Patent ID: 6295371
Filing Date: 2001-09-25
Classification: G06T

Abstract:
A method for processing an image including text and continuous tone regions, the method comprising the steps of:performing a thresholding routine on the image to transform the image to a second image comprising components representing high contrast regions of the image;determining which components have connected black pixels to obtain a first group of components;determining which components have connected white pixels to obtain a second group of components;inverting one of the first and second groups of components to obtain a third group of components including both groups;determining a color of each component based on the image;determining a variance of color of each component;selecting a fourth group of components from the third group based on the determination of the variance of color whereby components having variance of color under a predetermined threshold are selected;calculating Hamming distances between scan lines of each component of the fourth group;calculating an average Hamming distance for each component of the fourth group;selecting a fifth group of components based on the average Hamming distances whereby components having an average Hamming distance under a predetermined threshold are selected;determining which components align with other components;selecting a sixth group of components from the fifth group based on the determination of alignment;classifying the components of the sixth group according to shape to obtain classes of components;identifying components of the sixth group belonging to a class of more than one component as text;identifying unidentified components of the sixth group that align with components of similar color as text;identifying unidentified components of the sixth group that align with the identified text as text; and,identifying unidentified components of the sixth group that are in close proximity to the identified text and relatively small in comparison to the identified text as text.