Fax printers. One of the advantages of inkjet printing is that inkjets can affordably print in color; therefore, many of the inkjet-based fax machines claim to have color fax capability. There is a standard called ITU-T30e (formally ITU-T Recommendation T.30 Annex E ) for faxing in color; however, it is not widely supported, so many of the color fax machines can only fax in color to machines from the same manufacturer. Stroke speed in facsimile systems is the rate at which a fixed line perpendicular to the direction of scanning is crossed in one direction by a scanning or recording spot.
Black fax Black fax The term black fax refers to a prank fax transmission, consisting of one or more pages entirely filled with a uniform black tone. The sender's intention is generally to use up as much of the recipient's fax ink, toner, or thermal paper as possible, thus costing the recipient money and/or denying the recipient use of their own machine (this is similar to computer-based denial of service attacks). This is made easier because the fax transmission protocols compress the solid black image very well, so a very short fax call can produce many pages. Black faxes have been used