Reference picture resampling activation in video coding

An apparatus for processing video data comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to:

• perform a conversion between a video comprising a video picture that includes a video slice and a bitstream of the video,
• wherein the bitstream conforms to a format rule, and
• wherein the format rule specifies that, in case a slice type of the video slice is P and a temporal motion vector prediction for the video picture is enabled, usage of reference picture resampling (RPR) for a reference picture in a specific collocated reference picture list is disabled, wherein the reference picture is indicated by a first syntax element, which specifies a reference index of a collocated picture used for the temporal motion vector prediction,
• wherein the format rule further specifies that a value of first certain information in a slice header for the video slice indicates the collocated picture used for the temporal motion vector prediction is derived from a reference list 0 when the slice type of the video slice is P and a value of a third syntax element in a picture header of the video picture indicates that the temporal motion vector prediction is enabled for the video picture.

A non-transitory computer-readable storage medium storing instructions that cause a processor to:

• perform a conversion between a video comprising a video picture that includes a video slice and a bitstream of the video,
• wherein the bitstream conforms to a format rule, and
• wherein the format rule specifies that, in case a slice type of the video slice is P and a temporal motion vector prediction for the video picture is enabled, usage of reference picture resampling (RPR) for a reference picture in a specific collocated reference picture list is disabled, wherein the reference picture is indicated by a first syntax element, which specifies a reference index of a collocated picture used for the temporal motion vector prediction,
• wherein the format rule further specifies that a value of first certain information in a slice header for the video slice indicates the collocated picture used for the temporal motion vector prediction is derived from a reference list 0 when the slice type of the video slice is P and a value of a third syntax element in a picture header of the video picture indicates that the temporal motion vector prediction is enabled for the video picture.