Status: This project is feature-complete. With the exception of fixes to reported bugs, no further development will take place.

Ascii85 is a Ruby gem that provides methods for encoding/decoding Adobe's binary-to-text encoding of the same name.

See the Adobe PostScript Language Reference (archived version) page 131 and Wikipedia for more information about the format.

$ gem install Ascii85

require 'ascii85'

Ascii85.encode("Ruby")
=> "<~;KZGo~>"

Ascii85.decode("<~;KZGo~>")
=> "Ruby"

Ascii85.extract("Foo<~;KZGo~>Bar")
=> ";KZGo"

Ascii85.decode_raw(";KZGo")
=> "Ruby"

In addition, Ascii85.encode can take a second parameter that specifies the length of the returned lines. The default is 80; use false for unlimited.

Ascii85.decode expects the input to be enclosed in <~ and ~> — it ignores everything outside of these, while Ascii85.decode_raw assumes that the entire String passed in is encoded in Ascii85. If you need to, you can use Ascii85.extract to find and extract the first substring of the input that is enclosed by the <~ and ~> delimiters.

The output of Ascii85.decode and Ascii85.decode_raw will be a String that has the ASCII-8BIT encoding, so you may have to use String#force_encoding to convert it to the desired encoding.

For further options, see the Documentation.

This gem includes ascii85, a command-line utility modeled after base64 from the GNU coreutils. It can be used to encode/decode Ascii85 directly from the command-line:

Usage: ascii85 [OPTIONS] [FILE]
Encodes or decodes FILE or STDIN using Ascii85 and writes to STDOUT.
    -w, --wrap COLUMN                Wrap lines at COLUMN. Default is 80, use 0 for no wrapping
    -d, --decode                     Decode the input
    -h, --help                       Display this help and exit
    -V, --version                    Output version information

Ascii85 is distributed under the MIT License. See the accompanying LICENSE file for details.