ts with nal_unit_type equal to 1 or 5, but contains one or more NAL units with nal_unit_type equal to 6, 7, 8, 9, or 15; any access unit in which one or more NAL units with nal_unit_type equal to 7, 8, or 15 is present after the last NAL unit in the access unit with nal_unit_type equal to 1 or 5. The association of VCL NAL units to primary or redundant coded pictures is specified in clause H.7.4.1.2.5. The constraints for the detection of the first VCL NAL unit of a primary coded picture are specified in clause H.7.4.1.2.4. The constraint expressed in clause 7.4.1.2.3 on the order of a buffering period SEI message is replaced by the following constraints. When an SEI NAL unit containing a buffering period SEI message is present, the following applies: If the buffering period SEI message is the only buffering period SEI message in the access unit and it is not included in an MVC scalable nesting SEI message, the buffering period SEI message shall be the first SEI message payload of the first SEI NAL unit in the access unit. Otherwise (the buffering period SEI message is not the only buffering period SEI message in the access unit or it is included in an MVC scalable nesting SEI message), the following constraints are specified: When a buffering period SEI message that is not included in an MVC scalable nesting SEI message is present, this buffering period SEI message shall be the only SEI message payload of the first SEI NAL unit in the access unit. An MVC scalable nesting SEI message that includes a buffering period SEI message shall not include any other SEI messages and shall be the only SEI message inside the SEI NAL unit. All SEI NAL units that precede an SEI NAL unit that contains an MVC scalable nesting SEI message with a buffering period SEI message as payload in an access unit shall only contain buffering period SEI messages or MVC scalable nesting SEI messages with a buffering period SEI message as payload. Each prefix NAL unit shall be immediately followed by a NAL unit with equal to 1 or 5. H.7.4.1.2.4