Added non-uniform scaling for spatial sampling. (55732c52) · Commits · e / os / android_frameworks_base

core/java/android/gesture/GestureUtilities.java

+65 −40

Original line number	Diff line number	Diff line
		@@ -28,6 +28,9 @@ import static android.gesture.GestureConstants.*;

		final class GestureUtilities {

		private static final float SCALING_THRESHOLD = 0.26f;
		private static final float NONUNIFORM_SCALE = (float) Math.sqrt(2);

		private GestureUtilities() {
		}

		@@ -46,63 +49,82 @@ final class GestureUtilities {
		}
		}

		static float[] spatialSampling(Gesture gesture, int sampleMatrixDimension) {
		static float[] spatialSampling(Gesture gesture, int sampleMatrixDimension,
		boolean uniformScaling) {
		final float targetPatchSize = sampleMatrixDimension - 1; // edge inclusive
		float[] sample = new float[sampleMatrixDimension * sampleMatrixDimension];
		Arrays.fill(sample, 0);

		RectF rect = gesture.getBoundingBox();
		float sx = targetPatchSize / rect.width();
		float sy = targetPatchSize / rect.height();
		final float gestureWidth = rect.width();
		final float gestureHeight = rect.height();
		float sx = targetPatchSize / gestureWidth;
		float sy = targetPatchSize / gestureHeight;

		if (uniformScaling) {
		float scale = sx < sy ? sx : sy;
		sx = scale;
		sy = scale;
		} else {

		float aspectRatio = gestureWidth / gestureHeight;
		if (aspectRatio > 1) {
		aspectRatio = 1 / aspectRatio;
		}
		if (aspectRatio < SCALING_THRESHOLD) {
		float scale = sx < sy ? sx : sy;
		sx = scale;
		sy = scale;
		} else {
		if (sx > sy) {
		float scale = sy * NONUNIFORM_SCALE;
		if (scale < sx) {
		sx = scale;
		}
		} else {
		float scale = sx * NONUNIFORM_SCALE;
		if (scale < sy) {
		sy = scale;
		}
		}
		}
		}
		float preDx = -rect.centerX();
		float preDy = -rect.centerY();
		float postDx = targetPatchSize / 2;
		float postDy = targetPatchSize / 2;

		final ArrayList<GestureStroke> strokes = gesture.getStrokes();
		final int count = strokes.size();

		int size;
		float xpos;
		float ypos;

		for (int index = 0; index < count; index++) {
		final GestureStroke stroke = strokes.get(index);
		float[] strokepoints = stroke.points;
		size = strokepoints.length;

		final float[] pts = new float[size];

		for (int i = 0; i < size; i += 2) {
		pts[i] = (strokepoints[i] + preDx) * scale + postDx;
		pts[i + 1] = (strokepoints[i + 1] + preDy) * scale + postDy;
		pts[i] = (strokepoints[i] + preDx) * sx + postDx;
		pts[i + 1] = (strokepoints[i + 1] + preDy) * sy + postDy;
		}

		float segmentEndX = -1;
		float segmentEndY = -1;

		for (int i = 0; i < size; i += 2) {

		float segmentStartX = pts[i] < 0 ? 0 : pts[i];
		float segmentStartY = pts[i + 1] < 0 ? 0 : pts[i + 1];

		if (segmentStartX > targetPatchSize) {
		segmentStartX = targetPatchSize;
		}

		if (segmentStartY > targetPatchSize) {
		segmentStartY = targetPatchSize;
		}

		plot(segmentStartX, segmentStartY, sample, sampleMatrixDimension);

		if (segmentEndX != -1) {
		// evaluate horizontally
		if (segmentEndX > segmentStartX) {
		xpos = (float) Math.ceil(segmentStartX);
		float slope = (segmentEndY - segmentStartY) / (segmentEndX - segmentStartX);
		float slope = (segmentEndY - segmentStartY) /
		(segmentEndX - segmentStartX);
		while (xpos < segmentEndX) {
		ypos = slope * (xpos - segmentStartX) + segmentStartY;
		plot(xpos, ypos, sample, sampleMatrixDimension);
		@@ -110,18 +132,19 @@ final class GestureUtilities {
		}
		} else if (segmentEndX < segmentStartX){
		xpos = (float) Math.ceil(segmentEndX);
		float slope = (segmentEndY - segmentStartY) / (segmentEndX - segmentStartX);
		float slope = (segmentEndY - segmentStartY) /
		(segmentEndX - segmentStartX);
		while (xpos < segmentStartX) {
		ypos = slope * (xpos - segmentStartX) + segmentStartY;
		plot(xpos, ypos, sample, sampleMatrixDimension);
		xpos++;
		}
		}

		// evaluating vertically
		if (segmentEndY > segmentStartY) {
		ypos = (float) Math.ceil(segmentStartY);
		float invertSlope = (segmentEndX - segmentStartX) / (segmentEndY - segmentStartY);
		float invertSlope = (segmentEndX - segmentStartX) /
		(segmentEndY - segmentStartY);
		while (ypos < segmentEndY) {
		xpos = invertSlope * (ypos - segmentStartY) + segmentStartX;
		plot(xpos, ypos, sample, sampleMatrixDimension);
		@@ -129,7 +152,8 @@ final class GestureUtilities {
		}
		} else if (segmentEndY < segmentStartY) {
		ypos = (float) Math.ceil(segmentEndY);
		float invertSlope = (segmentEndX - segmentStartX) / (segmentEndY - segmentStartY);
		float invertSlope = (segmentEndX - segmentStartX) /
		(segmentEndY - segmentStartY);
		while (ypos < segmentStartY) {
		xpos = invertSlope * (ypos - segmentStartY) + segmentStartX;
		plot(xpos, ypos, sample, sampleMatrixDimension);
		@@ -137,13 +161,10 @@ final class GestureUtilities {
		}
		}
		}

		segmentEndX = segmentStartX;
		segmentEndY = segmentStartY;
		}
		}


		return sample;
		}

		@@ -162,40 +183,44 @@ final class GestureUtilities {
		sample[index] = 1;
		}
		} else {
		double topLeft = Math.sqrt(Math.pow(xFloor - x, 2) + Math.pow(yFloor - y, 2));
		double topRight = Math.sqrt(Math.pow(xCeiling - x, 2) + Math.pow(yFloor - y, 2));
		double btmLeft = Math.sqrt(Math.pow(xFloor - x, 2) + Math.pow(yCeiling - y, 2));
		double btmRight = Math.sqrt(Math.pow(xCeiling - x, 2) + Math.pow(yCeiling - y, 2));
		double sum = topLeft + topRight + btmLeft + btmRight;

		double value = topLeft / sum;
		final double xFloorSq = Math.pow(xFloor - x, 2);
		final double yFloorSq = Math.pow(yFloor - y, 2);
		final double xCeilingSq = Math.pow(xCeiling - x, 2);
		final double yCeilingSq = Math.pow(yCeiling - y, 2);
		float topLeft = (float) Math.sqrt(xFloorSq + yFloorSq);
		float topRight = (float) Math.sqrt(xCeilingSq + yFloorSq);
		float btmLeft = (float) Math.sqrt(xFloorSq + yCeilingSq);
		float btmRight = (float) Math.sqrt(xCeilingSq + yCeilingSq);
		float sum = topLeft + topRight + btmLeft + btmRight;

		float value = topLeft / sum;
		int index = yFloor * sampleSize + xFloor;
		if (value > sample[index]){
		sample[index] = (float) value;
		sample[index] = value;
		}

		value = topRight / sum;
		index = yFloor * sampleSize + xCeiling;
		if (value > sample[index]){
		sample[index] = (float) value;
		sample[index] = value;
		}

		value = btmLeft / sum;
		index = yCeiling * sampleSize + xFloor;
		if (value > sample[index]){
		sample[index] = (float) value;
		sample[index] = value;
		}

		value = btmRight / sum;
		index = yCeiling * sampleSize + xCeiling;
		if (value > sample[index]){
		sample[index] = (float) value;
		sample[index] = value;
		}
		}
		}

		/**
		* Featurize a stroke into a vector of a given number of elements
		* Featurizes a stroke into a vector of a given number of elements
		*
		* @param stroke
		* @param sampleSize

core/java/android/gesture/Instance.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -84,7 +84,7 @@ class Instance {
		}

		private static float[] spatialSampler(Gesture gesture) {
		return GestureUtilities.spatialSampling(gesture, PATCH_SAMPLE_SIZE);
		return GestureUtilities.spatialSampling(gesture, PATCH_SAMPLE_SIZE, false);
		}

		private static float[] temporalSampler(int orientationType, Gesture gesture) {