Methods and Systems for Detecting Numerals in a Digital Image

A method for detecting a numeral connected component in a digital image, said method comprising:

• a) receiving a text-line component, wherein said text-line component comprises a plurality of connected components in a digital image;
• b) determining a component bounding box for each of said plurality of connected components, wherein each component bounding box comprises a first-side coordinate, a second-side coordinate, a third-side coordinate and a fourth-side coordinate, wherein said first-side coordinate and said second-side coordinate are associated with a first axis of said bounding box and said third-side coordinate and said fourth-side coordinate are associated with a second axis of said bounding box;
• c) determining a first variability measure associated with said first-side coordinates;
• d) determining a second variability measure associated with said second-side coordinates;
• e) determining a third variability measure associated with said third-side coordinates;
• f) determining a fourth variability measure associated with said fourth-side coordinates;
• g) determining a first accumulation of said first variability measure and said second variability measure;
• h) determining a second accumulation of said third variability measure and said fourth variability measure;
• and
• i) when said first accumulation and said second accumulation meet a first criterion:
• i) classifying said text-line component as a numeral component when said first variability measure meets a first threshold criterion and said second variability measure meets a second threshold criterion;
• and
• ii) classifying said text-line component as a non-numeral component when either said first variability measure does not meet said first threshold criterion or said second variability measure does not meet said second threshold criterion;
• and
• j) when said first accumulation and said second accumulation do not meet said first criterion:
• i) classifying said text-line component as a numeral component when said third variability measure meets a third threshold criterion and said fourth variability measure meets a fourth threshold criterion;
• and
• ii) classifying said text-line component as a non-numeral component when either said third variability measure does not meet said third threshold criterion or said fourth variability measure does not meet said fourth threshold criterion.