Morphological Automatic Landolt C Orientation Detection

摘要

A method and apparatus are provided for automatically assessing a resolution of an optical sensor. An image is obtained from the sensor. The obtained image is thresholded to generate a binary image of black and white pixels using a first threshold value. A target area is selected from the binary image. The first threshold value is increased to generate a second threshold value. The target is thresholded using the second threshold value. At least one pixel is tagged at a center of the target area. Pixels surrounding a tagged pixel are processed, tagging white pixels. If a tagged pixel is at an edge of the target area, an orientation of an object in the target area is determined based on that edge. And, if no pixel is tagged at the edge of the target area, the second threshold value is decreased and the thresholding, tagging, and processing steps are repeated.

主权项

1. A method of assessing a resolution of an optical sensor, the method comprising:
obtaining an image from the optical sensor; thresholding the obtained image to generate a binary image of pixels having contrasting colors using a first threshold value; selecting a target area from the binary image; increasing the first threshold value to generate a second threshold value; thresholding the selected target area using the second threshold value; tagging at least one pixel at a center of the selected target area; processing pixels surrounding a tagged pixel, tagging those pixels that are a lighter color of the contrasting colors; in response to a tagged pixel being at an edge of the selected target area, determining an orientation of an object in the selected target area based on the edge of the selected target area; and in response to not tagging a pixel at the edge of the selected target area, decreasing the second threshold value and repeating the thresholding, tagging, and processing steps.