feat: Add merge labelmaps utility function

packages/cornerstone-render/src/volumeLoader.ts

@@ -299,7 +299,8 @@ export function createAndCacheDerivedVolume(
  */
 export function createAndCacheLocalVolume(
   options: LocalVolumeOptions,
-  uid: string
+  uid: string,
+  preventCache = false
 ): ImageVolume {
   const { scalarData, metadata, dimensions, spacing, origin, direction } =
     options
@@ -360,6 +361,10 @@ export function createAndCacheLocalVolume(
     sizeInBytes: numBytes,
   })
 
+  if (preventCache) {
+    return derivedVolume
+  }
+
   const volumeLoadObject = {
     promise: Promise.resolve(derivedVolume),
   }

packages/cornerstone-tools/src/util/segmentation/createMergedLabelmap.ts

@@ -0,0 +1,60 @@
+import { IImageVolume } from '@precisionmetrics/cornerstone-render/src/types'
+import { createAndCacheLocalVolume } from '@precisionmetrics/cornerstone-render'
+import isEqual from '../math/vec3/isEqual'
+
+/**
+ * Given a list of labelmaps (with the possibility of overlapping regions),
+ * it generates a new labelmap with the same dimensions as the input labelmaps,
+ * by merging all the overlapping regions. This methods can be used
+ * to avoid double counting the segments in more than one labelmaps
+ *
+ * @param {} labelmaps
+ * @param {number} segmentIndex
+ * @returns {number} TMTV in ml
+ */
+function createMergedLabelmap(
+  labelmaps: Array<IImageVolume>,
+  segmentIndex = 1, // The segment index to use for the merged labelmap
+  uid = 'mergedLabelmap'
+): IImageVolume {
+  labelmaps.forEach(({ direction, dimensions, origin, spacing }) => {
+    if (
+      !isEqual(dimensions, labelmaps[0].dimensions) ||
+      !isEqual(direction, labelmaps[0].direction) ||
+      !isEqual(spacing, labelmaps[0].spacing) ||
+      !isEqual(origin, labelmaps[0].origin)
+    ) {
+      throw new Error('labelmaps must have the same size and shape')
+    }
+  })
+
+  const labelmap = labelmaps[0]
+
+  const arrayType = labelmap.scalarData.constructor
+  const outputData = new arrayType(labelmap.scalarData.length)
+
+  labelmaps.forEach((labelmap) => {
+    const { scalarData } = labelmap
+    for (let i = 0; i < scalarData.length; i++) {
+      if (scalarData[i] === segmentIndex) {
+        outputData[i] = segmentIndex
+      }
+    }
+  })
+
+  const options = {
+    scalarData: outputData,
+    metadata: labelmap.metadata,
+    spacing: labelmap.spacing,
+    origin: labelmap.origin,
+    direction: labelmap.direction,
+    dimensions: labelmap.dimensions,
+  }
+
+  const preventCache = true
+  const mergedVolume = createAndCacheLocalVolume(options, uid, preventCache)
+
+  return mergedVolume
+}
+
+export default createMergedLabelmap

packages/cornerstone-tools/src/util/segmentation/index.ts

@@ -8,6 +8,7 @@ import thresholdVolumeByRoiStats from './thresholdVolumeByRoiStats'
 import triggerLabelmapRender from './triggerLabelmapRender'
 import calculateSuvPeak from './calculateSuvPeak'
 import calculateTMTV from './calculateTMTV'
+import createMergedLabelmap from './createMergedLabelmap'
 
 export {
   getBoundingBoxAroundShape,
@@ -18,6 +19,7 @@ export {
   triggerLabelmapRender,
   calculateSuvPeak,
   calculateTMTV,
+  createMergedLabelmap,
 }
 
 export default {
@@ -29,4 +31,5 @@ export default {
   triggerLabelmapRender,
   calculateSuvPeak,
   calculateTMTV,
+  createMergedLabelmap,
 }

packages/cornerstone-tools/src/util/segmentation/thresholdVolumeByRange.ts

@@ -34,7 +34,7 @@ function thresholdVolumeByRange(
   referenceVolumes: IImageVolume[],
   labelmap: IImageVolume,
   options: ThresholdRangeOptions
-): void {
+): IImageVolume {
   if (referenceVolumes.length > 1) {
     throw new Error('thresholding more than one volumes is not supported yet')
   }
@@ -104,6 +104,7 @@ function thresholdVolumeByRange(
   })
 
   triggerLabelmapRender(renderingEngine, labelmap, labelmapImageData)
+  return labelmap
 }
 
 function worldToIndex(imageData, ain) {

packages/cornerstone-tools/src/util/segmentation/thresholdVolumeByRoiStats.ts

@@ -36,7 +36,7 @@ function thresholdVolumeByRoiStats(
   referenceVolumes: IImageVolume[],
   labelmap: IImageVolume,
   options: ThresholdRoiStatsOptions
-): void {
+): IImageVolume {
   if (referenceVolumes.length > 1) {
     throw new Error('thresholding more than one volumes is not supported yet')
   }
@@ -105,6 +105,7 @@ function thresholdVolumeByRoiStats(
 
   // Run threshold volume by the new range
   thresholdVolumeByRange(toolDataList, referenceVolumes, labelmap, rangeOptions)
+  return labelmap
 }
 
 function _worldToIndex(imageData, ain) {