Method and system for cleaning images to highlight information recorded on a background surface

A method of cleaning an image of a background surface on which information has been recorded, said method comprising the steps of:

• for each pixel pij in said image:
• creating an array holding grayscale values of neighbor pixels within a region surrounding said pixel pij;
• calculating the average grayscale value of said neighbor pixels and thresholding said average grayscale value;
• comparing the grayscale value of the pixel pij with the thresholded average grayscale value;
• and
• retaining the pixel pij in said image if the grayscale value of said pixel differs from said thresholded average grayscale value, otherwise setting the value of the pixel pij to contrast pixels pij retained in said image.

A camera-based system for capturing an image of a target area comprising:

• a generally horizontally extending boom assembly, said boom assembly being positioned above a background surface;
• at least one digital camera mounted on said boom assembly at a location spaced from the plane of said background surface, said at least one digital camera being oriented so that the field of view thereof encompasses said background surface;
• and
• a controller in communication with said at least one digital camera, said controller receiving image data from said at least one digital camera and processing said image data to form a cleaned digital image of said background surface, during said cleaning said controller retaining only pixels representing information recorded on said background surface.