Add getOrientationFromCosines

ivmartel · Apr 25, 2024 · 2bf2845 · 2bf2845
1 parent a080f12
commit 2bf2845
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Showing 2 changed files with 31 additions and 18 deletions.
diff --git a/src/dicom/dicomElementsWrapper.js b/src/dicom/dicomElementsWrapper.js
@@ -13,8 +13,7 @@ import {
   getTagFromKey
 } from './dicomTag';
 import {isNativeLittleEndian} from './dataReader';
-import {Vector3D} from '../math/vector';
-import {Matrix33} from '../math/matrix';
+import {getOrientationFromCosines} from '../math/matrix';
 import {Spacing} from '../image/spacing';
 import {logger} from '../utils/logger';
 
@@ -698,22 +697,8 @@ export function getOrientationMatrix(dataElements) {
   // slice orientation (cosines are matrices' columns)
   // http://dicom.nema.org/medical/dicom/current/output/chtml/part03/sect_C.7.6.2.html#sect_C.7.6.2.1.1
   if (typeof imageOrientationPatient !== 'undefined') {
-    const rowCosines = new Vector3D(
-      parseFloat(imageOrientationPatient.value[0]),
-      parseFloat(imageOrientationPatient.value[1]),
-      parseFloat(imageOrientationPatient.value[2]));
-    const colCosines = new Vector3D(
-      parseFloat(imageOrientationPatient.value[3]),
-      parseFloat(imageOrientationPatient.value[4]),
-      parseFloat(imageOrientationPatient.value[5]));
-    const normal = rowCosines.crossProduct(colCosines);
-    /* eslint-disable array-element-newline */
-    orientationMatrix = new Matrix33([
-      rowCosines.getX(), colCosines.getX(), normal.getX(),
-      rowCosines.getY(), colCosines.getY(), normal.getY(),
-      rowCosines.getZ(), colCosines.getZ(), normal.getZ()
-    ]);
-    /* eslint-enable array-element-newline */
+    orientationMatrix =
+      getOrientationFromCosines(imageOrientationPatient.value);
   }
   return orientationMatrix;
 }

diff --git a/src/math/matrix.js b/src/math/matrix.js
@@ -498,4 +498,32 @@ function getVectorStringLPS(vector) {
   }
 
   return orientation;
+}
+
+/**
+ * Get the orientation matrix associated to the direction cosines.
+ * *
+ * @param {number[]} cosines The direction cosines.
+ * @returns {Matrix33} The orientation matrix.
+ */
+export function getOrientationFromCosines(cosines) {
+  let orientationMatrix;
+  if (typeof cosines !== 'undefined' && cosines.length === 6) {
+    const rowCosines = new Vector3D(
+      parseFloat(cosines[0]),
+      parseFloat(cosines[1]),
+      parseFloat(cosines[2]));
+    const colCosines = new Vector3D(
+      parseFloat(cosines[3]),
+      parseFloat(cosines[4]),
+      parseFloat(cosines[5]));
+    const normal = rowCosines.crossProduct(colCosines);
+    /* eslint-disable array-element-newline */
+    orientationMatrix = new Matrix33([
+      rowCosines.getX(), colCosines.getX(), normal.getX(),
+      rowCosines.getY(), colCosines.getY(), normal.getY(),
+      rowCosines.getZ(), colCosines.getZ(), normal.getZ()
+    ]);
+  }
+  return orientationMatrix;
 }