公开(公告)号：US10075642B2

公开(公告)日：2018-09-11

申请号：US15049952

申请日：2016-02-22

Applicant: AXIS AB

Inventor： Jonas Hjelmström ,  Andreas Nilsson

IPC: H04N5/232

CPC classification number: H04N5/23287 ,  H04N5/23212 ,  H04N5/23254 ,  H04N5/23258 ,  H04N5/23267

Abstract: In a method for image stabilization a number of operations are performed to stabilize an image and to output a focal length value. The steps include capturing video by means of a video camera with unknown focal length running an image stabilization process operating on an input from a hardware detector detecting the displacement of the camera and on an adjustable focal length value. Inter-image displacement is corrected based on the input from the hardware detector and the adjustable focal length value. By evaluating the displacement and adjusting the focal length value until a satisfactory image stabilization is achieved a value of the focal length may be output.

公开(公告)号：US09888187B2

公开(公告)日：2018-02-06

申请号：US15088787

申请日：2016-04-01

Applicant: Axis AB

Inventor： Jonas Hjelmström ,  Andreas Nilsson

IPC: H04N5/262 ,  G06T5/00 ,  H04N5/357 ,  H04N17/00 ,  G06T3/00 ,  H04N5/217 ,  G06T7/80 ,  G06T7/13

CPC classification number: H04N5/2628 ,  G06T3/0093 ,  G06T5/006 ,  G06T7/13 ,  G06T7/80 ,  H04N5/217 ,  H04N5/3572 ,  H04N17/002

Abstract: A method and apparatus for determining a focal-length setting of a lens mounted to a camera is disclosed. In a method for determining a focal-length of a lens mounted to a camera, a distorted image of a scene is captured. A distortion-correction function is applied on the distorted image or on a portion of the distorted image. A most representative distortion-correction function is identified and a current focal-length setting for the lens is identified by correlating the identification to a data compilation.