PostScript Printer Description
Filename extension |
.ppd |
---|---|
Internet media type |
text/plain, application/vnd.cups-ppd |
Magic number | *PPD-Adobe |
Developed by | Adobe Systems |
PostScript Printer Description (PPD) files are created by vendors to describe the entire set of features and capabilities available for their PostScript printers.
A PPD also contains the PostScript code (commands) used to invoke features for the print job. As such, PPDs function as drivers for all PostScript printers, by providing a unified interface for the printer's capabilities and features. For example, a generic PPD file for all models of HP Color LaserJet contains:
*% ================================= *% Basic Device Capabilities *% ================================= *LanguageLevel: "2" *ColorDevice: True *DefaultColorSpace: CMYK *TTRasterizer: Type42 *FileSystem: False *Throughput: "10"
which specifies that the printer understands PostScript Level 2, is a color device, and so forth. The PPD can describe allowable paper sizes, memory configurations, the minimum font set for the printer, and even specify a tree-based user interface for printer-specific configuration.
CUPS
CUPS uses PPD drivers for all of its PostScript printers, and has even extended the concept to allow for PostScript printing to non-PostScript printing devices, by directing output through a CUPS filter. Such a file is no longer a standard PPD, but rather a "CUPS-PPD". CUPS clients usually read the current PPD file from the server every time a new print job is created.
Windows
Microsoft Windows also uses PPD files but converts these to a binary .BPD file format before using them. These are normally stored in C:\WINDOWS\system32\spool\drivers\w32x86\3 on a x86 system, or C:\Windows\System32\spool\drivers\x64\3 on a 64 bit system. Updating the PPD files requires removing and then reinstalling the printer.
MIME Type
The MIME type for the CUPS variant of PPD is application/vnd.cups.ppd.[1]