Accurate calibration method of image surface of optical camera

Abstract

The invention relates to an accurate calibration method image surface of optical camera. The method is as follows: fixing a calibration target with constant brightness at a screen center of a displayscreen; the camera is fixed on the tripod head, the calibration target is lightened so that the image formed on the effective field of view of the camera is a light spot; rotating the camera accordingto a preset angle step by a tripod head control camera, collecting the intensity data of the spot each time and recording the corresponding camera pitch angle and the azimuth data so as to obtain theeffective field-of-view brightness surface of the camera; and compensating the curved surface to obtain the effective field-of-view brightness plane after the camera calibration. The invention solvesthe problem of accurate calibration of the effective field-of-view image surface of the optical camera, has the advantages of simple method and low cost, breaks the technical bottleneck of the calibration of the effective field-of-view image surface of the optical camera, can finish the optical plane calibration of the application of the large-field-of-view engineering application and has high application value.

Description

technical field [0001] The invention belongs to the technical field of acquisition and correction of LED display screens, and relates to a method for accurately demarcating curved surfaces of images acquired by an optical camera. Background technique [0002] With the rapid development of the LED display field, the application requirements of the LED display screen are also emerging, and the display effect of the LED display screen has become one of the important factors restricting the development of the LED display field. Due to the discreteness and attenuation of light-emitting diodes, the LED display has the problem of uneven brightness display, which seriously affects the display effect. In order to overcome this problem, the point-by-point brightness correction technology of LED display screens emerged at the historic moment, and developed rapidly, which greatly improved the display quality. [0003] At present, the LED point-by-point correction technology that is mai...

AI Technical Summary

Problems solved by technology

However, the industrial camera or SLR camera used for calibration is not a standard luminance measurement instrument and has not been strictly calibrated. Therefore, during the image acquisition process, due to factors such as lens distortion and camera vignetting, there are serious curved surfaces in the acquired image. Phenomenon, which greatly affects the display effect after correction

[0004] In order to solve the above problems, although the uniform field calibration method mainly used at present can effectively correct the acquisition surface of the camera, the manufacturing of the uniform field is difficult and expensive, which is not conducive to engineering applications; while other methods cannot correct the surface well

Therefore, the camera acquisition surface becomes a difficult problem of acquisition correction

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