New in version 1.4: The convert_encoding filter was added in Twig 1.4.
The convert_encoding filter converts a string from one encoding to another. The first argument is the expected output charset and the second one is the input charset:
{{ data|convert_encoding('UTF-8', 'iso-2022-jp') }}
Note
This filter relies on the iconv or mbstring extension, so one of them must be installed. In case both are installed, mbstring is used by default (Twig before 1.8.1 uses iconv by default).