From 01b63dceb3f2fa8cac3114959a220daf5b67b440 Mon Sep 17 00:00:00 2001
From: Ouwen Huang <ouwen.huang@duke.edu>
Date: Sat, 4 Feb 2023 05:24:53 +0000
Subject: [PATCH] fix: scaling view

---
 src/imageLoader/createImage.js | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/imageLoader/createImage.js b/src/imageLoader/createImage.js
index decfe61d..179baae9 100644
--- a/src/imageLoader/createImage.js
+++ b/src/imageLoader/createImage.js
@@ -54,11 +54,17 @@ function convertToIntPixelData(floatPixelData) {
  * can transfer array buffers but not typed arrays
  * @param imageFrame
  */
-function setPixelDataType(imageFrame) {
+function setPixelDataType(imageFrame, preScale) {
+  const isScaled = preScale?.scaled;
+  const scalingParmeters = preScale?.scalingParameters;
+  const rescaleSlope = scalingParmeters?.rescaleSlope;
+  const rescaleIntercept = scalingParmeters?.rescaleIntercept;
+  const isNegative = rescaleSlope < 0 || rescaleIntercept < 0;
+
   if (imageFrame.bitsAllocated === 32) {
     imageFrame.pixelData = new Float32Array(imageFrame.pixelData);
   } else if (imageFrame.bitsAllocated === 16) {
-    if (imageFrame.pixelRepresentation === 0) {
+    if (imageFrame.pixelRepresentation === 0 && !(isScaled && isNegative)) {
       imageFrame.pixelData = new Uint16Array(imageFrame.pixelData);
     } else {
       imageFrame.pixelData = new Int16Array(imageFrame.pixelData);
@@ -219,7 +225,7 @@ function createImage(imageId, pixelData, transferSyntax, options = {}) {
       }
 
       if (!alreadyTyped) {
-        setPixelDataType(imageFrame);
+        setPixelDataType(imageFrame, imageFrame.preScale);
       }
 
       const imagePlaneModule =