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Version: Version 3.3 - Segmentation Support 🚧

Module: SOP Class Handler

Overview​

This module defines how a specific DICOM SOP class should be processed to make a displaySet, something that can be hung in a viewport. An extension can register a SOP Class Handler Module by defining a getSopClassHandlerModule method. The SOP Class.

The mode chooses what SOPClassHandlers to use, so you could process a series in a different way depending on mode within the same application.

SOPClassHandler is a bit different from the other modules, as it doesn't provide a 1:1 schema for UI or provide its own components. It instead defines:

  • sopClassUIDs: an array of string SOP Class UIDs that the getDisplaySetFromSeries method should be applied to.
  • getDisplaySetFromSeries: a method that maps series and study metadata to a display set

A displaySet has the following shape:

return {
Modality: 'MR',
displaySetInstanceUIDD
SeriesDate,
SeriesTime,
SeriesInstanceUID,
StudyInstanceUID,
SeriesNumber,
FrameRate,
SeriesDescription,
isMultiFrame,
numImageFrames,
SOPClassHandlerId,
}

Example SOP Class Handler Module​

import ImageSet from '@ohif/core/src/classes/ImageSet';


const sopClassDictionary = {
CTImageStorage: "1.2.840.10008.5.1.4.1.1.2",
MRImageStorage: "1.2.840.10008.5.1.4.1.1.4",
};


// It is important to note that the used SOPClassUIDs in the modes are in the order that is specified in the array.
const sopClassUids = [
sopClassDictionary.CTImageStorage,
sopClassDictionary.MRImageStorage,
;

const makeDisplaySet = (instances) => {
const instance = instances[0];
const imageSet = new ImageSet(instances);

imageSet.setAttributes({
displaySetInstanceUID: imageSet.uid,
SeriesDate: instance.SeriesDate,
SeriesTime: instance.SeriesTime,
SeriesInstanceUID: instance.SeriesInstanceUID,
StudyInstanceUID: instance.StudyInstanceUID,
SeriesNumber: instance.SeriesNumber,
FrameRate: instance.FrameTime,
SeriesDescription: instance.SeriesDescription,
Modality: instance.Modality,
isMultiFrame: isMultiFrame(instance),
numImageFrames: instances.length,
SOPClassHandlerId: `${id}.sopClassHandlerModule.${sopClassHandlerName}`,
});

return imageSet;
};

getSopClassHandlerModule = () => {
return [
{
name: 'stack,
sopClassUids,
getDisplaySetsFromSeries: makeDisplaySet,
},
];
};

More examples :​

You can find another example for this mapping between raw metadata and displaySet for DICOM-SR extension.

@ohif/viewer usage​

We use the sopClassHandlerModules in DisplaySetService where we transform instances from the raw metadata format to a OHIF displaySet format. You can read more about DisplaySetService here.