The Base64 module provides for the encoding (#encode64) and decoding (#decode64) of binary data using a Base64 representation.
The following particular features are also provided:
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encode into lines of a given length (#b64encode)
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decode the special format specified in RFC2047 for the representation of email headers (decode_b)
Example
A simple encoding and decoding.
require "base64" enc = Base64.encode64('Send reinforcements') # -> "U2VuZCByZWluZm9yY2VtZW50cw==\n" plain = Base64.decode64(enc) # -> "Send reinforcements"
The purpose of using base64 to encode data is that it translates any binary data into purely printable characters. It is specified in RFC 2045 (http://www.faqs.org/rfcs/rfc2045.html).
Real life use
If you’re wondering what the base64 format is used for, here are some examples:
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HTTP Basic authentication: encode your username and password as one string, and add it as a header of an HTTP request. When a page requiring basic authentication gets called from a browser it results in a generic Username/Password dialog from that browser. See also http://en.wikipedia.org/wiki/Basic_access_authentication
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Encode the binary content of images to base64 and embed it in XML documents, for example in web services
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For more information see http://en.wikipedia.org/wiki/Base64
Just note that the encoded (character) data is about 30% larger than un-encoded (binary) data.