Things like *Emacs or irssi do have quite good methods of guessing encodings. Maybe ICU has some, Adrien ?
Bad news : "ICU converters are not designed to perform any encoding autodetection." (http://userguide.icu-project.org/conversion/converters) At least ICU can convert : http://icu-project.org/apiref/icu4c/ucnv_8h.html#f4c967c5afa207d064c24e19256586b6
-- Adrien Destugues / PulkoMandy http://pulkomandy.ath.cx