Some Useful Definitions

This section defines some terms and concepts used in this chapter.

accept threshold: If the matching score is below this level the character at the specified position fails verification.

arrangement: A sequence of character lines in space.

confidence threshold: If the difference between the matching score for the position and the highest scoring confusion character is greater than the confidence threshold, the position passes verification; otherwise, the verification status of the position is confused.

confusion score: A number in the range 0 through 1 that indicates the probability that two characters can be confused with one another during optical verification. A value of 0 means that the characters will never be confused with each other; and a value of 1 means that they will always be confused.

confusion threshold: If the computed confusion score for a character pairing is greater than the confusion threshold, the characters are easily confused with each other during optical verification.

degrees of freedom: A transformation type that changes the appearance of a character and can be characterized by a single numeric value.

matching score: The score generated when the OCVMax tool measures the match between the run-time character image for a position and the model image for a character expected to be in that position.

optical character verification (OCV): The process of verifying that the characters in a text area are the expected characters.

paragraph: A string or a set of strings containing characters using the same font.