nl_tokens: Get the base64 encoding
pl_tokens: function ( fn ) { fn = fn || console . <mask> . bind ( console ) ; var buffers = [ ] ; var base64 = new Stream ( ) ; base64 . readable = base64 . writable = true ; base64 . write = function ( data ) { buffers . push ( data ) ; } ; base64 . end = function ( ) { fn ( Buffer . concat ( buffers ) . toString ( 'base64' ) ) ; } this . _png . pack ( ) . pipe ( base64 ) ; }