3 results about "Otsu thresholding" patented technology

This invention discloses a machine vision-based method for measuring the trajectory of an electromagnetic needle selector. The method includes: acquiring a continuous image sequence of the needle selector during operation using a high-speed industrial camera; adaptively cropping the Region of Interest (ROI) using sparse optical flow fusion and image differencing; performing Otsu thresholding, connected component extraction, minimum bounding rectangle fitting, and gray-level centroid calculation on each needle selector region within the ROI to extract feature points of multiple needle selectors; constructing an inter-frame feature matching and trajectory reconstruction algorithm to continuously identify and sort the temporal trajectory of each needle selector; and finally outputting a complete and smooth multi-target motion trajectory. Compared to traditional single-point measurement methods, this method has advantages such as non-contact operation, high concurrency, and high precision, and is suitable for applications such as electromagnetic needle selector status assessment, fault detection, and performance analysis.

This invention discloses an image noise removal method and system based on AS-OCTA, relating to the field of medical image processing. The method includes the following steps: simulating eye movement using AS-OCTA to obtain a first image dataset with pure noise and a second image dataset without noise; inputting each image from the first image dataset into an improved Generative Adversarial Network (DCGAN) model to generate several third image datasets that approximate the first image datasets; fusing each image from the second image datasets with each image from the generated third image datasets and inputting the result into a residual U-Net neural network model to separate blood vessels from noise in the image data, thereby reconstructing a fourth image dataset; and binarizing each image from the fourth image dataset using the Otsu thresholding method to obtain a fifth image dataset. This invention solves the problem of scarce training datasets while improving the efficiency of noise removal.

This invention provides a method for geolocation accuracy analysis of medium-resolution satellite imagery, relating to the field of geolocation technology. The method includes: acquiring control point images and geographic location information corresponding to a ground truth image; acquiring a satellite imagery reference channel image and geographic location information; segmenting the satellite image using the Otsu thresholding method to obtain cloud and non-cloud area images; remapping the ground truth image using Gaussian filtering; extracting feature points from the cloud and non-cloud area images and the remapped image, and performing feature matching using the SIFT feature point matching algorithm; removing outlier matching point pairs using the RANSAC algorithm based on the matching point pairs; extracting the location information of precise matching point pairs based on the geographic location information of the ground truth image and the satellite image, and converting this information into positioning error; and verifying the positioning accuracy based on the positioning error to obtain the positioning accuracy verification result. This invention solves the technical problem that current positioning accuracy mainly depends on the coastline.