Video Thumbnails Not Showing in Browser
I have Immich (server version 1.9.20) installed via TrueNAS Scale on a Lenovo T480 laptop (8 cores, 16GB RAM).
All thumbnails display fine when accessing the assets via the Immich app on my Android phone but when I access them via any browser (Firefox, Chrome, etc.) the don't display - instead, I get "Error loading image". Photo thumbnails display fine.
It's the same when I share assets in an album - the other parties get the same issue for video thumbnails.
The hover over preview works and the video plays if selected, so it seems it's just the thumbnails that don't render properly - see "Screenshot from 2025-08-27 09-26-45.png".
When I first installed Immich (several months ago) I had no such issues but it seems to have started during one of the Immich upgrades.
I've managed to find the following errors (see log file attached):
2025-08-21 15:31:56.385364+00:00[31m[Nest] 7 - [39m08/21/2025, 4:31:56 PM [31m ERROR[39m [33m[Microservices:{"id":"d43f284c-2b1b-4773-bedc-93c36742e89a"}][39m [31mUnable to run job handler (AssetGenerateThumbnails): Error: ffmpeg exited with code 234: Conversion failed!
I've not uploaded my docker-compose or env file on the basis that it's controlled by TrueNAS but please let me know if you do need it.
I've searched high and low for an answer to this and can't find anything, so I suspect that it's something out of whack with my setup, so any help would be much appreciated.
Many thanks
34 Replies
:wave: Hey @Alan,
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References
- Container Logs:
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Checklist
I have...
1. :ballot_box_with_check: verified I'm on the latest release(note that mobile app releases may take some time).
2. :ballot_box_with_check: read applicable release notes.
3. :ballot_box_with_check: reviewed the FAQs for known issues.
4. :ballot_box_with_check: reviewed Github for known issues.
5. :ballot_box_with_check: tried accessing Immich via local ip (without a custom reverse proxy).
6. :ballot_box_with_check: uploaded the relevant information (see below).
7. :ballot_box_with_check: tried an incognito window, disabled extensions, cleared mobile app cache, logged out and back in, different browsers, etc. as applicable
(an item can be marked as "complete" by reacting with the appropriate number)
Information
In order to be able to effectively help you, we need you to provide clear information to show what the problem is. The exact details needed vary per case, but here is a list of things to consider:
- Your docker-compose.yml and .env files.
- Logs from all the containers and their status (see above).
- All the troubleshooting steps you've tried so far.
- Any recent changes you've made to Immich or your system.
- Details about your system (both software/OS and hardware).
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- Any other information that you think might be relevant.
Please paste files and logs with proper code formatting, and especially avoid blurry screenshots.
Without the right information we can't work out what the problem is. Help us help you ;)
If this ticket can be closed you can use the /close command, and re-open it later if needed.I've run the job to regenerate thumbnails and uploaded the output of "docker logs" command as Immich_log2.txt.
Output of "docker ps -a":
=======
truenas_admin@truenas[~]$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
efcac7b79b00 ghcr.io/immich-app/immich-server:v1.139.4 "tini -- /bin/bash -…" 7 hours ago Up 7 hours (healthy) 2283/tcp, 0.0.0.0:30041->30041/tcp, :::30041->30041/tcp ix-immich-server-1
b5b035533d05 ghcr.io/immich-app/immich-machine-learning:v1.139.4 "tini -- python -m i…" 7 hours ago Up 7 hours (healthy) ix-immich-machine-learning-1
85ba4127779a ghcr.io/immich-app/postgres:15-vectorchord0.4.3-pgvectors0.2.0 "/usr/local/bin/immi…" 7 hours ago Up 7 hours (healthy) 5432/tcp ix-immich-pgvecto-1
fa7f301ccbce valkey/valkey:8.1.3 "docker-entrypoint.s…" 7 hours ago Up 7 hours (healthy) 6379/tcp ix-immich-redis-1
789a08e00ce7 python:3.13.0-slim-bookworm "python3 /script/run…" 7 hours ago Exited (0) 7 hours ago ix-immich-permissions-1
truenas_admin@truenas[~]$
=======
I can also confirm all the items on the checklist - I "reacted" to the numbers so hope that's how it's done?
Thanks
Are you using hw acceleration at all?
Nope
The weird thing is that it worked, perfectly when I first did the initial installs (TrueNAS Scale and Immich) and even went through a few Immich updates, but now, even after completely rebuilding the whole system (re-install of TrueNAS Scale and then Immich) it just won't render video thumbnails in a browser.
And just to repeat, all thumbnails (video and photos) render fine when viewed via the Immich Android app for the owner of the video
Not sure if this helps but the most obvious error I can find is this:
Error: ffmpeg exited with code 234: Conversion failed!
But I can't seem to find a solution online.
Several other people seem to have had that error too but there's either no solution offered or the solution doesn't work for me (e.g. for many, simply regenerating thumbnails works, but not for me).
I've also tried tweaking the thumbnail settings but to no avail.
It's only for video thumbnails this happens?
Yip
What version of immich? server version 1.9.20 isn't a valid immich version, latest is v1.139.4
Apologies, 1.9.20 must be some TrueNAS internal verison - the server version is 1.139.4 - see "Screenshot from 2025-08-27 18-23-07.png"
That screenshot is from the TrueNAS Scale Applications screen
Yeah you are on latest then. Any non sensitivie videos you can share to test on another instance? Otherwise I am not sure, I'm no expert when it comes to the library debugging stuff
Do you mean a video I can upload here for you to test?
I mean like share the actual video file to see if it works on another instance. Only if nothing sensitive obviously. But otherwise i am not sure what's going on. may need to wait for someone else to hop in
Sure, see VID_20250823_131435.mp4 - it's a video I took at my cousin's house a few days ago which is on my Immich instance and suffers the same symptom as all the other rest.
Huzzah, not jst you
Something else that may be worth noting is that there are some WhatsApp videos that were sent to me by a roofer and they generate thumbnails fine. They're of a much lower quality (and by that I mean there file size is much smaller), so not sure if that plays a part, but, again, these very same videos that generated thumbnails before are not generating thumbnails now
Also failed on my instance
mmmm ... so may be an Immich issue?
Possibly yes. Let me ask the team for any insight
Copy that
ffmpeg is not happy with "yuvj420p ... reserved" color space format of this video file, it seems.
I guess it does not prevent transcoding because only "fps" filter (used for thumbnails) is strict about color space.
Yes, that was the other error I saw in the logs and I've seen it addressed online in various forums but it involves tweaking the ffmpeg command, which, AFAIK, I can't do because Immich calls/runs it.
Is this then an Immich bug? Else how do I resolve it?
Somewhat similar issue https://github.com/UniversalMediaServer/UniversalMediaServer/issues/5242 links to https://fftrac-bg.ffmpeg.org/ticket/11020
Overall ffmpeg became more strict about track metadata/parameters. Therefore
- Most likely, track data is incorrect or not fully compliant with standards, so ffmpeg rejcts it when certain filters are applied (such as in Immich with "fps" for thumbnails). Then this should be fixed in camera software.
- Alternatively, this may be a ffmpeg bug / too strict handling.
Atm I'm not sure if it should be handled in Immich as it seems to be a corner case. But this may change in the future.
I'll have a quick look at code.
Many thanks Sergey
https://github.com/immich-app/immich/issues/20405
This is an upstream ffmpeg bug https://trac.ffmpeg.org/ticket/11020
[Issue] Some videos don't have previews (immich-app/immich#20405)
[Issue] Thumbnails are not created automatically, error when creating thumbnails manually (immich-app/immich#16154)
No, that video I shared is from my Android phone (Honor 200, which is roughly 18 months old)
Regarding the "Most likely, track data is incorrect or not fully compliant with standards, so ffmpeg rejcts it when certain filters are applied (such as in Immich with "fps" for thumbnails). Then this should be fixed in camera software" comment, I don't quite understand how the fault can lie with my phone considering it is bog standard, as are the photo & video settings? But if it is, is there anything I can change on my phone to resolve this issue? I've already tried tweaking various video settings on my phone, all to no avail:
- Changed resolution from 1080 to 720 (the lowest it can go)
- Changed fps from 30 to 60 (there are only these 2 options)
- Disabled location
I also tried changing the thumbnail quality from 60 to 40 in Immich but that also didn't help.
Because 'bog standard' doesn't mean much when every manufacterer has their own software team 😉
True, lol, but it is Android after all and I didn't think Honor would change it to the point where software like ffmpeg would consider it's videos as having invalid colour space?
No definitely not, as you can read from the bug Sergey linked it's a regression in ffmpeg
So what are my options? Wait for ffmpeg to fix it?
Realistically yes :<
Mmmm ... the ffmpeg bug's been open for months so I guess it's going to be a wait 😟
sad but true
Good if it's just a regression.
Bad if it's new expected behavior: enforcing strict check (and refusing even somewhat common "yuvj420p + reserved" from Android).
Btw, you can try older ffmpeg shipped from Debian
See if it helps generating thumbnails.