The EPS File Extension

EPS files can be scaled to print at any size.

The EPS file format is used in graphic design and printing as well as scientific applications. EPS stands for Encapsulated PostScript, making EPS a special type of PostScript file. Adobe developed the EPS file type, which accurately describes the placement of images, text and objects on a single page.

PostScript Technology

PostScript is a file format that describes a document's entire contents. It uses vector imagery to describe the document instead of relying on bit map images. Because EPS files are based on vectors, PostScript compatible printers can scale the document to any size without a loss in image quality. PostScript is also a programming language. If you open a PostScript file in a text editor, you can read the code that describes the document.

Encapsulated PostScript Technology

PostScript files can be very complex, so the PostScript Document Structuring Conventions were developed to help define the structure of PostScript files. EPS files follow these conventions and describe the contents of only a single page. Designers can insert these files into longer PostScript files, just as they can insert photos in the JPEG format into longer documents. EPS files also include a preview thumbnail of the document, allowing programs without EPS support to display a preview of the document.

Creating EPS Files

You can create EPS files in a vector illustration program such as Adobe Illustrator. EPS files created in vector illustration programs will be superior to those created in painting or photography software such as Adobe Photoshop. This is because the fixed size of images created in bitmap imagery software do not scale as well as vector images. Additionally, scientific software such as MATLAB and Mathematica can produce EPS files for use in printing detailed charts and diagrams.

Converting EPS Files

Adobe Illustrator, Photoshop, Acrobat Professional, CorelDRAW and other programs that support EPS files can save the file in several other formats. Keep in mind, however, that converting the EPS file to a JPEG or other bitmap image will force you to decide the image's size. Increasing the bitmap image's size later will result in a loss of quality. Converting the file to a PDF may be a good choice if you want people to be able to view and print it from the free Acrobat Reader.

References

• Worcester Polytechnic Institute: Graphics File Formats; Darren Meyer
• Florida State University: EPS Files; John Burkardt