Why Face unlock software not unlock the Device using Photos?

 Face unlocking software only work on scanning of real time Face of the Admin, It is because there are two base on which the Face unlocking software works, First it may scan the Face of Admin using camera which is much little secure than the Face scanner which work on the scanning of Face by using sensor in 3D mode which is highly secured and have no chance to be unlock device using photos because photos are not in 3D format due to which no one can get Accessed in the Device.

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