Encapsulated PostScript
| Encapsulated PostScript | |
|---|---|
| File extension : |
.eps .epsf .epsi
|
| MIME type : | image / x-eps |
| Developed by: | Adobe Inc. |
| Initial release: | 1987 |
| Extended by: | PostScript |
An encapsulated Postscript file ( EPS file) is a graphic file in the PostScript page description language that meets special requirements in order to enable it to be integrated into a document. In particular, in contrast to general PostScript, EPS only ever describes one page. The format was published in 1987 by Adobe together with Aldus , the then manufacturer of PageMaker , and Altsys , which developed vector graphics and font editors .
An EPS file contains object, raster graphics and separation data and is lossless. Also fonts can be embedded. Since importing applications do not have to have a PostScript interpreter , an EPS file can optionally also contain a preview in lower resolution (see preview image), which can serve as a placeholder in the screen view.
Encapsulated PostScript was developed because it is difficult to embed any graphic in PostScript format in other PostScript files. Even determining the height and width of a PostScript graphic is not easily possible. Therefore, EPS files contain information about the so-called bounding box . The bounding box is the smallest axially parallel rectangle that can be drawn around a printable object. Since it is possible that the embedded code has undesirable effects on the interpretation of the code of the embedding document, further rules must be followed. An EPS graphic must, for example, after its interpretation, leave the operand stack in its original state and must not use any commands or other program structures that have a global effect on the entire document containing the EPS file. So is z. For example, the use of the erasepageoperator, which deletes the content of an entire page (and thus also the area outside the EPS graphic), is not permitted.
EPS files can, for example, be displayed on the screen with Ghostscript or converted for printing on a non-Postscript printer. The file extensions for EPS are .epsand less often .epsf. The latter is the abbreviation for " Encapsulated PostScript File ".
The EPS file format is considered obsolete because it has largely been replaced by the PDF format. The reason for this is also that it does not differentiate between bitmap and vector and therefore cannot be clearly assigned to an application due to its magic byte identifier. JPEG, TIFF or PSD files are mostly used as a replacement for bitmap EPS files. The Adobe Illustrator .ai or PDF format is suitable for vector EPS files.
Individual evidence
- ↑ Peter Vollenweider: EPS manual. Encapsulated PostScript. Hanser, Munich / Vienna 1989, ISBN 3-446-15835-9 , p. 1.
literature
- Thomas W. Lipp: Graphic formats. Microsoft Press, Unterschleißheim 1997, ISBN 3-86063-391-0 .