Face recognition has been one of the most requested digiKam features, and the latest version of the photo management application provides this functionality.
As the name suggests, the face recognition functionality can be used to find photos containing faces and attach face tags to persons in photos. This lets you quickly locate all photos of a specific person using digiKam filtering capabilities.
Tagging faces in digiKam is a rather straightforward procedure. Open the photo you want in the preview pane, press the Add a Face Tag button, draw a rectangle around a face on the photo, enter the face tag (e.g., the person’s name), and press Confirm.
Tagging faces manually can be a daunting proposition, especially if you have a considerable number of photos of people. Fortunately, digiKam can do the donkey job of automatically identifying faces for you. Expand the People sidebar, and press the Scan collections for faces button. In the Scanning Faces window tick the Detect and recognize faces check box. By default, digiKam scans all collections and tags, but you can limit the scan operation to certain albums and tags. To do this, press the Options button and select the albums and tags you want from the Search in drop-down list in the Albums section. While at it, you can tweak the face detection parameters in the Parameters section. Press then the Scan button and let digiKam do its job. Once the scan is completed, you should see all photos containing faces. You can then go through the scanned photos to fix face tags and remove incorrectly identified images.