US 12,288,421 B2
Optical skin detection for face unlock
Peter Schillen, Ludwigshafen am Rhein (DE); Benjamin Guthier, Ludwigshafen am Rhein (DE); Friedrich Schick, Ludwigshafen am Rhein (DE); Manuel Guenther, Zurich (CH); Lars Diesselberg, Karlsruhe (DE); and Christian Lennartz, Ludwigshafen am Rhein (DE)
Assigned to TRINAMIX GMBH, Ludwigshafen Am Rhein (DE)
Filed by trinamiX GmbH, Ludwigshafen am Rhein (DE)
Filed on Jun. 14, 2024, as Appl. No. 18/743,640.
Application 18/743,640 is a continuation of application No. 18/468,352, filed on Sep. 15, 2023.
Application 18/468,352 is a continuation of application No. 18/264,326, previously published as PCT/EP2022/053941, filed on Feb. 17, 2022.
Claims priority of application No. 21157800 (EP), filed on Feb. 18, 2021.
Prior Publication US 2024/0331450 A1, Oct. 3, 2024
Int. Cl. G06V 40/40 (2022.01); G01S 17/894 (2020.01); G06F 21/32 (2013.01); G06T 7/50 (2017.01); G06V 10/141 (2022.01); G06V 10/145 (2022.01); G06V 10/25 (2022.01); G06V 10/54 (2022.01); G06V 10/60 (2022.01); G06V 10/764 (2022.01); G06V 10/82 (2022.01); G06V 40/16 (2022.01)
CPC G06V 40/40 (2022.01) [G01S 17/894 (2020.01); G06F 21/32 (2013.01); G06T 7/50 (2017.01); G06V 10/141 (2022.01); G06V 10/145 (2022.01); G06V 10/25 (2022.01); G06V 10/54 (2022.01); G06V 10/60 (2022.01); G06V 10/764 (2022.01); G06V 10/82 (2022.01); G06V 40/165 (2022.01); G06V 40/168 (2022.01); G06V 40/172 (2022.01); G06T 2207/30201 (2013.01)] 29 Claims
OG exemplary drawing
 
1. A method for face authentication comprising the following steps:
a) at least one skin detection step, wherein the skin detection step comprises projecting at least one illumination pattern comprising a plurality of illumination features on the scene by using at least one illumination unit and determining at least one second image using the at least one camera, wherein the second image comprises a plurality of reflection features generated by the scene in response to illumination by the illumination features, wherein the skin detection step comprises determining at least one material property of the reflection features by using the processing unit, wherein a detected face is characterized as skin if the material property corresponds to at least one property characteristic for skin, wherein the illumination pattern is selected from the group consisting of at least one point pattern, at least one line pattern, at least one stripe pattern, at least one checkerboard pattern, and at least one pattern comprising an arrangement of periodic or non-periodic features;
b) at least one 3D detection step, wherein the 3D detection step comprises determining at least one depth level from the reflection features of the second image, wherein the detected face is characterized as 3D object if the depth level deviates from a pre-determined or pre-defined depth level, wherein the 3D detection step comprises determining depth information of the reflection features by structured light; and
c) at least one authentication step, wherein the authentication step comprises authenticating the detected face by using at least one authentication unit if in step a) the detected face is characterized as skin and in step b) the detected face is characterized as 3D object.