# Mark Rectangles and Cell Rectangles

Some segmentation parameters reflect qualities with respect to different rectangles that surround each character. The OCRMax tool can take into consideration the dimensions of these rectangles during its segmentation process. Knowing the definition of these rectangles can help you determine the appropriate settings for these segmentation parameters.

For example, the following figure shows a set of dot-matrix characters:

The mark rectangle specifies the physical extents of a character in an (x, y) coordinate system. The following figure shows the mark rectangles for this string:

The cell rectangle provides information about the position of the mark rectangle with respect to the baseline, which is the line along the base of the character string. The following figure shows the cell rectangles for this string:

The cell rectangle can be used to discriminate characters that appear similar but have different sizes (such as the capital “O” versus a lower-case “o”) based on character sizes with respect to other character sizes in the string. In addition, a space character is defined only by its cell rectangle.