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Questions tagged [ascii85]

ASCII85 or Base85 is a binary to text encoding system.

ASCII85 (Base85) is a binary to text encoding system created by Paul E. Rutter. ASCII85 encoding is compatible with 7-bit and 8-bit MIME. ASCII85 is used in PostScript (PS) and Portable Document Format (PDF) file formats.

ASCII85 is similar to Base64, It uses 5 ASCII characters to code 4 bytes of binary data whereas in Base64 4 characters are used to code 3 bytes. ASCII85 has less overhead than Base64 as the ASCII85 encoded data size is ¹⁄₄ larger than the original size compared to ¹⁄₃ increase if encoded by Base64.

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Base64 encoding vs Ascii85 encoding

My project at work is using the Jackson JSON serializer to convert a bunch of Java objects into Strings in order to send them to REST services. Some of these objects contain sensitive data, so I've written custom serializers to serialize these…
Zim-Zam O'Pootertoot
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how to encode/decode ascii85 in javascript

I was looking for an alternative to Base64 which works fine on Unicode characters. I have found ASCII85 which works great however I found no code or command doing that in JS. I just found this link which does not work for international characters…
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Implement Atwood's Equipping our ASCII armor in PHP

I'm trying to implement in PHP something similar to Jeff Atwood's Equipping our ASCII armor. Here's C# Implementation of ASCII85. Here's PHP Implementation of ASCII85 Here's how I convert the string to byte array: $byteArr =…
Sfisioza
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Base85 aka ASCII85 java projects

Does anyone know about any other than com.idataconnect.lib.ascii85codec java projects that do something like org.apache.commons.codec.binary.Base64 class?
MatBanik
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What is the "Adobe implementation" of ASCII85 encoding that Python emulates?

In the documentation for the base64 module, the base64.a85encode function takes an adobe parameter, which is described as follows: adobe controls whether the encoded byte sequence is framed with <~ and ~>, which is used by the Adobe…
jl6
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How to display an ascii85 encoded picture

I try to display an ascii85 encoded image, like: or I found several examples on base64 files, but nothing about ascii85... What do you think? Thanks
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PostScript ASCII85Decode filter

I'm trying to use PostScript's ASCII85Decode filter. Adding the following line to my PS file works fine, i.e. the letters XYZ are shown correctly on the page: 200 300 translate 0 0 moveto (XYZ) show I then ASCII85-encoded the above line using an…
YSJ
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C# implementation of Z85 encoding

Is anyone aware of a C# implementation of the Z85 character encoding specification? I have found the C/C++ library by artemkin, but would like a native C# library if one exists.
Adam Smith
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A shorter UUID, ASCII85 with PHP

I read about the UUID v4 and it's virtually unique, and that's what I need. The problem is, it's a too large number, is it possible to generate UUID's like Facebook or Twitter with fewer characters? I read some post, where you can shrink this code…
punchi
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Convert Binary/Hex to Base91 / Ascii85 / Base64

I need an JS encoder to base91 or Ascii85 for a binary number. I do have a google sheet, which looks likes as follows: Code is: function columnToLetter(column) { //https://stackoverflow.com/a/21231012/14226613 var temp, letter = ''; while…
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Encoding an array for url in PHP

I have been working on some QR codes, I need to pass an array to the QR with the data but it needs encoding. The data itself is a json_array which is used to generate a PDF. If I use base64 encoding the QR code is stupidly large, and when using…
Christopher Shaw
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ascii85 decoder algorithm for adobe fails in some cases

I am trying to develop a Ascii85 decoder in c++, in order to parse a bitmap file from an adobe illustrator file (*ai). I have found an algorithm in java here and I have tried to rewrite it in c++. The problem is that I have some cases that my…
willy
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A PostScript File not converted by Acrobat Distiller but converted by GhostScript

I have a JPEG file that I have converted to PostScript with jpeg2ps (the JPEG picture is coded in ASCII85 inside the PostScript file which is only a wrapper). The resulting PostScript file is image.ps. When converting to PDF, Adobe Distiller creates…
F. Pantigny
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Swap an image in an .eps file?

I'm trying to figure out how to swap an image that is embedded in an .eps file with a jpeg. My "template" .eps file contains several sections that look this, each representing a different image: Adobe_AGM_Image/AGMIMG_fl cf /ASCII85Decode fl…
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Decoding and decompressing AI9_DataStream within .eps files

Context: I am attempting to automate the inspection of eps files to detect a list of attributes, such as whether the file contains locked layers, embedded bitmap images etc. So far we have found some of these things can be detected via inspection of…
Hub
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