ISO/IEC 39794-4:2019 pdf is free to download.Information technology — Extensible biometric data interchange formats — Part 4: Finger image data.
ISO/IEC 39794-4:2019 specifies:
— application specific requirements, recommendations, and best practices in data acquisition; and
— conformance test assertions and conformance test procedures applicable to this document.
ISO/IEC 39794-4:2019 is designed to accommodate both plain or rolled fingerprint images.Biometric systems perform better if the volar pad of the finger is centred both horizontally and vertically in the image capture area. Therefore, when capturing a fingerprint image, the centre of the fingerprint image should be located in the approximate centre of the image capture area.
ISO/IEC 39794-4:2019 is also designed to accommodate images from the palm of the hand or from the side of the hand opposite the thumb also known as the”writer’s palm” Most comparison subsystems perform better if the flat or fleshy part of the palm or writers palm is centred both horizontally and vertically in the image capture area. Therefore, when capturing a palmprint image, the centre of the palm or writer’s palm image area should be located in the approximate centre of the image capture area. The palm itselfmay be captured as one entity, or various pieces of it can be captured as single images.
