Image matching method for monitoring interior of pipeline based on nine-grid principle

The invention provides an image matching method for monitoring interior of a pipeline based on a nine-grid principle. The image matching method comprises the steps that: firstly, a system performs machine learning on a picture set of various conditions in the pipeline, wherein each human face image is sequentially subjected to gray scale conversion, normalization, image grid division, calculationof pixel feature values of each grid and embedment of feature values of each grid into one-dimensional nine-grid vector, and lightweight storage in a robot single-chip microcomputer is realized; and after a robot carries a camera and enters the pipeline, frames of collected videos are taken in real time, the frames of pictures are rapidly converted into one-dimensional nine-grid vectors, the similarity is calculated with the nine-grid vector set already stored in the single-chip microcomputer, and when the similarity is larger than a preset matching degree, the matching succeeds. According tothe image matching method,