The stream format details payload of a decrypting stream processor. This is
a sparsely populated table to specify parameters necessary for decryption
other than the data stream. It is only necessary to update fields if they
changed, but not an error if the same value is repeated.
Pattern encryption utilizes a pattern of encrypted and clear 16 byte blocks
over the protected range of a subsample (the encrypted_bytes of a
SubsampleEntry). This structure specifies the number of encrypted data
blocks followed by the number of clear data blocks.
A byte range within a sample consisting of a clear byte range
followed by an encrypted byte range. This structure specifies the size of
each range in the subsample.
Properties accompanying a packet in an encrypted stream.