fix(MetadataProvider): Correctly assign imageId for multiframe images and remove unused frame information retrieval method (#5965)

tests/utils/getViewportCanvasStats.ts

@@ -0,0 +1,77 @@
+import { Page } from '@playwright/test';
+
+export type ViewportCanvasStats = {
+  width: number;
+  height: number;
+  /** Fraction of sampled pixels whose luminance is above the black cutoff (0-1). */
+  nonBlackRatio: number;
+  /** Order-sensitive digest of the sampled pixels; differs when the rendered frame differs. */
+  digest: number;
+};
+
+type GetViewportCanvasStatsParams = {
+  page: Page;
+  /** Cornerstone viewport id; the single-viewport default layout uses 'default'. */
+  viewportId?: string;
+};
+
+/**
+ * Reads the pixels currently painted on a viewport's on-screen canvas and
+ * returns aggregate stats. This asserts real rendered output (unlike a
+ * services-state read) without a screenshot baseline: `nonBlackRatio` catches
+ * blank/black viewports and `digest` catches a viewport stuck on a previous
+ * frame after navigation.
+ */
+export const getViewportCanvasStats = async ({
+  page,
+  viewportId = 'default',
+}: GetViewportCanvasStatsParams): Promise<ViewportCanvasStats> => {
+  return page.evaluate(
+    ({ services, viewportId }: withTestTypes<{ viewportId: string }>) => {
+      const { cornerstoneViewportService } = services;
+      const viewport = cornerstoneViewportService.getCornerstoneViewport(viewportId) as any;
+      if (!viewport) {
+        throw new Error(`getViewportCanvasStats: no cornerstone viewport with id "${viewportId}"`);
+      }
+
+      const sourceCanvas = viewport.getCanvas() as HTMLCanvasElement;
+      const { width, height } = sourceCanvas;
+      if (!width || !height) {
+        throw new Error('getViewportCanvasStats: viewport canvas has zero size');
+      }
+
+      // Copy onto a plain 2d canvas so pixels are readable regardless of the
+      // source canvas context type.
+      const copy = document.createElement('canvas');
+      copy.width = width;
+      copy.height = height;
+      const ctx = copy.getContext('2d');
+      ctx.drawImage(sourceCanvas, 0, 0);
+      const { data } = ctx.getImageData(0, 0, width, height);
+
+      const blackCutoff = 16; // 0-255 luminance below this counts as black
+      const sampleStride = 4; // sample every 4th pixel to keep this fast
+      let sampled = 0;
+      let nonBlack = 0;
+      let digest = 0;
+
+      for (let i = 0; i < data.length; i += 4 * sampleStride) {
+        const luminance = 0.2126 * data[i] + 0.7152 * data[i + 1] + 0.0722 * data[i + 2];
+        sampled += 1;
+        if (luminance > blackCutoff) {
+          nonBlack += 1;
+        }
+        // FNV-style rolling hash over the sampled luminance values
+        digest = (Math.imul(digest ^ Math.round(luminance), 16777619) >>> 0) as number;
+      }
+
+      return {
+        width,
+        height,
+        nonBlackRatio: sampled ? nonBlack / sampled : 0,
+        digest,
+      };
+    },
+    { viewportId, services: await page.evaluateHandle('window.services') }
+  );
+};

tests/utils/index.ts

@@ -25,6 +25,7 @@ import { scrollVolumeViewport } from './scrollVolumeViewport';
 import { attemptAction } from './attemptAction';
 import { addLengthMeasurement } from './addLengthMeasurement';
 import { getSvgAttribute } from './getSvgAttribute';
+import { getViewportCanvasStats } from './getViewportCanvasStats';
 import { navigateWithViewportArrow } from './navigateWithViewportArrow';
 import { contourShowOnlyNthSegment } from './contourShowOnlyNthSegment';
 import { visitStudyAndHydrate } from './visitStudyAndHydrate';
@@ -62,6 +63,7 @@ export {
   addLengthMeasurement,
   subscribeToMeasurementAdded,
   getSvgAttribute,
+  getViewportCanvasStats,
   navigateWithViewportArrow,
   contourShowOnlyNthSegment,
   visitStudyAndHydrate,