US Patent 9621919 Multi-layer video file format designs

A computing device generates a file that comprises a track box that contains metadata for a track in the file. Media data for the track comprises a sequence of samples, each of the samples being a video access unit of multi-layer video data. As part of generating the file, the computing device generates, in the file, a sub-sample information box that contains flags that specify a type of sub-sample information given in the sub-sample information box. When the flags have a particular value, a sub-sample corresponding to the sub-sample information box contains exactly one coded picture and zero or more non-Video Coding Layer (VCL) Network Abstraction Layer (NAL) units associated with the coded picture.