Unfolding method for restoration of fisheye image

Abstract

The invention provides an unfolding method for restoration of a fisheye image, and relates to the restoration and correction of a fisheye image based on the equidistant projection principle of a spherical model. The method comprises the following steps of: establishing a spherical imaging model, consistent with the equidistant projection principle, of the fisheye image(including the establishment of a fisheye image coordinate system and a camera coordinate system); establishing an unfolded window coordinate system and an unfolded image coordinate system, and calculating the relationship between the two coordinate systems; establishing the relationship between the unfolded image coordinate system and the camera coordinate system; calculating the relationship between the unfolded image coordinate system and the fisheye image coordinate system; and finally obtaining a whole image unfolded in any specified direction. The method can overcome the defect of the methods that can unfold only the top part information of fisheye lenses and can not only restore the top part information, but also restore all information in any direction, The method can be applied to the equidistant projection principle based fisheye lenses as well as other projection principle based fisheye lenses, so that the method has a wide application prospect in fields of image tracking, monitoring, video conference and the like.

Description

【Technical field】: The invention relates to the restoration and correction of a fisheye image based on the equidistant projection principle of a spherical model, and image expansion with any incident light of a fisheye lens as an optical axis, belonging to the technical field of image processing. 【Background technique】: Omni-directional vision refers to a single image taken by a camera equipped with a super wide-angle fisheye lens placed vertically upwards, which can record all scenes in a 360° azimuth perspective, that is, the scenery in the entire area around the front, back, left, and right "at a glance" Read it all". The acquisition of this "panoramic image" does not require the mechanical rotation of a single camera for "panning", or the use of multiple cameras to capture multiple images at the same time for "pasting", thus simplifying the system structure and processing procedures, which is beneficial to machine vision applications real-time requirements. It has spec...

AI Technical Summary

Problems solved by technology

Due to the special design of the fisheye camera, the shorter the focal length, the larger the angle of view; the larger the angle of view, the stronger the deformation caused by the optical principle. The image captured by the fisheye lens remains unchanged except for the scene in the center of the screen, and other things that should be The horizontal or vertical scene has changed accordingly, so the omnidirectional image obtained by the fisheye camera is seriously distorted

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