added Classifiers and Evaluators (68d0c9b1) · Commits · e / os / android_frameworks_base

packages/SystemUI/src/com/android/systemui/classifier/AccelerationClassifier.java

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		/*
		* Copyright (C) 2015 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License
		*/

		package com.android.systemui.classifier;

		import android.view.MotionEvent;

		import java.util.HashMap;

		/**
		* A classifier which looks at the speed and distance between successive points of a Stroke.
		* It looks at two consecutive speeds between two points and calculates the ratio between them.
		* The final result is the maximum of these values. It does the same for distances. If some speed
		* or distance is equal to zero then the ratio between this and the next part is not calculated. To
		* the duration of each part there is added one nanosecond so that it is always possible to
		* calculate the speed of a part.
		*/
		public class AccelerationClassifier extends StrokeClassifier {
		private final HashMap<Stroke, Data> mStrokeMap = new HashMap<>();

		public AccelerationClassifier(ClassifierData classifierData) {
		mClassifierData = classifierData;
		}

		@Override
		public void onTouchEvent(MotionEvent event) {
		int action = event.getActionMasked();

		if (action == MotionEvent.ACTION_DOWN) {
		mStrokeMap.clear();
		}

		for (int i = 0; i < event.getPointerCount(); i++) {
		Stroke stroke = mClassifierData.getStroke(event.getPointerId(i));
		Point point = stroke.getPoints().get(stroke.getPoints().size() - 1);
		if (mStrokeMap.get(stroke) == null) {
		mStrokeMap.put(stroke, new Data(point));
		} else {
		mStrokeMap.get(stroke).addPoint(point);
		}
		}
		}

		@Override
		public float getFalseTouchEvaluation(int type, Stroke stroke) {
		Data data = mStrokeMap.get(stroke);
		return SpeedRatioEvaluator.evaluate(data.maxSpeedRatio)
		+ DistanceRatioEvaluator.evaluate(data.maxDistanceRatio);
		}

		private static class Data {
		public Point previousPoint;
		public float previousSpeed;
		public float previousDistance;
		public float maxSpeedRatio;
		public float maxDistanceRatio;

		public Data(Point point) {
		previousPoint = point;
		previousSpeed = previousDistance = 0.0f;
		maxDistanceRatio = maxSpeedRatio = 0.0f;
		}

		public void addPoint(Point point) {
		float distance = previousPoint.dist(point);
		float duration = (float) (point.timeOffsetNano - previousPoint.timeOffsetNano + 1);
		float speed = distance / duration;
		if (previousDistance != 0.0f) {
		maxDistanceRatio = Math.max(maxDistanceRatio, distance / previousDistance);
		}

		if (previousSpeed != 0.0f) {
		maxSpeedRatio = Math.max(maxSpeedRatio, speed / previousSpeed);
		}

		previousDistance = distance;
		previousSpeed = speed;
		previousPoint = point;
		}
		}
		}
		No newline at end of file

packages/SystemUI/src/com/android/systemui/classifier/AnglesVarianceClassifier.java

+43 −22

Original line number	Diff line number	Diff line
		@@ -29,10 +29,15 @@ import java.util.List;
		* For each stroke it keeps its last three points. If some successive points are the same, it
		* ignores the repetitions. If a new point is added, the classifier calculates the angle between
		* the last three points. After that, it calculates the difference between this angle and the
		* previously calculated angle. The return value of the classifier is the variance of the
		* differences from a stroke. To the differences there is artificially added value 0.0 and the
		* difference between the first angle and PI (angles are in radians). It helps with strokes which
		* have few points and punishes more strokes which are not smooth.
		* previously calculated angle. Then it calculates the variance of the differences from a stroke.
		* To the differences there is artificially added value 0.0 and the difference between the first
		* angle and PI (angles are in radians). It helps with strokes which have few points and punishes
		* more strokes which are not smooth. This classifier also tries to split the stroke into two parts
		* int the place in which the biggest angle is. It calculates the angle variance of the two parts
		* and sums them up. The reason the classifier is doing this, is because some human swipes at the
		* beginning go for a moment in one direction and then they rapidly change direction for the rest
		* of the stroke (like a tick). The final result is the minimum of angle variance of the whole
		* stroke and the sum of angle variances of the two parts split up.
		*/
		public class AnglesVarianceClassifier extends StrokeClassifier {
		private HashMap<Stroke, Data> mStrokeMap = new HashMap<>();
		@@ -61,21 +66,28 @@ public class AnglesVarianceClassifier extends StrokeClassifier {

		@Override
		public float getFalseTouchEvaluation(int type, Stroke stroke) {
		return mStrokeMap.get(stroke).getAnglesVariance();
		return AnglesVarianceEvaluator.evaluate(mStrokeMap.get(stroke).getAnglesVariance());
		}

		private class Data {
		private static class Data {
		private List<Point> mLastThreePoints = new ArrayList<>();
		private float mFirstAngleVariance;
		private float mPreviousAngle;
		private float mBiggestAngle;
		private float mSumSquares;
		private float mSecondSumSquares;
		private float mSum;
		private float mSecondSum;
		private float mCount;
		private float mSecondCount;

		public Data() {
		mFirstAngleVariance = 0.0f;
		mPreviousAngle = (float) Math.PI;
		mSumSquares = 0.0f;
		mSum = 0.0f;
		mCount = 1.0f;
		mBiggestAngle = 0.0f;
		mSumSquares = mSecondSumSquares = 0.0f;
		mSum = mSecondSum = 0.0f;
		mCount = mSecondCount = 1.0f;
		}

		public void addPoint(Point point) {
		@@ -87,10 +99,26 @@ public class AnglesVarianceClassifier extends StrokeClassifier {
		if (mLastThreePoints.size() == 4) {
		mLastThreePoints.remove(0);

		float angle = getAngle(mLastThreePoints.get(0), mLastThreePoints.get(1),
		float angle = mLastThreePoints.get(1).getAngle(mLastThreePoints.get(0),
		mLastThreePoints.get(2));

		float difference = angle - mPreviousAngle;

		// If this is the biggest angle of the stroke so then we save the value of
		// the angle variance so far and start to count the values for the angle
		// variance of the second part.
		if (mBiggestAngle < angle) {
		mBiggestAngle = angle;
		mFirstAngleVariance = getAnglesVariance(mSumSquares, mSum, mCount);
		mSecondSumSquares = 0.0f;
		mSecondSum = 0.0f;
		mSecondCount = 1.0f;
		} else {
		mSecondSum += difference;
		mSecondSumSquares += difference * difference;
		mSecondCount += 1.0;
		}

		mSum += difference;
		mSumSquares += difference * difference;
		mCount += 1.0;
		@@ -99,21 +127,14 @@ public class AnglesVarianceClassifier extends StrokeClassifier {
		}
		}

		private float getAngle(Point a, Point b, Point c) {
		float dist1 = a.dist(b);
		float dist2 = b.dist(c);
		float crossProduct = b.crossProduct(a, c);
		float dotProduct = b.dotProduct(a, c);
		float cos = Math.min(1.0f, Math.max(-1.0f, dotProduct / dist1 / dist2));
		float angle = (float) Math.acos(cos);
		if (crossProduct < 0.0) {
		angle = 2.0f * (float) Math.PI - angle;
		}
		return angle;
		public float getAnglesVariance(float sumSquares, float sum, float count) {
		return sumSquares / count - (sum / count) * (sum / count);
		}

		public float getAnglesVariance() {
		return mSumSquares / mCount - (mSum / mCount) * (mSum / mCount);
		return Math.min(getAnglesVariance(mSumSquares, mSum, mCount),
		mFirstAngleVariance + getAnglesVariance(mSecondSumSquares, mSecondSum,
		mSecondCount));
		}
		}
		}
		No newline at end of file

packages/SystemUI/src/com/android/systemui/classifier/AnglesVarianceEvaluator.java

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+30 −0

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		/*
		* Copyright (C) 2015 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License
		*/

		package com.android.systemui.classifier;

		public class AnglesVarianceEvaluator {
		public static float evaluate(float value) {
		float evaluation = 0.0f;
		if (value > 0.05) evaluation++;
		if (value > 0.10) evaluation++;
		if (value > 0.20) evaluation++;
		if (value > 0.40) evaluation++;
		if (value > 0.80) evaluation++;
		if (value > 1.50) evaluation++;
		return evaluation;
		}
		}

packages/SystemUI/src/com/android/systemui/classifier/ClassifierData.java

+6 −2

Original line number	Diff line number	Diff line
		@@ -28,8 +28,12 @@ import java.util.ArrayList;
		public class ClassifierData {
		private SparseArray<Stroke> mCurrentStrokes = new SparseArray<>();
		private ArrayList<Stroke> mEndingStrokes = new ArrayList<>();
		private float mXdpi;
		private float mYdpi;

		public ClassifierData() {
		public ClassifierData(float xdpi, float ydpi) {
		mXdpi = xdpi;
		mYdpi = ydpi;
		}

		public void update(MotionEvent event) {
		@@ -42,7 +46,7 @@ public class ClassifierData {
		for (int i = 0; i < event.getPointerCount(); i++) {
		int id = event.getPointerId(i);
		if (mCurrentStrokes.get(id) == null) {
		mCurrentStrokes.put(id, new Stroke(event.getEventTimeNano()));
		mCurrentStrokes.put(id, new Stroke(event.getEventTimeNano(), mXdpi, mYdpi));
		}
		mCurrentStrokes.get(id).addPoint(event.getX(i), event.getY(i),
		event.getEventTimeNano());

packages/SystemUI/src/com/android/systemui/classifier/DistanceRatioEvaluator.java

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+29 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2015 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License
		*/

		package com.android.systemui.classifier;

		public class DistanceRatioEvaluator {
		public static float evaluate(float value) {
		float evaluation = 0.0f;
		if (value <= 1.0) evaluation++;
		if (value <= 0.5) evaluation++;
		if (value > 4.0) evaluation++;
		if (value > 7.0) evaluation++;
		if (value > 14.0) evaluation++;
		return evaluation;
		}
		}