r_set_id(when a previous picture parameter set NAL unit with the same value of bic_parameter_set_id was present in the bitstream). NOTE 2 - A decoder must be capable of simultaneously storing the contents of the picture parameter sets for all values of bic_parameter_set_id. The content of the picture parameter set with a particular value of pic parameter_se is overwritten when a new picture parameter set NAL unit with the same value of pic_parameter_set_i is received. An SVC sequence parameter set RBSP includes parameters that can be referred to by one or more picture parameter set RBSPs or one or more SEI NAL units containing a buffering period SEI message. Each SVC sequence parameter set RBSP is initially considered not active at the start of the operation of the decoding process. At most one SVC sequence parameter set RBSP is considered as the active SVC sequence parameter set RBSP at any given moment during the operation of the decoding process, and when any particular SVC sequence parameter set RBSP becomes the active SVC sequence parameter set RBSP, the previously-active SVC sequence parameter set RBSP (if any) is deactivated. In addition to the active SVC sequence parameter set RBSP, zero or more SVC sequence parameter set RBSPs may be specifically active for layer representations (with a particular value of DQId less than DQIdMax) that may be referred to through inter-layer prediction in decoding the target layer representation. Such an SVC sequence parameter set RBSP is referred to as active layer SVC sequence parameter set RBSP for the particular value of DQId (less than DQIdMax). The restrictions on active SVC sequence parameter set RBSPs also apply to active layer SVC sequence parameter set RBSPs with a particular value of DQId. For the following specification in this clause, the activating buffering period SEI message is specified as follows: If the access unit contains one or more buffering period SEI messages that are included in a scalable nesting SEI message and are associated with values of DQId