Over deze norm
A digital file is used to produce 16 step colour scales on a colour printer between the white paper and the 6 chromatic colours and black. The intended 16 step colour scales are defined in figures B4 and D4 of the ISO/IECtest charts for colour copiers according to ISO/IEC 15775. The digital file format may be PostScript (PS), Portable document (PDF), GIF, HTM or equivalent. Within the different file formats the 16 step colour scales are defined by 16 digital values between 0 and 1, e. g. by 0, 1/15, 2/15 to 15/15 in CMY coordinates. The first output is measured and by the linearization method (LM) of this Technical Report, a visually equally spaced output is produced in relative CIELAB units, e. g. between the white paper and the six device colours and black. There is a table of output values and a graph for the first and linearized output. This method produces a linear relationship between the linear digital input data and the output data on a visual relative CIELAB scale for the colour primaries. The visual uniformity of overprint scales can be improved by this method. The method is applicable for systems that do not have colour management or as a linearization method for devices that could be used as a setup_state for colour management. The aim of this method is to produce equal CIELAB spacing. The equal spacing of the steps achieved in the linearization method may be adapted to various purposes. The accuracy and repeatability of this method is expected to be within 6 CIELAB units. Other methods may be appropriate for applications requiring greater accuracy. Note: Any first output can be used for this linearization method (LM) even though the first output depends e. g. on application software, file format, printer driver, paper and other parameters.
||Information technology - Office machines - Device output of 16 colour scales, output linearization method (LM) and specification of the reproduction properties