A Method of Relative Radiation Correction for CCD Image

Abstract

The invention provides a method for performing relative radiation correction on CCD images, performing relative radiation correction on the original image obtained by push-brooming of a one-dimensional CCD camera, including: step A, using the integrating sphere method to test the detection units of the one-dimensional CCD camera The radiation calibration data under different integrating sphere output radiance Lj and different integration time Tk step B, the radiation calibration data of each detection unit of the one-dimensional CCD camera under different energy levels Lj and different integration time Tk are used for the improved relative radiation correction Model, calculating the relative radiation correction coefficient of each detection unit; and step C, for each pixel in the original image, using the relative radiation correction coefficient of the detection unit corresponding to the pixel to perform radiation intensity correction, and then obtaining a relative radiation corrected image. The invention avoids the problem of obvious color difference in spliced ​​images inside the same flight zone and adjacent flight belts due to the difference in integration time when processing the aviation linear array CCD image.

Description

Technical field [0001] The present invention relates to the field of remote sensing technology, in particular to a method for performing relative radiation correction on CCD images. Background technique [0002] One of the core components of the aviation optical linear array load is the CCD (Charge-coupled Device) array, which contains many detection units. Due to the limitation of the manufacturing process, the parameters of each detection unit cannot be guaranteed to be consistent, resulting in certain differences in the response characteristics of each detection unit of the CCD array. For the push-broom sensor, the remote sensing image is pushed and scanned by the linear CCD array. Due to the difference in the response characteristics of the detection units of the CCD array, the final image will have uneven brightness in the entire field of view, or even Exhibits band noise. [0003] The radiation correction of optical remote sensing images includes relative radiation correcti...

AI Technical Summary

Problems solved by technology

Even under the same incident radiation conditions, the DN value output by the CCD camera will be different due to the difference in the integration time of the CCD camera

If the relative radiation correction method shown in Figure 1 is still used to perform radiation correction on the aero-optical linear array load image, the DN values ​​of the images acquired at different integration times after relative radiation correction will not be on the same benchmark, which makes the use of There will be obvious chromatic aberration when the corrected adjacent air strip images are stitched together, which will affect the stitching effect

At the same time, due to the dynamic change of the integration time, the images of the same ground object scene in the adjacent flight zone have different DN value outputs, so that it is impossible to use the unified absolute radiometric calibration coefficient to perform absolute radiometric correction on the image, which will give the subsequent absolute radiometric correction band come with great difficulty

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