Pass data to this method to encode. This method should be called repeatedly until there is no more data to encode. Once there is no more data to encode then you should call the FinishEncoding function which will finish any buffered bytes that did not add up to pairs of 3, reset internal buffers and clean up.
The size of the buffer passed to this function each round does not mater regarding the outcome, but its faster if the buffer size is dividable by 3. (When its dividable by 3 then internal buffering is greatly reduced).