Under the low illumination environment

using the Ultraviolet imager to detect high-voltage equipment external corona discharge

the output image is blurred and affects the location

analysis and recognition of discharge fault

so it is necessary to take certain image processing algorithm to improve the image quality.After a brief analysis of the characteristics of this type of ultraviolet images

the method of image enhancement with filtering and gray level transformation is proposed in this paper.The de-noising effect of spatial filtering

frequency domain filtering and wavelet de-noising is compared and analysis

then by using segmentation gray scale linear transform and adaptive histogram equalization algorithm

the image brightness and contrast is improved.Through practical engineering application

the effectiveness of this method has been verified.