Naming groups with Face Detection and Recognition

Applies to: Face Detection and Recognition

A very popular use of the Face Detection and Recognition technology is the auto-naming of group photos in NeoGroup.

How it works

Faces within the group photo are detected then cross-referenced against the portrait faces of subjects in the same job. When a match is found, the subject details (usually their name) are entered into the correct row and position of the name list.

The 'recognition' part of the process in NeoGroup, where the face in the group photo is recognized against a matching portrait image face, requires the portrait images to have already been detected.

For information on detecting portrait image faces, please refer to:

Detecting faces

Before you begin

As per the detection of portrait images, NeoGroup requires access to the original group images. The images should also be in their correct orientation.

Although faces in the group photograph can be detected at any time, the recognition step requires the portrait image faces to have already been detected.

Namimg the groups in Names Mode

With the above criteria having been met, naming the groups is then simply a matter of:

  1. Enter Names Mode (F6)
  2. Select one or more groups (it is recommended you start with a single group until familiar)
  3. From the menu select Names>Detect and recognize faces or use Ctrl-F5

The software scans the group image, detecting each face - indicated by a white box. Once the detection phase is complete, it recognizes the face in the group photo against the portrait image faces detected in the other application. When a successful match is made, the white box turns green and the name is placed into the correct row and position in the names list.

Figure 1: A group photo named by face detection and recognition.

Faces detected but not recognized

Ocassionally, faces in the group photo are detected but not recognized against a matching portrait image. In these cases the box around the face remains white and a yellow alert symbol alerts the user. These situations are almost always due to the subject in question not having a portrait image. In these cases the user can enter the name manually or use the lookup tool to find the subject.

Figure 2: Group photo where a face (the teacher) has been detected but not recognized.

In the screen grab above, the teacher's face was detected but since she was not photographed there is no corresponding portrait image for the software to match to. Note the yellow alert symbol against her row and against the group name itself.

Faces not detected

Very rarely, a face in the group photography may be detected at all. This is more likely with very large groups such as year level or whole school group photos where faces are very small and the camera resolution is not very high. In these cases it is possible to do a more sensitive face detection by invoking Shift-Ctrl-F5. This performs a deeper, more sensitive scan that has been found to always find faces irrespective of their size or the size of the group image.

Figure 3: A face not found in a large group photo.

In the screen grab above, the face in the back row, 2nd from left was not detected. Repeating the step with Shift-Ctrl-F5 detects the face.

The more sensitive Shift-Ctrl-F5 increases the likelihood of false faces (artefacts). It is therefore strongly recommended it is only used for the largest of groups

End of article