US Patent 9749661 Sub-streams for wavefront parallel processing in video coding

A video encoder signals whether WPP is used to encode a picture of a sequence of video picture. If WPP is used to encode the picture, the video encoder generates a coded slice NAL unit that includes a plurality of sub-streams, each of which includes a consecutive series of bits that represents one encoded row of coding tree blocks (CTBs) in a slice of the picture. A video decoder receives a bitstream that includes the coded slice NAL unit. Furthermore, the video decoder may determine, based on a syntax element in the bitstream, that the slice is encoded using WPP and may decode the slice using WPP.