FIELD: information technology.SUBSTANCE: method for video data decoding comprises determining a value of a syntax element that signals whether the delete delay parameters from the sub-picture level coded pictures buffer (CPB) are present in the supplementary extension information (SEI) of the picture timing; regardless of the value of the variable the derivation of the arrival time in the CPB for the access unit (AU) and the nominal delete time for AU at the AU level while the CPB operates at the AU level when the value of the variable is 0 and the CPB operates at the sub-picture level when the value of the variable is 1; setting the nominal decoding unit (DU) removal time on the basis of the above syntax element; on the basis of the fact that the variable is 1 and either the low_delay_hrd_flag is 0 or the nominal DU deletion time is greater or equal to the end arrival time of the decoding unit (DU) to the CPB setting the deletion time of the decoding unit (DU) from the CPB equal to the nominal DU deletion time; and DU decoding during deleting of the decoding unit (DU) from the CPB.EFFECT: increased fault tolerance.8 cl 16 dwg 4 tbl