Extensions of intra coding modes in video coding are described. One example is a method for video processing, comprising: generating, for a conversion between a current video block of a video and a bitstream representation of a video, a set of extended intra prediction modes (IPMs) associated with the current video block by revising a set of existing IPMs to include at least one new coding method, wherein the new coding method is different from coding methods in the existing IPMs and is to be treated as IPM; and performing the conversion based on the set of extended IPMs.