4 results about "Homomorphic filtering" patented technology

U I T T R E K S E L Disclosed is a remote sensing image enhancement method and system based on homomorphic filtering topographic correction. The method includes: after acquiring a remote sensing image to be enhanced, converting the image from a red—green—blue (RGB) color space to a hue—saturation—value (HSV) color space, and extracting a brightness component; performing homomorphic filtering processing on the brightness component; combining’ the processed. brightness component with saturation and. hue, and. inverting the component back to the RGB color space to complete image enhancement; acquiring grayscale distribution of the enhanced image, and calculating image information entropy; further calculating contrast of the image through grayscale values of pixels; calculating an enhancement score of the image based on the information entropy' and. contrast, and. comparing' the enhancement score with a preset score to determine whether the image enhancement is completed. The present invention can effectively improve the image quality of remote sensing images. (+ Fig. 1)

The application discloses a method and system for detecting water stains and drug residues of a mask, and relates to the field of mask defect detection, and solves the problem of insufficient detection accuracy when detecting water stains and drug residues of a mask. The technical scheme is as follows: image data of the mask is collected; the image data is subjected to light calibration to obtain a brightness correction image; the brightness correction image is subjected to homomorphic filtering to compress the brightness range of the brightness correction image and enhance the contrast of the brightness correction image, thereby obtaining an enhanced image; the enhanced image is subjected to bilateral filtering to remove interference noise of the enhanced image and retain edge characteristic values of the enhanced image, thereby obtaining a result image; a preset AOI logic algorithm is used to perform defect determination on the result image, thereby obtaining a defect area in which water stains and drug residues may exist; and the defect area is subjected to defect re-inspection, and a defect detection result of water stains and drug residues is output.

The present invention belongs to the field of electronic countermeasure technology, and discloses a method, system for individual identification of communication radiation sources based on time-frequency filter coefficient fusion. The method includes: using a constant modulus algorithm in the time domain to perform equalization filtering on the transmitted signal carrying the radiation source fingerprint, extracting the equalizer coefficients after equalization convergence; converting the equalized, filtered signal to the frequency domain, applying a Mel filter bank to perform homomorphic filtering on the signal in the frequency domain to obtain the filtered Mel filter coefficients; performing frame-wise convolution on the equalizer coefficients, the Mel filter coefficients to fuse the time-domain, frequency-domain features of the communication radiation source, extract the communication radiation source fingerprint; constructing an individual identification model for communication radiation sources; identifying, classifying the extracted communication radiation source fingerprint features based on the individual identification model for communication radiation sources.