[FaceGaze] Exclude blink when detecting eye squint left/right

* Add logic to GestureDetector to ignore certain instances of
gestures if certain MediapipeFacialGestures are detected at
the same time at a confidence of > 0.5.
* For EYE_SQUINT_LEFT and EYE_SQUINT_RIGHT, if an eye squint
or blink on the other side is also detected and at > 0.5,
do not register the gesture as the user is likely blinking
involuntarily.
* Add test to check that blinking will not trigger
EYE_SQUINT_LEFT or EYE_SQUINT_RIGHT.

AX-Relnotes: N/A
Fixed: 374774499
Change-Id: I937588c4ac1246e428b86b430a77fa58aa4c6d79
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5962467
Reviewed-by: Akihiro Ota <akihiroota@chromium.org>
Commit-Queue: Amanda Lin Dietz <aldietz@google.com>
Cr-Commit-Position: refs/heads/main@{#1374180}

chrome/browser/resources/chromeos/accessibility/accessibility_common/facegaze/facegaze_test.js

@@ -2221,3 +2221,92 @@ AX_TEST_F('FaceGazeTest', 'GesturesDisabledDuringDictation', async function() {
           .addGestureWithConfidence(MediapipeFacialGesture.JAW_OPEN, 0.9));
   assertEquals(result.macros.length, 2);
 });
+
+AX_TEST_F('FaceGazeTest', 'BlinkDoesNotTriggerEyeSquint', async function() {
+  const gestureToMacroName =
+      new Map()
+          .set(FacialGesture.EYES_BLINK, MacroName.MOUSE_CLICK_LEFT)
+          .set(FacialGesture.EYE_SQUINT_LEFT, MacroName.TOGGLE_SCROLL_MODE)
+          .set(FacialGesture.EYE_SQUINT_RIGHT, MacroName.TOGGLE_FACEGAZE);
+  const gestureToConfidence = new Map()
+                                  .set(FacialGesture.EYES_BLINK, 0.6)
+                                  .set(FacialGesture.EYE_SQUINT_LEFT, 0.6)
+                                  .set(FacialGesture.EYE_SQUINT_RIGHT, 0.6);
+  const config = new Config()
+                     .withMouseLocation({x: 600, y: 400})
+                     .withGestureToMacroName(gestureToMacroName)
+                     .withGestureToConfidence(gestureToConfidence)
+                     .withRepeatDelayMs(0);
+  await this.configureFaceGaze(config);
+
+  const gestureHandler = this.getFaceGaze().gestureHandler_;
+
+  // If eye squint on one side occurs at same time as a blink or squint on the
+  // wrong side, then the gesture should not register as an eye squint on the
+  // intended side.
+  let result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.9)
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_BLINK_LEFT, 0.6)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_BLINK_RIGHT, 0.6));
+  assertEquals(result.macros.length, 1);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.9)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.6));
+  assertEquals(result.macros.length, 0);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.9)
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_BLINK_LEFT, 0.6)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_BLINK_RIGHT, 0.6));
+  assertEquals(result.macros.length, 1);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.9)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.6));
+  assertEquals(result.macros.length, 0);
+
+  // Low confidence levels of blink or squint on the wrong side should register
+  // as a squint on the intended side.
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.9)
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_BLINK_LEFT, 0.3)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_BLINK_RIGHT, 0.3));
+  assertEquals(result.macros.length, 1);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.9)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.3));
+  assertEquals(result.macros.length, 1);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.9)
+          .addGestureWithConfidence(MediapipeFacialGesture.EYE_BLINK_LEFT, 0.3)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_BLINK_RIGHT, 0.3));
+  assertEquals(result.macros.length, 1);
+
+  result = gestureHandler.detectMacros(
+      new MockFaceLandmarkerResult()
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_RIGHT, 0.9)
+          .addGestureWithConfidence(
+              MediapipeFacialGesture.EYE_SQUINT_LEFT, 0.3));
+  assertEquals(result.macros.length, 1);
+});

chrome/browser/resources/chromeos/accessibility/accessibility_common/facegaze/gesture_detector.ts

@@ -110,6 +110,28 @@ export const FacialGesturesToMediapipeGestures = new Map([
   ],
 ]);
 
+/**
+ * Mapping of gestures supported by FaceGaze to mediapipe gestures that should
+ * not be present in order to confidently trigger the supported gesture, so as
+ * to reduce triggering gestures with involuntary facial movement like blinking.
+ */
+export const FacialGesturesToExcludedMediapipeGestures = new Map([
+  [
+    FacialGesture.EYE_SQUINT_LEFT,
+    [
+      MediapipeFacialGesture.EYE_BLINK_RIGHT,
+      MediapipeFacialGesture.EYE_SQUINT_RIGHT,
+    ]
+  ],
+  [
+    FacialGesture.EYE_SQUINT_RIGHT,
+    [
+      MediapipeFacialGesture.EYE_BLINK_LEFT,
+      MediapipeFacialGesture.EYE_SQUINT_LEFT,
+    ]
+  ],
+]);
+
 export class GestureDetector {
   private static mediapipeFacialGestureSet_ =
       new Set(Object.values(MediapipeFacialGesture));
@@ -174,6 +196,26 @@ export class GestureDetector {
         continue;
       }
 
+      let hasExcludedGesture = false;
+      const excludedGestures =
+          FacialGesturesToExcludedMediapipeGestures.get(faceGazeGesture);
+
+      // Check for gestures that should not be present in order to confidently
+      // register this gesture.
+      if (excludedGestures) {
+        for (const excludedGesture of excludedGestures) {
+          if (recognizedGestures.has(excludedGesture) &&
+              recognizedGestures.get(excludedGesture) >
+                  GestureDetector.EXCLUDED_GESTURE_THRESHOLD) {
+            hasExcludedGesture = true;
+          }
+        }
+      }
+
+      if (hasExcludedGesture) {
+        continue;
+      }
+
       // For gestures detected with a confidence value over a threshold value of
       // 1, add the gesture and confidence value to the array of information
       // that will be sent to settings.
@@ -199,6 +241,19 @@ export class GestureDetector {
   }
 }
 
+export namespace GestureDetector {
+  /**
+   * The confidence level at which a detected gesture B should disqualify a
+   * different gesture A from being triggered if A relies on B not being
+   * present. For example, if EYE_SQUINT_LEFT is detected but EYE_SQUINT_RIGHT
+   * is also detected at confidence > EXCLUDED_GESTURE_THRESHOLD, then the
+   * gesture was likely involuntary blinking and EYE_SQUINT_LEFT should not be
+   * triggered. A confidence level of 0.5 seems to be the approximate confidence
+   * that occurs for most involuntary blinking.
+   */
+  export const EXCLUDED_GESTURE_THRESHOLD = 0.5;
+}
+
 TestImportManager.exportForTesting(
     GestureDetector, ['FacialGesture', FacialGesture],
     ['MediapipeFacialGesture', MediapipeFacialGesture],