Dicom.Data.DcmDataset.GetSS C# (CSharp) Method

        public DcmSignedShort GetSS(DicomTag tag)
        {
            DcmElement elem = GetElement(tag);
            if (elem is DcmSignedShort)
                return elem as DcmSignedShort;
            if (elem != null)
                throw new DicomDataException("Tried to access element with incorrect VR");
            return null;
        }

		private void Load(DcmDataset ds) {
			_rows = ds.GetUInt16(OverlayTag(DicomTags.OverlayRows), 0);
			_columns = ds.GetUInt16(OverlayTag(DicomTags.OverlayColumns), 0);
			_type = ds.GetString(OverlayTag(DicomTags.OverlayType), "Unknown");

			DicomTag tag = OverlayTag(DicomTags.OverlayOrigin);
			if (ds.Contains(tag)) {
				short[] xy = ds.GetSS(tag).GetValues();
				if (xy != null && xy.Length == 2) {
					_originX = xy[0];
					_originY = xy[1];
				}
			}

			_bitsAllocated = ds.GetUInt16(OverlayTag(DicomTags.OverlayBitsAllocated), 1);
			_bitPosition = ds.GetUInt16(OverlayTag(DicomTags.OverlayBitPosition), 0);

			tag = OverlayTag(DicomTags.OverlayData);
			if (ds.Contains(tag)) {
				DcmElement elem = ds.GetElement(tag);
				_data = elem.ByteBuffer.ToBytes();
			}

			_description = ds.GetString(OverlayTag(DicomTags.OverlayDescription), String.Empty);
			_subtype = ds.GetString(OverlayTag(DicomTags.OverlaySubtype), String.Empty);
			_label = ds.GetString(OverlayTag(DicomTags.OverlayLabel), String.Empty);

			_frames = ds.GetInt32(OverlayTag(DicomTags.NumberOfFramesInOverlay), 1);
			_frameOrigin = ds.GetUInt16(OverlayTag(DicomTags.ImageFrameOrigin), 1);

			//TODO: include ROI
		}