Ascii85

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== Identification ==
 
== Identification ==
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Generic Ascii85 data often has a "<code>&lt;~</code>" prefix, and a "<code>~&gt;</code>" suffix, but this is not universal. Evidently, in PDF and PostScript, only the suffix is usually present.
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In PostScript, the "<code>&lt;~</code>" token marks the beginning of an ASCII base-85 string literal, hence it is not part of the encoded data. The "<code>~&gt;</code>" EOD marker, on the other hand, should be regarded as part of the encoded data, since it is added by the ASCII85Encode filter when it is closed.
  
 
There is also a [[uuencoding]]-like format, delimited by lines that begin with "<code>xbtoa Begin</code>" and "<code>xbtoa End</code>".
 
There is also a [[uuencoding]]-like format, delimited by lines that begin with "<code>xbtoa Begin</code>" and "<code>xbtoa End</code>".

Revision as of 11:40, 22 June 2015

File Format
Name Ascii85
Ontology
Ascii85, or Base85, is a binary-to-text encoding. It is similar in concept to Base64 and Uuencode. It is often used in PDF and PostScript files, and rarely anywhere else. There are several varieties of it.

Identification

In PostScript, the "<~" token marks the beginning of an ASCII base-85 string literal, hence it is not part of the encoded data. The "~>" EOD marker, on the other hand, should be regarded as part of the encoded data, since it is added by the ASCII85Encode filter when it is closed.

There is also a uuencoding-like format, delimited by lines that begin with "xbtoa Begin" and "xbtoa End".

Software

Links

Retrieved from "http://fileformats.archiveteam.org/index.php?title=Ascii85&oldid=22859"
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