The Segmentation IOD specifies a multi-frame image representing a classification of pixels in one or more referenced images. Segmentations are either binary or fractional. If the referenced images have a defined Frame of Reference, the Segmentation Instance shall have the same Frame of Reference and is not required to have the same spatial sampling or extent as the referenced images. If the referenced image does not have a defined Frame of Reference, the Segmentation Instance shall have the same spatial sampling and extent as the referenced image.

The Segmentation IOD does not include the full set of acquisition parameters of the referenced images, e.g., cardiac phase. An application rendering or processing the segmentation may need to access the referenced images for such information.