This is a confirmed regression and has been labeled as such.

Not adding a new issue, because I think this could be related. My movies are organized in a way
/Movie Title/File.ext
when I have multiple versions (e.g. DVD and Blu-Ray) then it's
/Movie Title/Movie Title - DVD.ext
/Movie Title/Movie Title - BD.ext
in some cases I also have
/Movie Title/Extras/Whatever special I have.ext

Up to 10.1.0 this ended up in one entry with the option to choose between DVD and BD version. Extras didn't show since switching from Emby to Jellyfin, but that's a different issue and I already raised #561 for this one.

With 10.2.0 I now have two entries for the movie plus one movie named "Extras". Would be great if this behavior could be reverted to what it was before.

It works for me

alashow: did you run a full library sescan asking to overwrite all metadata before you ended up with that, or did it do it on its own without any input from you? In the second case, my movie library is still fine and I also use a flat organisation, so I can't say that I can reproduce the bug. In the first case, I think it's related to something that I just posted on the jellyfin subreddit: https://www.reddit.com/r/jellyfin/comments/arjjsx/entry_identification_broken_in_1020/

That's strange indeed @cvium. I just created folders and some empty files to confirm the behavior

Then did a rescan of my movies and that's what my latest movies are supposed to be

I don't think that it matters, but just for completeness, I'm using the Docker image on Debian Linux

@iacchi the first scan was triggered automatically ("Enable real-time monitoring"). I tried rescanning with "Replace all metadata" option but it didn't help.

My movie media files strictly followed "flat movie organization" (one quality, {Movie} ({year}.{ext} + {Movie} ({year}.{lang}.srt) so it was easy to re-organize / group them with this little script:

#!/bin/bash

# move "Movie (year).mkv" files to respective "Movie (year)" folder
for full_filename in *mkv; do
  extension="${full_filename##*.}"
  filename="${full_filename%.*}"
  mkdir -p "$filename"
  mv "$full_filename" "$filename/$full_filename"
done

# move "Movie (year).mp4" files to respective "Movie (year)" folder
for full_filename in *mp4; do
  extension="${full_filename##*.}"
  filename="${full_filename%.*}"
  mkdir -p "$filename"
  mv "$full_filename" "$filename/$full_filename"
done

# move "Movie (year).avi" files to respective "Movie (year)" folder
for full_filename in *avi; do
  extension="${full_filename##*.}"
  filename="${full_filename%.*}"
  mkdir -p "$filename"
  mv "$full_filename" "$filename/$full_filename"
done

# move "Movie (year).eng.srt" files to respective "Movie (year)" folder
for full_filename in *eng.srt; do
  extension="${full_filename##*.}"
  filename="${full_filename%.eng.*}"
  mkdir -p "$filename"
  mv "$full_filename" "$filename/$full_filename"
done

# move "Movie (year).en.srt" files to respective "Movie (year)" folder
for full_filename in *en.srt; do
  extension="${full_filename##*.}"
  filename="${full_filename%.en.*}"
  mkdir -p "$filename"
  mv "$full_filename" "$filename/$full_filename"
done

@alashow if you can build yourself a test server, could you please try with #924 and report back? It might be a fix for your issue.

I don't know how to build the whole server. I use Docker container's provided in jellyfin/jellyfin.
Also, like I said above, I already re-organized my movie library to non-flat structure.

It should be easy enough to reproduce this error though?

I can confirm this is happening on my server. I have a folder named "Incoming" I drop my rips into to double check they encoded okay before I move them to the proper folders. After 10.2.0 they all come up as Incoming now. The only exception I've noticed is that a couple reprips I did, that I also dropped into the Incoming folder, did correctly identify, presumably because they already exist in the database in another folder.

OS: Ubuntu 18.04

#933 fixes the grouping behaviour again - at least for me

Tried the fix and it's still not matching some movies for me. About 75% of my library.
log_20190220 - Copy.log

Edit
I've noticed a bunch of errors like this in the logs

Killing ffmpeg process
[2019-02-20 22:37:00.515 -05:00] [ERR] ffmpeg image extraction failed for file:"T:\Movies\Captain America The Winter Soldier (2014).mkv"
[2019-02-20 22:37:00.515 -05:00] [ERR] I-frame image extraction failed, will attempt standard way. Input: "file:"T:\Movies\Captain America The Winter Soldier (2014).mkv""
System.Exception: ffmpeg image extraction failed for file:"T:\Movies\Captain America The Winter Soldier (2014).mkv"
at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.ExtractImageInternal(String inputPath, String container, MediaStream videoStream, Nullable1 imageStreamIndex, Nullable1 threedFormat, Nullable1 offset, Boolean useIFrame, CancellationToken cancellationToken) in C:\Users\mew\Desktop\jellyfin\MediaBrowser.MediaEncoding\Encoder\MediaEncoder.cs:line 730 at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.ExtractImage(String[] inputFiles, String container, MediaStream videoStream, Nullable1 imageStreamIndex, MediaProtocol protocol, Boolean isAudio, Nullable1 threedFormat, Nullable1 offset, CancellationToken cancellationToken) in C:\Users\mew\Desktop\jellyfin\MediaBrowser.MediaEncoding\Encoder\MediaEncoder.cs:line 588

@Evoley That looks like a different (media-related perhaps) bug - we've reverted all the code that touched this functionality since 10.1.0 in 10.2.1, can you test that out? IF that doesn't solve it let's open a new issue with that particular error.

@joshuaboniface Re-added the folder and It's still missing movies. Missed about 12 movies in total. I haven't gotten the error I posted above yet.

The errors you're experiencing seem unrelated to the original issue. Chapter and image extraction works for me. Maybe the metadata in your video files is bad.

Either way, please open a new issue.