GPL Ghostscript 9.06 and PDF/A conformance with modern color profiles

Last update: 31 July 2018

Overview

When using the current color profiles from www.color.org the PDF/A documents generated with GPL Ghostscript produce the error "The value of the key N is 4 but must be 3." in most validators.

Details

This error message is generated because the definition file "PDFA_def.ps" of Ghostscript 9.06 expects that all non grayscale color profiles are using the CMYK color space, which is no longer true for the recommended color profiles from www.color.org , this assumption can be changed by editing the definition file.

To change the assumed color profile of Ghostscript 9.06 simple change the value 4 to 3 in the following line inside the file "PDFA_def.ps" as shown below:

       [{icc_PDFA} <</N systemdict /ProcessColorModel get /DeviceGray eq {1} {

        4

       } ifelse >> /PUT pdfmark

       [{icc_PDFA} <</N systemdict /ProcessColorModel get /DeviceGray eq {1} {

        3

       } ifelse >> /PUT pdfmark