EXTERNAL PICTURES IN VIDEO CODING

A video encoder generates a syntax element that indicates whether a video unit of a current picture is predicted from an external picture. The external picture is in a different layer than the current picture. Furthermore, the video encoder outputs a video data bitstream that includes a representation of the syntax element. The video data bitstream may or may not include a coded representation of the external picture. A video decoder obtains the syntax element from the video data bitstream. The video decoder uses the syntax element in a process to reconstruct video data of a portion of the video unit.