Thumbnails generated incorrectly

For help and support with Universal Media Server
Forum rules
Please make sure you follow the Problem Reporting Guidelines before posting if you want a reply
Post Reply
MediaNut86
Posts: 3
Joined: Wed Nov 24, 2021 9:42 am

Thumbnails generated incorrectly

Post by MediaNut86 »

Hello,

I've just installed UMS 10.13.0, on a Ubuntu 20.04 Desktop install and this is my first foray into getting this thing up and running.

So, I have managed to get it running and it is reading my small sample of movies/tv shows before I go all out and copy everything to the drive. The problem I am having is that the thumbnails are randomly wrong. Some generate correctly from the first 4 seconds of the video file while other are not only wrong... but they are from files that are in different folders 2 layers above or from adjacent folders. I have clears the cache, deleted the thumbs.db file(s), restarted the server, shutdown the server, rebooted the hardware and fiddled with the content settings. None of which seem to change the behavior, other than the effected videos change from broken to working and working ones are now broken.

The thumbs are fine in the web interface, but are broken on the Samsung TV. I had thought maybe it was the TV... but the old WD Mycloud (which this will hopefully replace) never had this issue.

Thanks in advance,

MN
User avatar
mik_s
Moderator
Posts: 511
Joined: Wed Aug 23, 2017 11:03 pm
Location: UK

Re: Thumbnails generated incorrectly

Post by mik_s »

My first thought is that your database is corrupt or the thumbnails were mixed up somehow when they were created. this can sometimes happen when upgrading to a newer version and something in the database does not update too, but since this is your first install I doubt that is it. I would suggest you quit UMS and delete the database for it to be recreates next time UMS starts, but I don't know the location of the database in linux. On windows it is in C:\ProgramData\UMS\database so look for a similar directory on your filesystem. It will contain the files medias.mv.db and medias.trace.db

For the web interface the thumbnails will be downloaded along with the metadata for that file so they will be different than the auto generated thumbnails stored in the local database.
Logs are important for us to help, Please follow This Link before asking for support. Just a forum cleaner, Will help if I can but no expert.
MediaNut86
Posts: 3
Joined: Wed Nov 24, 2021 9:42 am

Re: Thumbnails generated incorrectly

Post by MediaNut86 »

Thanks for the reply. The db files were found in the following.

/home/<username>/.config/UMS/database

Sadly, removing and rebuilding those files didn't help... some folders got even worse (didn't thing that was possible, lol).

The search continues.


MN
User avatar
mik_s
Moderator
Posts: 511
Joined: Wed Aug 23, 2017 11:03 pm
Location: UK

Re: Thumbnails generated incorrectly

Post by mik_s »

Could you post your logs? see the section in red above.
Logs are important for us to help, Please follow This Link before asking for support. Just a forum cleaner, Will help if I can but no expert.
MediaNut86
Posts: 3
Joined: Wed Nov 24, 2021 9:42 am

Re: Thumbnails generated incorrectly

Post by MediaNut86 »

Hello,

So, as any IT Pro with a computer collection habit... I installed UMS on a Win10 machine and got the same result as on the Ubuntu box.

Hopefully you can see something in the logs.

Thanks,

MN
Attachments
Win10_ums_dbg_2021-11-23-19-39.zip
(270.93 KiB) Downloaded 19 times
Ubuntu_ums_dbg_2021-11-23-19-44.zip
(109.21 KiB) Downloaded 20 times
User avatar
mik_s
Moderator
Posts: 511
Joined: Wed Aug 23, 2017 11:03 pm
Location: UK

Re: Thumbnails generated incorrectly

Post by mik_s »

I had a quick skim of your logs and could not see any obvious. There could be an issue with saving them to the database or maybe something wrong with the search queries. I don't know enough to be sure though.

One thing you could do is try an earlier version, deleting the database before installing and see if that works any better. If it does then there could be an issue in 10.13.0
Logs are important for us to help, Please follow This Link before asking for support. Just a forum cleaner, Will help if I can but no expert.
Nadahar
Posts: 1987
Joined: Tue Jun 09, 2015 5:57 pm

Re: Thumbnails generated incorrectly

Post by Nadahar »

I'd just like to add that usually, deleting the database is probably a very short-term solution. I'm pretty sure that the problem most of the time is because UMS doesn't have constant resource IDs, so that each time you restart UMS it will generate new resource IDs for all the media items. The UPnP AV standard doesn't mandate that the IDs are permanent, but "recommends" it. It seems like the makes of some of the renderers have "extended" the recommendation and expect it to always be true. This means that they tread the resource IDs as permanently identifying the same media, so they use the ID for all kind of caching or for remembering the playback position etc. This fails miserably when used with UMS where this logic is then "applied" to completely different media items, resulting in all kind of strange behavior like wrong thumbnails.

UMS assigns ID's sequentially from 1 in the order they are accessed each time it's restarted. This means that the low ID's will frequently be used for different media items and "collisions" will be frequent.
User avatar
SubJunk
Lead Developer
Posts: 3569
Joined: Sun May 27, 2012 4:12 pm

Re: Thumbnails generated incorrectly

Post by SubJunk »

It would be good to know whether this is a recent bug, can you please try some older versions? Maybe an earlier v10, or the last v9? Previous releases are at https://sourceforge.net/projects/unimediaserver/files/
It could theoretically happen before but it may be happening more often after a recent version so please help us figure that out
User avatar
SubJunk
Lead Developer
Posts: 3569
Joined: Sun May 27, 2012 4:12 pm

Re: Thumbnails generated incorrectly

Post by SubJunk »

I found a reference elsewhere in the forum to this bug happening since 10.10.1 so maybe try 10.10.0 https://sourceforge.net/projects/unimed ... s/10.10.0/
Post Reply