In addition to the primary coded picture, an access unit may also contain one or more redundant coded pictures or other NAL units not containing slices or slice data partitions of a coded picture.
英
美
- 除了基本编码图象外,一个访问单元也可能包含一个或者多个冗余编码图象,以及不包含编码图象片数据的NAL单元。