Face recognition questions, comparison to digikam


my use case is a small organisation, we have a lot of photos, it would be great to easily access photos of person XY.

I am thinking if I should use digicam (with face recognition) locally, or Nextcloud Photos with face recognition. Some questions about Nextcloud Photos:

  1. there are two different apps GitHub - matiasdelellis/facerecognition: Nextcloud app that implement a basic facial recognition system. and https://github.com/nextcloud/recognizewhat is the difference? Advantages/disadvantages?
    I only found this opinion AI and Photo's 2.0 - In-Depth Explanation of Nextcloud Recognize and How it Works - #5 by flow-axel which basically says facerecognize works better than recognize
  2. People/Faces cannot be manually assigned or corrected, right?
    Hot to manually tag persons?
    Manually Tagging Photos · Issue #168 · matiasdelellis/facerecognition · GitHub and
    Manual tagging when face not detected · Issue #611 · nextcloud/recognize · GitHub and
    Ability to create a new person. · Issue #603 · nextcloud/recognize · GitHub
    I think then these apps will not be useful for us, as I expect that the machine will not be perfect… as far as understand, digikam can do this.
  3. I read that it will recognize people from my address book. What is your experience with this feature? What if a cluster is assigned the wrong contact from my address book, or no contact at all?
  4. portability: Is the facial recognition data written into the file (as it is possible in digicam afaik) so that when the file moves, or is restored from a backup, the data is still there? What happens if I move the photo to external storage, is the face recognition data still available?

Btw thanks for the insightful/helpful articles How we got to the new Nextcloud Photos! - #6 by devnull and


Hi Alexander,

  1. facerecognition/recognize:what is the difference? Advantages/disadvantages?

facerecognition has been around longer, but of course only offers face recognition. Recognize may be easier to set up than facerecognition and possibly has better integration with the photos app. Face recognition results in recognize should be good, but some people seem to have issues. YMMV

  1. People/Faces cannot be manually assigned or corrected, right?
    Recognize allows assigning detected faces to a different person or unassigning it, but it’s not possible to tag undetected faces.

  2. I read that it will recognize people from my address book.

This feature in recognize was removed in recognize v3

  1. portability: Is the facial recognition data written into the file so that when the file moves, or is restored from a backup, the data is still there?

Recognize stores the faces in the db not in the file itself.

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@marcelklehr thank you. I actually thought integrating contacts from address book is super smart and useful.

Now I also found this explanation from the face recognition app, where a lot of users share their experience with both apps: Small disclaimer, announcement, or rather just want to share my concerns... · Issue #593 · matiasdelellis/facerecognition · GitHub
and there is also a technical comparison by the face recognition app developers here https://github.com/matiasdelellis/facerecognition/wiki/Face-Recognition-vs-Recognize

It will take me some time to digest all of this. But in the end, I cannot manually assign a person to a photo in either app, so neither app seems useful for my use case at the moment (that may change in the future).

Thanks anyway for the development of both apps :pray:

(For posterity: Note that the facerecognition vs recognize comparison was conducted OCt 2022. We have since improved face clustering in recent releases.)


Hi @marcelklehr.
I was trying to dive into Recognize but until now didn’t find the answer I was searching.
My question arise because I once configured my family photos folder (10 thousand photos) as a SMB external folder in my home docker NC. Now I switched to a local folder, mounted in docker. But it seems I loose previous faces recognized.
Is there a way to move them from a db to the new one?
And is possible to share the db to other users of NC?
Thanks in advance.

Hi @jobal – Welcome to this community! :slight_smile:

If you move the files outside of nextcloud recognize will not notice that it’s the same files, because nextcloud gives them new IDs. if you move them inside nextcloud, the files should retain their IDs and recognize should keep all the data around.
We haven’t worked on sharing recognized people at this point.

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Thank you for the welcome and the answer.
So, probably, disconnect SMB folder and mout the same as docker volume is the same as move files inside-outside-inside.