TeX fonts in Adobe Type 1 (“PostScript”) format

Are you using “TeX fonts” in Adobe Type 1 format — such as:

• Computer Modern,
• AMS fonts, and
• extra “LaTeX” fonts (s.a. line, circle, symbol)?

You can find the above at the American Mathematical Society web site.

Ever wondered about their provenance?

It turns out that the Type 1 font files contain hidden “water marks” in the encrypted section.

Other fonts designed for TeX do as well, including:

• European Modern,
• Lucida Bright and Lucida New Math,
• Lucida Bright Expert,
• MathTıme and
• MathTıme Professional,

You can extract the water mark using a simple tool:

• Show_Water_Mark.exe (Windows application);
• Show_Water_Mark_CMD.exe (command line application); or
• Show_Water_Mark_CMD.c (C source).

Notes:

• In Windows, the font folder (default c:\windows\fonts) does not show the files in that folder, but something constructed from registry entries (it is a so-called “active” folder). To see the water marks of PFB files of fonts installed there, first copy them to another folder.
• The amount of information that can be hidden depends on the size of the font. As a result, some small fonts have incomplete water marks, while longer ones have repetitions.
• Commerical versions of the CM and AMS fonts will have different (later) watermarks.
• Recent revisions of some of the fonts may not have these watermarks because font modification software does not preserve such metadata.

Accessibility