typedef enum lmrcImageDensityInfoMode {
mrcImageDensityInfoPercentageVolume =1,
mrcImageDensityInfoCentreOfGravity =2,
mrcImageDensityInfoMax =4,
mrcImageDensityInfoCentreOfGravitySD =8,
mrcImageDensityInfoMaxSD =16
} lmrcImageDensityInfoMode;