Video encoding and decoding

An apparatus comprising at least one processor and at least one memory, said at least one memory stored with code thereon, which when executed by said at least one processor, causes an apparatus to perform at least the following:

• encoding a scalable nesting supplemental enhancement information (SEI) message;
• associating the scalable nesting SEI message with a bitstream comprising at least two layers and with a first intra random access point (IRAP) picture within the bitstream;
• including a buffering period SEI message in the scalable nesting SEI message;
• indicating, in the scalable nesting SEI message, that the buffering period SEI message applies to more than one layer of the associated bitstream;
• indicating, in the buffering period SEI message, at least one buffering parameter applying when cross-layer random access skipped (CL-RAS) pictures of the first IRAP picture are not present in the bitstream, where CL RAS picture in a particular layer is a picture preceding, in decoding order, an IRAP picture in that particular layer from which the decoding of that particular layer can be initialized.

A computer program product embodied on a non-transitory computer readable medium, comprising computer program code configured to, when executed on at least one processor, cause an apparatus or a system to:

• encode a scalable nesting supplemental enhancement information (SEI) message;
• associate the scalable nesting SEI message with a bitstream comprising at least two layers and with a first intra random access point (IRAP) picture within the bitstream;
• include a buffering period SEI message in the scalable nesting SEI message;
• indicate, in the scalable nesting SEI message, that the buffering period SEI message applies to more than one layer of the associated bitstream;
• indicate, in the buffering period SEI message, at least one buffering parameter applying when cross-layer random access skipped (CL-RAS) pictures of the first IRAP picture are not present in the bitstream, where CL RAS picture in a particular layer is a picture preceding, in decoding order, an IRAP picture in that particular layer from which the decoding of that particular layer can be initialized.