公开(公告)号：US11252320B2

公开(公告)日：2022-02-15

申请号：US17194611

申请日：2021-03-08

Applicant: Axis AB

Inventor： Johan Jeppsson ,  Björn Benderius ,  Niclas Svensson ,  Fritjof Jonsson ,  Jonas Levin ,  Stefan Lindgren

IPC: H04N5/232 ,  H04N7/18

Abstract: A method for determining whether a video camera is out-of-focus comprises: capturing image data; setting a focus setting difference threshold based on a filter function configured to filter the image data; adjusting a focus setting between a present focus setting and an altered focus setting such that a first subset of the image data is captured with the video camera being set in the present focus setting and such that a second subset of the image data is captured with the video camera being set in the altered focus setting, wherein the adjusting is performed such that a difference between the present and altered focus settings is below the threshold; forming the video stream by applying the filter function on the image data; determining first and second focus metrics of the image data; and determining whether the video camera is out-of-focus by comparing the first and second focus metrics.