A method of video processing is described. The method includes determining, for a conversion between a current video block of a current picture of a video and a coded representation of the video, an applicability of an alternative interpolation filter, wherein the applicability of the alternative interpolation filter indicates whether to apply the alternative interpolation filter in the conversion; and performing the conversion based on the determining; wherein the applicability of the alternative interpolation filter is determined based on whether a reference picture resampling in which a reference picture of the current picture is resampled to perform the conversion is used.