Handling control characters and overstrike with backspace

[BobLd]

The following document contains several control characters. For example, the page 8 contains \u0002, \u0003, \b, \u0005, \u0006, \a, \t, \n, \v, \f. The problem with some of the control chars listed above is that their bounding boxes create issues with words, lines and textblocks. I guess they should be removed from the page's letters (appart from the backspace, see below).

The backspace character (\b) is used in this page to overstrike the = sign and transform it into an ≠ (equal sign with a strikethrough). This backspace behaviore should be handled to return the correct character.