1. An apparatus comprising: a memory having stored therein at least one block of video data; a control circuit operably coupled to the memory and configured to: determine a primary prediction mode to employ when encoding the block of video data; determine, using a companion prediction mode lookup table, a corresponding companion prediction mode to correspond to the primary prediction mode; generate a mixed prediction for the block of video data by mixing a prediction formed using the primary prediction mode with a prediction formed using the companion prediction mode; following the generating of the mixed prediction for the block of video data, automatically update the companion prediction mode lookup table.