Non-uniform correction method for compensation of low-gray scale X-ray image signal

Abstract

The invention discloses a heterogeneous correction method for compensating low-grey scale X-ray image signals, comprising steps of, after training and obtaining reference data-training reference value compensating low-grey scale image signals based on analyzing draw bead generating reasons, firstly, carrying out normal heterogeneous correction to a collected article passing a channel type line scanning X-ray safety inspection device so as to primary image data; secondly, subtracting a training reference value of a scintillator at a corresponding position from a grey scale value of each scintillator in the primary image data to obtain a corrected image grey scale value; lastly, strengthening signals of an image of which the grey scale value is corrected by the heterogeneous stretching formula to make the corrected and strengthened image displayed more clearly. The inventive heterogeneous correction method for compensating low-grey scale X-ray image signals is characterized in that draw bead problem of low-grey scale images is solved, and penetration indexes and image quality of a X-ray safety inspection device are guaranteed.

Description

Technical field [0001] The invention relates to a correction method, in particular to a correction method for compensating low-gray X-ray image signals. Background technique [0002] In the online scanning X-ray security inspection equipment, the conventional non-uniformity correction method is usually used to correct the collected image signals, and the correction method uses the air background image signal as the correction reference image to digitally correct the collected items. For this correction method, the image signal can be corrected better when the collection item absorbs almost all the irradiated X-rays. However, when the collection item absorbs almost all the irradiated X-rays, for example, a thicker uniform Steel plate, the number of photons that X-rays hit the detection crystal after being absorbed by the thick steel plate is less, and at this time, because the photon fluctuation noise has little effect, the image signal-to-noise ratio is good, so the X-ray absorpt...

AI Technical Summary

Problems solved by technology

For this correction method, the image signal correction must be carried out better under the condition that the collected items absorb almost all the irradiated X-rays. Steel plate, the number of photons that X-rays hit the detection crystal after being absorbed by the thick steel plate is small, and at this time, due to the small influence of photon fluctuation noise, the signal-to-noise ratio of the image is good, so the absorption of X-rays by the detector crystal The weak inconsistency of the rectified image undergoes nonlinear stretching, thereby creating a drag phenomenon on the image

[0003] The problem of the above-mentioned steel plate image drawing (low grayscale image drawing) has always been an unsolved problem, which seriously affects the penetration index and image quality of X-ray security inspection equipment

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