This document specifies the syntax, semantics, and decoding process for the AOMedia Film Grain Synthesis process. This process can be used and indicated with any video coding or transport mechanism. This includes the use of ITU-T T.35 based signaling, which is also specified in this document. Alternatively, the payload can be carried by other suitable transport mechanisms.
This specification is based on the film grain modeling process that is specified in the AV1 specification. However, this AOMedia Film Grain Synthesis process specification allows sending more than one film grain parameter set for a decoded picture. A decoder can apply the film grain synthesis process at a different resolution than the decoded picture resolution if the parameters for such resolution are present in the bitstream. A film grain parameter set that corresponds to the decoded picture resolution has to be present, which may be useful for certain AV1 film grain synthesis implementations.