icture area for a sub-picture scalable layer may additionally be indicated by the presence of sub-picture scalable layer SEI messages with layer_ic equal to value of layer id[ i ] for the current scalable layer. (b) When a VCL NAL unit of the target access unit set has dependency equal to dependency id| and contains any macroblock that resides inside the sub-picture area, it shall not contain any macroblock that resides outside of the sub-picture area. (c) The VCL NAL units of the current scalable layer are the coded slice NAL units of the target access unit set that have dependency_id, quality_id, and temporal_id equal to dependency_id[i] quality_id[ and temporal_id[i], respectively, and for which the macroblock specified by first mb in slice resides inside the specified sub-picture area and the associated prefix NAL units (when present). (d) For all access units sets that can be derived from the target access unit set by invoking the sub-bitstream extraction process as specified in clause G.8.8.1 with dIdTarget equal to dependency id[ and qIdTarget equal to any value in the range of 0 to 15, inclusive, as the inputs, the following constraint shall be obeyed: No sample value outside the sub-picture area and no sample value at a fractional sample position that is derived using one or more sample values outside the sub-picture area is used, in the decoding process as specified in clause G.8, for inter prediction of any sample within the sub-picture area. When the target access unit set contains any primary coded VCL NAL unit with particular values of dependency id, quality id, and temporal_id, the scalability information SEI message shall contain information for a exactly one scalable layer with dependency_id[ quality_id[i], and temporal_id[ equal to the particular values of dependency_io quality_io and temporal_id respectively, and sub_pic_layer_flag[ equal to 0. NOTE 7 - The scalability information SEI message may additionally contain information for one or more scalable layers with dependency_id[i quality_id[i]