FFMERGE Theory of Operation
FFMERGE comprises special Windows fax drivers and a True-type font. Using the special font you can embed fax number, email address and/or other information in a Windows graphical format. The FFMERGE driver can quickly and efficiently recover this embedded data, after the document has been rasterized by Windows. The fax number and other data can then be used to control the transmission of the fax or the disposition of the fax-format document.
The information to be processed in this way must be a line of text in the special FFMERGE font, in black 12-point size, and must be the first non-white line on the first page of each document. This line should be in the top one inch of the page. All the text in the line, including spaces, must be in the FFMERGE font. The line is stripped from the document by the driver, so will not be seen by the recipient of the document. In the remainder of this document, we refer to this text line as "the action line". Enlarged, the action line looks like this:
The bar above and below, and the 'speckle' above the characters in the action line, allow the FFMERGE driver reliably to determine the contents of the action line by reference to only a few scan lines at the top of the page as it is rasterized. This is what gives FFMERGE its unique speed and simplicity.