class MultiToSingle
        {
            public Keyword Group;
            public Keyword GroupItem;
            public Keyword TopLevelItem;

            public MultiToSingle(Keyword group, Keyword groupItem, Keyword topLevelItem)
            {
                Group = group;
                GroupItem = groupItem;
                TopLevelItem = topLevelItem;
            }
            public MultiToSingle(Keyword group, Keyword groupItem)
            {
                Group = group;
                GroupItem = groupItem;
                TopLevelItem = groupItem;
            }
        }

        static MultiToSingle[] Lookup = new MultiToSingle[]
        {
            //basic
            new MultiToSingle(Keyword.PlaneOrientationSequence, Keyword.ImageOrientationPatient),
            new MultiToSingle(Keyword.PixelMeasuresSequence, Keyword.SliceThickness),
            new MultiToSingle(Keyword.PixelMeasuresSequence, Keyword.PixelSpacing),
            new MultiToSingle(Keyword.FrameVOILUTSequence, Keyword.WindowCenter),
            new MultiToSingle(Keyword.FrameVOILUTSequence, Keyword.WindowWidth),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleIntercept),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleSlope),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleType),
            new MultiToSingle(Keyword.FrameContentSequence, Keyword.FrameAcquisitionNumber, Keyword.InstanceNumber),
            new MultiToSingle(Keyword.PlanePositionSequence, Keyword.ImagePositionPatient),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleIntercept),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleSlope),
            new MultiToSingle(Keyword.PixelValueTransformationSequence, Keyword.RescaleType),
            new MultiToSingle(Keyword.FrameAnatomySequence, Keyword.AnatomicRegionSequence),

            //MR from sample  

            new MultiToSingle(Keyword.MRImagingModifierSequence, Keyword.PixelBandwidth),
            new MultiToSingle(Keyword.MRImagingModifierSequence, Keyword.TransmitterFrequency, Keyword.ImagingFrequency),
            new MultiToSingle(Keyword.MRReceiveCoilSequence, Keyword.ReceiveCoilName),
            new MultiToSingle(Keyword.MRTransmitCoilSequence, Keyword.TransmitCoilName),
            new MultiToSingle(Keyword.MRTimingAndRelatedParametersSequence, Keyword.RepetitionTime),
            new MultiToSingle(Keyword.MRTimingAndRelatedParametersSequence, Keyword.EchoTrainLength),
            new MultiToSingle(Keyword.MRTimingAndRelatedParametersSequence, Keyword.FlipAngle),
            new MultiToSingle(Keyword.MRTimingAndRelatedParametersSequence, Keyword.RepetitionTime),
            new MultiToSingle(Keyword.MREchoSequence, Keyword.EffectiveEchoTime, Keyword.EchoTime), // 3rd param!

            // CT from sample
            new MultiToSingle(Keyword.CTAcquisitionDetailsSequence, Keyword.DataCollectionDiameter),
            new MultiToSingle(Keyword.CTAcquisitionDetailsSequence, Keyword.GantryDetectorTilt),
            new MultiToSingle(Keyword.CTAcquisitionDetailsSequence, Keyword.TableHeight),
            new MultiToSingle(Keyword.CTAcquisitionDetailsSequence, Keyword.RotationDirection),
            new MultiToSingle(Keyword.CTGeometrySequence, Keyword.DistanceSourceToDetector),
            new MultiToSingle(Keyword.CTReconstructionSequence, Keyword.ReconstructionDiameter),
            new MultiToSingle(Keyword.CTReconstructionSequence, Keyword.ConvolutionKernel),
            new MultiToSingle(Keyword.CTXRayDetailsSequence, Keyword.KVP),
            new MultiToSingle(Keyword.CTXRayDetailsSequence, Keyword.FilterType),
            new MultiToSingle(Keyword.CTXRayDetailsSequence, Keyword.FocalSpots),
            new MultiToSingle(Keyword.CTXRayDetailsSequence, Keyword.FilterMaterial),
        };

        public static IEnumerable<DicomImage> MakeSingleImages(this DicomImage multi, string newSOPclass, string UIDBase)
        {
            for (int frame = 1; frame <= multi.FrameCount; frame++)
            {
                // Pixel Data for 1 frame
                DicomImage Single = multi.SubImage(Point.Empty, multi.Size, 1, frame);

                // simple moves from functional group to top level
                foreach (var l in Lookup)
                {
                    var g = multi.DataSet.FunctionalGroupDataSet(l.Group, frame);
                    if (g != null)
                    {
                        var a = g[l.GroupItem];
                        if (a.Exists)
                            Single.DataSet.Add(l.TopLevelItem, a.Value);
                    }
                }

                if (Single.SOPClass == SOPClasses.EnhancedMR)
                {
                    // special handling for MR
                    switch (Single.DataSet[Keyword.EchoPulseSequence].Value as string)
                    {
                        case "SPIN":
                            Single.DataSet.Add(Keyword.ScanningSequence, "SE");
                            break;
                        case "GRADIENT":
                            Single.DataSet.Add(Keyword.ScanningSequence, "GR");
                            break;
                        case "BOTH":
                            Single.DataSet.Add(Keyword.ScanningSequence, "SE\\GR");
                            break;
                        default:
                            Single.DataSet.Add(Keyword.ScanningSequence, ""); // type 2
                            break;
                    }

                    // scanning variant
                    var Variant = new List<string>();

                    if (Single.DataSet[Keyword.SegmentedKSpaceTraversal].Value as string == "PARTIAL" || Single.DataSet[Keyword.SegmentedKSpaceTraversal].Value as string == "FULL")
                        Variant.Add("SK");

                    var MTC = Single.DataSet.FunctionalGroupOrRootLevelAttribute(Keyword.MRImagingModifierSequence, frame, Keyword.MagnetizationTransfer).Value as string;

                    if (Single.DataSet[Keyword.SteadyStatePulseSequence].Value is string && Single.DataSet[Keyword.SegmentedKSpaceTraversal].Value as string != "NONE")
                    {
                        if (Single.DataSet[Keyword.SteadyStatePulseSequence].Value as string == "TIME_REVERSED")
                            Variant.Add("TRSS");
                        else
                            Variant.Add("SS");
                    }

                    if (MTC == "ON_RESONANCE" || MTC == "OFF_RESONANCE")
                        Variant.Add("MTC");

                    if (Variant.Count == 0)
                        Variant.Add("NONE");

                    Single.DataSet.Add(Keyword.SequenceVariant, Variant);

                    // Scan Options
                    var Options = new List<string>();
                    // to fill in one day if we can find them !
                    Single.DataSet.Add(Keyword.ScanOptions, Options);
                }

                Single.DataSet.Remove(Keyword.SharedFunctionalGroupsSequence);
                Single.DataSet.Remove(Keyword.PerFrameFunctionalGroupsSequence);
                Single.DataSet.Add(Keyword.ImageType, "ORIGINAL\\PRIMARY");

                // other options to consider in MR handling

                //SP
                //spoiled
                //MP
                //MAG prepared
                //OSP
                //oversampling phase
                //NONE
                //no sequence variant

                Single.SOPClass = newSOPclass;
                Single.InstanceUID = UIDBase + frame.ToString();

                yield return Single;
            }
        }