A method for radiometric calibration of color cameras using multispectral images

Abstract

The invention discloses a method for radiometric calibration of a color camera by using multispectral images, that is, solving the inverse camera response function and spectral sensitivity function of the color camera. The method includes the following steps: find the intrinsic linear relationship hidden between the pixels of the multispectral image, obtain the initial estimate of the inverse camera response function by recovering the intrinsic linear relationship from the color (RGB) image, and then use the existing data The spectral sensitivity function and the inverse camera response function coupled in the RGB image are solved alternately and iteratively. The invention uses the scene spectral information provided by the multi-spectral image, reduces the error caused by the inaccurate information used by the traditional method, improves the radiation calibration accuracy of the camera, and can obtain two calibration information of the inverse camera response function and the spectral sensitivity function at the same time .

Description

technical field [0001] The invention relates to the radiation calibration of the color camera, and can accurately obtain the inverse camera response function and spectral sensitivity function of the color camera under the condition of known scene multispectral image information. Background technique [0002] Obtaining accurate radiometric calibration information of color cameras is helpful for the implementation of many image processing algorithms, such as multispectral imaging, illumination estimation, color correction, etc. Since camera manufacturers usually do not provide this information, the camera inverse response function and spectral sensitivity function need to be estimated accurately. [0003] The camera response function converts the irradiance received by the camera sensor into the brightness of the image. In order to enhance the visual effect of the captured image, the camera response function is nonlinear in most cameras, and the role of the inverse camera res...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problems of the existing color camera radiometric calibration algorithm with low accuracy and limited application scenarios, and propose a method for color camera radiometric calibration using multispectral images, which can simultaneously obtain accurate camera inverse response functions and spectrally sensitive functions

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