within the same slice header shall not specify the current picture to be marked as "unused for reference". NOTE 2 - These constraints prohibit any combination of multiple memory_management_control_operation syntax elements that would specify the current picture to be marked as "unused for reference". However, some other combinations of memory_management_control_operation syntax elements are permitted that may affect the marking status of other reference pictures more than once in the same slice header. In particular, it is permitted for a memory_management_control_operatione equal to 3 that specifies a long-term frame index to be assigned to a particular short-term reference picture to be followed in the same slice header by a memory_management_control_operation equal to 2, 3, 4 or 6 that specifies the same reference picture to subsequently be marked as "unused for reference". Rec. ITU-T H.264 (01/2012) Table 7-9 Memory management control operation (memory_management_control_operation) values memory_management_control_operation Memory Management Control Operation End emory_management_control_operation syntax element loop Mark a short-term reference picture as "unused for reference" Mark a long-term reference picture as "unused for reference" Mark a short-term reference picture as "used for long-term reference" and assign a long-term frame index to it Specify the maximum long-term frame index and mark all long-term reference pictures having long-term frame indices greater than the maximum value as "unused for reference" Mark all reference pictures as "unused for reference" and set the MaxLongTermFrameIdx variable to "no long-term frame indices" Mark the current picture as "used for long-term reference" and assign a long-term frame index to it When decoding a field and a memory_management_control_operation command equal to 3 is present that assigns a long-term frame index to a field that is part of a short-term reference frame or part of a complementary reference field pair, another memory_management_control_operat