Duplicate faces of the same person found on photos

[kuzmos]

🐛 Bug Report

• [] 📁 I've Included a ZIP file containing my librephotos log files - no errors as such
• ❌ I have looked for similar issues (including closed ones)
• 🎬 (If applicable) I've provided pictures or links to videos that clearly demonstrate the issue

📝 Description of issue:

When I run Face scan over my library of 150k photos after recent updates, duplicate faces (often in a bit different positions) started appearing in abundance on the photos with those faces already marked. On the previous scans, the confidence was not too low, ie mostly correct persons were suggested, so I've clicked through and went on. However after a recent photo scan, around 5k new faces appeared, and from random clicking they are mostly just duplicates of faces already marked, and the confidence is probably very low, as no person is suggested in Details tab, and nothing is ever displayed in Inferred, no matter how I play with selectors.

See the screenshot of Details for illustration. Two persons are already marked in the photo, but the new scan found those faces in a slightly different area, and failed to infer.

🔁 How can we reproduce it:

If a scanning faces algorithm has changed, then it MAY BE caused by first scanning on the previous versions (I have my library for a couple of years now), label faces, then re-scan with the latest version, and faces appear anew, along with the already labeled ones.

Please provide additional information:

• 💻 Operating system:
  Ubuntu 24 VM
• ⚙ Architecture (x86 or ARM):
  x86
• 🔢 Librephotos version:
  latest dev
• 📸 Librephotos installation method (Docker, Kubernetes, .deb, etc.):
  docker
  • 🐋 If Docker or Kubernets, provide docker-compose image tag:
    dev
• 📁 How is you picture library mounted (Local file system (Type), NFS, SMB, etc.):
  smb
• ☁ If you are virtualizing librephotos, Virtualization platform (Proxmox, Xen, HyperV, etc.):
  TrueNAS Scale
  

[kuzmos]

The easiest way to avoid this would be to skip marking the person's face on the photo, if the person is already there. Logically, one person cannot appear on the photo twice. This would eliminate the duplications (or triplications or even more - I have multiple copies of the same person on a single photo very often now).

[derneuere]

Some users create collages with multiple photos of the same person using other software. We perform a technical check to determine if the new region is similar to an existing one. If it is, a new face should not be created.

It would be very helpful if you could provide a reproducible example. Specifically, if you have a file where switching between face models results in multiple models being generated, please share it with us.

[kuzmos]

It's happening on my user with the largest collection, around 150k photos. I'll try to copy some of photos to the new user and run several scans. I'm a bit reluctant to share the photos with undistorted faces tbh, would that be sufficient for you to debug?