Font Identification in Digital Document for Per-Face Hint Control

Abstract

Conventional outline fonts are designed to store a self-standing routine for a specified glyph, because they are designed for small character sets without duplicated glyphic components, like Latin, Greek and Cyrillic scripts. The ratio of the numbers of the glyphs and glyphic components are almost comparable. But in the case of CJK Ideographs, the number of the glyphic components is remarkably smaller than the size of the character set. Thus, modern outline fonts provide the composite glyph mechanism which composes a glyph by referring the subroutines for the glyphic components. To reduce the number of the glyphic component subroutines, some fonts use TrueType hinting instruction to stretch or compress the components. Such fonts have no flexibilities for the applications of the TrueType hinting. In this report, the several methods how to detect such fonts are discussed and the benchmark of the proposed methods in the document rendering process is reported.