	US 11,669,978 B2
	Method and device for estimating background motion of infrared image sequences and storage medium
Jihong Pei, Guangdong (CN); Kaiwen Liao, Guangdong (CN); Weixin Xie, Guangdong (CN); and Xuan Yang, Guangdong (CN)
Assigned to SHENZHEN UNIVERSITY, Guangdong (CN)
Appl. No. 17/278,972
Filed by Shenzhen University, Guangdong (CN)
PCT Filed Sep. 7, 2020, PCT No. PCT/CN2020/113690 § 371(c)(1), (2) Date Mar. 23, 2021, PCT Pub. No. WO2021/057455, PCT Pub. Date Apr. 1, 2021.
Claims priority of application No. 201910910191.8 (CN), filed on Sep. 25, 2019.
Prior Publication US 2021/0358133 A1, Nov. 18, 2021
Int. Cl. G06T 7/223 (2017.01); G06T 7/246 (2017.01)

CPC G06T 7/223 (2017.01) [G06T 7/248 (2017.01); G06T 2207/10016 (2013.01); G06T 2207/10048 (2013.01); G06T 2207/20021 (2013.01)]

8 Claims

1. A method for estimating background motion of infrared image sequences, comprising:

acquiring motion characteristics of a camera in a scene where the camera is located;

estimating a possible maximum displacement of a field of view of the camera in two adjacent frames of images of the infrared image sequences shot by the camera according to the motion characteristics;

determining regions to be matched of the two adjacent frames of images by using the maximum displacement, wherein the regions to be matched are the regions with the same background in the two adjacent frames of images;

dividing the regions to be matched into T sub-regions with same shape and size, and randomly generating M groups of sub-window set with the same shape in the T sub-regions of the region to be matched, wherein each group of sub-window set comprises K sub-windows, where T, K and M are positive integers, and K is greater than T; and each sub-window is entirely located in a sub-region, and each sub-region comprises at least one sub-window;

computing M background motion displacements of the two adjacent frames of images according to the M groups of sub-window set, through randomly sampling multi-window synchronous mutual information matching; and

determining the background motion displacement between the two adjacent frames of images in the image sequences by a potential function voting method according to the M background motion displacements;

wherein, randomly generating M groups of sub-window set in the T sub-regions of the region to be matched comprises:

acquiring parameters of each sub-region which comprise point coordinates of an upper left corner of the sub-region and height and width values of the sub-region, wherein the point coordinates of the upper left corner of the sub-region are determined based on a two-dimensional rectangular coordinate system established by taking an upper left corner of the region to be matched as an origin, an x-axis extending downward and a y-axis extending rightward;

acquiring the height and width values of the sub-windows in each sub-window set;

calculating the coordinates of the upper left corner of each sub-window using a random generation formula, according to the height and width value of each sub-window and parameters of a sub-region where the sub-window is located; and

obtaining the M groups of sub-window set according to the coordinates of the upper left corner of each sub-window and the height and width values of the sub-windows;

wherein the random generation formula is expressed as:

x_mk=Round(x_t+Uniform(0,1)*(H_x−h_x))

y_mk=Round(y_t+Uniform(0,1)*(H_y−h_y))

wherein x_mkis a coordinate of a k^thsub-window in an m^thgroup of sub-window set on the x-axis, and y_mkis a coordinate of the k^thsub-window in the m^thgroup of sub-window set on the y-axis, Uniform(0,1) is a function to uniformly distribute a random number in a random generation interval [0,1], Round (.) is a rounding function, x_tis a coordinate of an upper left corner of a t^thsub-region on the x-axis, y_tis a coordinate of the upper left corner of the t^thsub-region on the y-axis, H_xis a height value of the sub-region, H_yis a width value of the sub-region, h_xis a height value of the sub-window, and h_yis a width value of the sub-window.