 pictures for inter prediction as specified in clause G.8.2.3. use_ref_base_pic_flag equal to 0 specifies that reference base pictures are not used as reference pictures for inter prediction (i.e., only decoded pictures are used for inter prediction). The values of use_ref_base_pic_flag shall be the same for all NAL units of a dependency representation. discardable flag equal to 1 specifies that the current NAL unit is not used for decoding dependency representations that are part of the current coded picture or any subsequent coded picture in decoding order and have a greater value of dependency_ id than the current NAL unit. discardable flag equal to 0 specifies that the current NAL unit may be used for decoding dependency representations that are part of the current coded picture or any subsequent coded picture in decoding order and have a greater value of dependency_id than the current NAL unit. output_flag affects the decoded picture output and removal processes as specified in Annex C. The value of output_flag shall be the same for all NAL units of a dependency representation. For any particular value of dependency_id the value of output_flag shall be the same for both fields of a complementary field pair. reserved_three_2bits shall be equal to 3. Other values of reserved_three_2bits may be specified in the future by ITU-T ISO/IEC. Decoders shall ignore the value of reserved_three_2bits. G.7.4.1.2 Order of NAL units and association to coded pictures, access units, and video sequences This clause specifies constraints on the order of NAL units in the bitstream. Any order of NAL units in the bitstream obeying these constraints is referred to in the text as the decoding order of NAL units. Within a NAL unit, the syntax in clauses 7.3, D.1, E.1, G.7.3, G.13.1, and G.14.1 specifies the decoding order of syntax elements. Decoders shall be capable of receiving NAL units and their syntax elements in decoding order. G.7.4.1.2.1 Order of SVC sequence parameter set RBSPs and picture parameter set RBSPs and their activ