US 12,307,622 B2
Method and device for dewarping a region of a fisheye view image
Ludvig Pettersson, Lund (SE); Jiandan Chen, Lund (SE); and Hanna Björgvinsdóttir, Lund (SE)
Assigned to AXIS AB, Lund (SE)
Filed by Axis AB, Lund (SE)
Filed on Jun. 8, 2022, as Appl. No. 17/835,254.
Claims priority of application No. 21178765 (EP), filed on Jun. 10, 2021.
Prior Publication US 2022/0398687 A1, Dec. 15, 2022
Int. Cl. G06T 3/047 (2024.01); G06T 3/18 (2024.01)
CPC G06T 3/047 (2024.01) [G06T 3/18 (2024.01)] 13 Claims
OG exemplary drawing
 
1. A computer implemented method for dewarping a region of a fisheye view image, wherein the fisheye view image is captured by a fisheye lens camera and comprises a first dewarping pole, DP1, the method comprising:
defining a region of interest, ROI, within the fisheye view image;
determining a center, G, of the ROI;
defining a temporary annulus sector region of the fisheye view image such that the temporary annulus sector region comprises the ROI, and such that the temporary annulus sector region has its center at DP1 and has a temporary outer arc shaped edge and a temporary inner arc shaped edge;
defining a second dewarping pole, DP2, in the fisheye view image at a dewarping pole moving distance, D, from DP1 along a radial direction extending from G of the ROI through the DP1, wherein the radial direction is further directed such that DP1 is located between DP2 and G;
setting a dewarping annulus sector region of the fisheye view image such that the dewarping annulus sector region comprises the ROI, and such that the dewarping annulus sector region has its center at DP2 and has its dewarping inner arc shaped edge maintained at a same radial distance, along the radial direction extending from G of the ROI through the DP1, from DP1 as the temporary inner arc shaped edge; and
dewarping the dewarping annulus sector region of the fisheye view image.