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**Status**: This project is feature-complete. With the exception of fixes to reported bugs, no further development will take place.
# Ascii85
## Description
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][PLRM]) page 131
and [Wikipedia](https://en.wikipedia.org/wiki/Ascii85) for more information
about the format.
[PLRM]: https://web.archive.org/web/20161222092741/https://www.adobe.com/products/postscript/pdfs/PLRM.pdf
## Installation
`$ gem install Ascii85`
> [!IMPORTANT]
> Note that the gem name is capitalized.
## Usage
```ruby
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](https://www.rubydoc.info/gems/Ascii85/).
## Command-line utility
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
```
## License
Ascii85 is distributed under the MIT License. See the accompanying LICENSE file
for details.
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