摘要 |
Disclosed herein is a technique for delimiting the alpha channel at the NAL layer in codecs like H.264 to facilitate the optional nature of the alpha channel. In coded video sequences that include alpha, there is one alpha picture for every primary coded (e.g., luma-chroma) picture, and the coded alpha picture is contained in the same access unit as its corresponding primary coded picture. The alpha coded slice NAL units of each access unit are sent after the NAL units of the primary coded picture and redundant coded pictures, if any. The presence or absence of the alpha NAL units does not affect the decoding of the remaining NAL units in any way.
|