commit f7663989cfc1f93e577a6f12a1d3c5ffb80df6d6
author Ytai Ben-Tsvi <ytai@google.com> Thu Jan 06 11:26:12 2022 -0800
committer Ytai Ben-Tsvi <ytai@google.com> Mon Jan 10 15:50:45 2022 -0800
tree dfcb94e26c6f109fcaac2878c4996b00ba987215
parent 4cb1e48792db3e92607f9c8b99c10a19a2f0cbed

Force "not still" for the duration of the window after motion

Because of our motion detection heuristic, we have situations when the
state is considered in motion and then back to still before the window
duration elapses (this is because we always compare the samples in the
buffer to the last one). In order to avoid toggling back-and-forth
faster than the window duration, we add a suppression period after
detecting motion.

Test: atest --host libheadtracking-test
Change-Id: Ia85d5699bef1b3313d007193375df4892f3365ac

media/libheadtracking/StillnessDetector-test.cpp

diff --git a/media/libheadtracking/StillnessDetector-test.cpp b/media/libheadtracking/StillnessDetector-test.cpp
index 646496a..02f9d8a 100644
--- a/media/libheadtracking/StillnessDetector-test.cpp
+++ b/media/libheadtracking/StillnessDetector-test.cpp
@@ -85,9 +85,11 @@
     EXPECT_EQ(mDefaultValue, detector.calculate(600));
     detector.setInput(900, withinThreshold);
     EXPECT_EQ(mDefaultValue, detector.calculate(900));
-    detector.setInput(1299, baseline);
-    EXPECT_FALSE(detector.calculate(1299));
-    EXPECT_TRUE(detector.calculate(1300));
+    detector.setInput(1300, baseline);
+    EXPECT_FALSE(detector.calculate(1300));
+    detector.setInput(1500, baseline);
+    EXPECT_FALSE(detector.calculate(1899));
+    EXPECT_TRUE(detector.calculate(1900));
 }
 
 TEST_P(StillnessDetectorTest, NotStillRotation) {
@@ -100,6 +102,7 @@
     const Pose3f withinThreshold =
             baseline * Pose3f(Vector3f(0.3, -0.3, 0), rotateX(0.03) * rotateY(-0.03));
     const Pose3f outsideThreshold = baseline * Pose3f(rotateZ(0.06));
+
     EXPECT_EQ(mDefaultValue, detector.calculate(0));
     detector.setInput(0, baseline);
     EXPECT_EQ(mDefaultValue, detector.calculate(0));
@@ -109,9 +112,32 @@
     EXPECT_EQ(mDefaultValue, detector.calculate(600));
     detector.setInput(900, withinThreshold);
     EXPECT_EQ(mDefaultValue, detector.calculate(900));
-    detector.setInput(1299, baseline);
-    EXPECT_FALSE(detector.calculate(1299));
-    EXPECT_TRUE(detector.calculate(1300));
+    detector.setInput(1300, baseline);
+    EXPECT_FALSE(detector.calculate(1300));
+    detector.setInput(1500, baseline);
+    EXPECT_FALSE(detector.calculate(1899));
+    EXPECT_TRUE(detector.calculate(1900));
+}
+
+TEST_P(StillnessDetectorTest, Suppression) {
+    StillnessDetector detector(Options{.defaultValue = mDefaultValue,
+                                       .windowDuration = 1000,
+                                       .translationalThreshold = 1,
+                                       .rotationalThreshold = 0.05});
+
+    const Pose3f baseline(Vector3f{1, 2, 3}, Quaternionf::UnitRandom());
+    const Pose3f outsideThreshold = baseline * Pose3f(Vector3f(1.1, 0, 0));
+    const Pose3f middlePoint = baseline * Pose3f(Vector3f(0.55, 0, 0));
+
+    detector.setInput(0, baseline);
+    detector.setInput(1000, baseline);
+    EXPECT_TRUE(detector.calculate(1000));
+    detector.setInput(1100, outsideThreshold);
+    EXPECT_FALSE(detector.calculate(1100));
+    detector.setInput(2000, middlePoint);
+    EXPECT_FALSE(detector.calculate(2000));
+    EXPECT_FALSE(detector.calculate(2099));
+    EXPECT_TRUE(detector.calculate(2100));
 }
 
 TEST_P(StillnessDetectorTest, Reset) {