Target tracking device and method as well as camera

The invention provides a target tracking device and method as well as a camera. The target tracking device is used for determining a target area, comprising the targets, in each follow-up image in an image sequence according to a predetermined target, comprising targets, in the initial image in the image sequence. The target tracking device comprises a first tracking component, a second tracking component and a weighting component, wherein the first tracking component is used for determining a first candidate target area in each follow-up image; the size of the first candidate target area is fixed for each follow-up image; the second tracking component is used for determining a second candidate target area in the follow-up image based on the first candidate target area in the follow-up image, and the second candidate target area adapts to the target in the follow-up image in shape or size; the weighting component is used for calculating the weight sum of the first candidate target area and the second candidate target area in the follow-up image and considering the weight sum as the target area of the follow-up image.