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Encapsulated PostScript (EPS) is a DSC-conforming PostScript document with additional restrictions which is intended to be usable as a graphics file format. In other words, EPS files are more-or-less self-contained, reasonably predictable PostScript documents that describe an image or drawing and can be placed within another PostScript document. Simply, an EPS file is a PostScript program, saved as a single file that includes a low-resolution preview "encapsulated" inside of it, allowing some programs to display a preview on the screen. At minimum, an EPS file contains a ''BoundingBox'' DSC comment, describing the rectangle containing the image described by the EPS file. Applications can use this information to lay out the page, even if they are unable to directly render the PostScript inside. EPS, together with DSC's Open Structuring Conventions, form the basis of early versions of the Adobe Illustrator Artwork file format. == Identification == Because of the different ways in which EPS previews are handled, there is no one way to identify an EPS file. * A Windows-format EPS file containing a TIFF or WMF preview must start with the four bytes containing, in hexadecimal, C5 D0 D3 C6. (This sequence, rendered in ISO/IEC 8859-1, yields “ÅÐÓÆ”, loosely reminiscent of Adobe.) These bytes comprise the first four bytes of a 30-byte header, whose remaining fields are six unsigned 32-bit integers and a 16-bit checksum. (Often two zero bytes follow the header.) EPS files having "DOS" WMF or TIFF previews are widespread on all platforms. * In all other cases an EPS file must start with a line %!PS-Adobe-a.b EPSF-c.d where a, b, c and d are all single digit numbers.* * A Mac-format EPS file is accompanied by a resource fork. The preview is a PICT resource with ID 256. An EPS file on the Mac is expected to have a file type code of "EPSF", whether or not it has a preview. * * An EPSI file will contain a line starting %%BeginPreview: in the DSC prolog.* * In many cases no preview is present at all. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Encapsulated PostScript」の詳細全文を読む スポンサード リンク
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