Patent ID: 11893768
Assignee: CENTRAL SOUTH UNIVERSITY
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 1:
2. The method according to claim 1, wherein the step of vertex extraction is to sequentially perform wall thickness determination, pixel assignment, cell side length determination, and pixel annihilation,
the step of wall thickness determination being to set a square window whose side length is changeable from small to large, and, after a window having a certain side length traverses a morphological image, if the minimum value of the number of pixels having pixel values of 0 is non-zero, define the side length of the square window as a wall thickness L;
the step of pixel assignment being to set a square assignment window having a side length equal to the wall thickness L, traverse pixel points having pixel values of 1 in the morphological image with the assignment window, and assign a sum of the number of pixels having pixel values of 1 in the window to a pixel point at a center point of the assignment window;
the step of cell side length determination being to find a pixel point having the maximum assignment after the pixel assignment is completed, establish a square region having an initial side length E equal to the wall thickness L taking the pixel point as a center point, calculate an absolute difference Z between an assignment of each pixel point on each of four boundaries of the region and an assignment of the center point, traverse the whole morphological image, and record the minimum absolute difference Z and coordinates thereof; and establish a new square region with E=E+2 pixels, repeat the process until the minimum absolute difference Z has an obvious reverse increasing trend, and solve a honeycomb cell side length A through coordinates of a pixel point corresponding to the minimum absolute difference Z and coordinates of the center point of the region corresponding to the pixel point; and
the step of pixel annihilation being to find a pixel point having the maximum assignment, determine and record the pixel point as a vertex, establish a square window to be annihilated with the honeycomb cell side length A as a side length taking the pixel point as a center, clear assignments of all pixel points having pixel values of 1 in the window to be annihilated, further find a pixel point having the maximum assignment among the remaining assignments, determine and record the pixel point as a vertex, and repeat the operation of the window to be annihilated until the assignment of the pixel point having the pixel value of 1 is less than a preset threshold and then the vertex extraction ends.