To allow for a qualitative measurement of the biometric parameters from a video, we ask to meet the guidelines below. Parameters marked with 'required' must be met. Parameters marked with 'optional' are recommended, but not obligated.

The camera sensor is the part of the imaging system that is sensitive to light. The size of this sensor plays an important role in the final quality of the image or video. The larger the sensor, the more sensitive it is to light. Larger image sensors have larger pixels, which means less noise, better dynamic range and the ability to obtain more (subtle) information. The size of the sensor should be at least 5.0 mm in diagonal. The size of a pixel (unit cell) should be at least 1.0 μm.

Lens quality is becoming more important with the increasing pixel count on modern cameras. The resolution of digital photos is often limited by the camera lens rather than the resolution of the camera itself. In order to perform a qualitative measurement, the lens should have an aperture of at least f2.8 and be made from glass or an (optically) higher quality material.



The recording length of the video should be at least 15 seconds and should not exceed a length of one minute. A video length of 30 seconds is recommended.

The video frame rate should at least be 30 fps and should not exceed 60 fps. The recommended value is a recording frame rate of 30 fps.

The video resolution should be between 720p and 4K. We recommend a video resolution of 1080p.

Videos should be recorded using the commonly used H.264 codec (also referred to as MPEG-4).

When recording a video, you may have the option to provide some video encoding settings. One of those settings is the video bit rate. To make sure we don't loose valid pixel data during the video encoding process, we recommended to set the video bit rate to 8Mbps or slightly higher.