lib/io/filter

BASE64_INPUT_STREAM
 A base64 decoder. Plug it onto a base64-encoded stream.

BASE64_OUTPUT_STREAM
 A base64 encoder. The underlying stream gets encoded in base64 via this filter.

HTML_OUTPUT_STREAM
 Highly tailored filter that outputs well-formed HTML. Be aware that you cannot add any character as you
 want. You can filter this stream, but keep it available because it controls the tags.

QUOTED_PRINTABLE_INPUT_STREAM
 A quoted-printable decoder. Plug it onto a quoted-printable-encoded stream.

QUOTED_PRINTABLE_OUTPUT_STREAM
 A quoted-printable encoder. The underlying stream gets encoded in quoted-printable via this filter.