing all the subfolders!
  • When a folder has been almost entirely imported, it’s sometimes better/easier to right-click on it from the main Library view and use “Synchronize Folder”.
  • Once all the previews generate successfully, which may take many launchings of Lr and file fixings, the import should work smoothly without any long waits. If the “Current Import” collection isn’t updating every second or so, it’s stuck, kill it.

Random Notes

Some steps I tried at various points that I don’t think help but who knows?, they might

C:\Users\[you]\Documents\Adobe – remove dynamiclinkserver

C:\Users\[you]\AppData\Roaming\Adobe – remove dynamiclinkmanager, dynamiclinkserver