The application discloses a visual
water flow speed measurement method in a non-uniform
light field, comprising the following steps: S1, collecting video frames and converting the collected video frames into single-channel images; S2, performing
mask operation based on the single-channel images, shielding irrelevant background interference and extracting ROI; S3, performing smooth filtering on the images after the
mask operation and removing abnormal
noise points; S4, performing local
Gaussian threshold segmentation by using initial values to obtain binary images, wherein the initial parameters include neighborhood size and threshold bias; and S5, detecting feature points by using an ORB feature point detection
algorithm on the binary images. Through the local
Gaussian threshold segmentation technology, the threshold is dynamically calculated based on the local neighborhood gray scale characteristics of pixels instead of relying on a global fixed threshold, so that the non-uniform illumination space and time fluctuation caused by water
surface reflection, building shadow, weather change and the like are effectively offset, the core assumption of the brightness constancy of the
optical flow method is met, and tracking failure caused by the
distortion of the imaging features of the target is avoided.