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/* * Copyright (C) 2014 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 android.hardware.camera2.params; import android.util.Size; import static com.android.internal.util.Preconditions.*; import android.graphics.Point; import android.graphics.Rect; import android.hardware.camera2.CameraCharacteristics; import android.hardware.camera2.CaptureRequest; import android.hardware.camera2.utils.HashCodeHelpers; /** * An immutable class to represent a rectangle {@code (x, y, width, height)} with an additional * weight component. * <p> * The rectangle is defined to be inclusive of the specified coordinates. * </p> * <p> * When used with a {@link CaptureRequest}, the coordinate system is based on the active pixel * array, with {@code (0,0)} being the top-left pixel in the * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE active pixel array}, and * {@code (android.sensor.info.activeArraySize.width - 1, * android.sensor.info.activeArraySize.height - 1)} being the bottom-right pixel in the active pixel * array. * </p> * <p> * The weight must range from {@value #METERING_WEIGHT_MIN} to {@value #METERING_WEIGHT_MAX} * inclusively, and represents a weight for every pixel in the area. This means that a large * metering area with the same weight as a smaller area will have more effect in the metering * result. Metering areas can partially overlap and the camera device will add the weights in the * overlap rectangle. * </p> * <p> * If all rectangles have 0 weight, then no specific metering area needs to be used by the camera * device. If the metering rectangle is outside the used android.scaler.cropRegion returned in * capture result metadata, the camera device will ignore the sections outside the rectangle and * output the used sections in the result metadata. * </p> */ public final class MeteringRectangle { /** * The minimum value of valid metering weight. */ public static final int METERING_WEIGHT_MIN = 0; /** * The maximum value of valid metering weight. */ public static final int METERING_WEIGHT_MAX = 1000; /** * Weights set to this value will cause the camera device to ignore this rectangle. * If all metering rectangles are weighed with 0, the camera device will choose its own metering * rectangles. */ public static final int METERING_WEIGHT_DONT_CARE = 0; private final int mX; private final int mY; private final int mWidth; private final int mHeight; private final int mWeight; /** * Create a new metering rectangle. * * @param x coordinate >= 0 * @param y coordinate >= 0 * @param width width >= 0 * @param height height >= 0 * @param meteringWeight weight between {@value #METERING_WEIGHT_MIN} and * {@value #METERING_WEIGHT_MAX} inclusively * @throws IllegalArgumentException if any of the parameters were negative */ public MeteringRectangle(int x, int y, int width, int height, int meteringWeight) { mX = checkArgumentNonnegative(x, "x must be nonnegative"); mY = checkArgumentNonnegative(y, "y must be nonnegative"); mWidth = checkArgumentNonnegative(width, "width must be nonnegative"); mHeight = checkArgumentNonnegative(height, "height must be nonnegative"); mWeight = checkArgumentInRange(meteringWeight, METERING_WEIGHT_MIN, METERING_WEIGHT_MAX, "meteringWeight"); } /** * Create a new metering rectangle. * * <p>The point {@code xy}'s data is copied; the reference is not retained.</p> * * @param xy a non-{@code null} {@link Point} with both x,y >= 0 * @param dimensions a non-{@code null} {@link android.util.Size Size} with width, height >= 0 * @param meteringWeight weight >= 0 * * @throws IllegalArgumentException if any of the parameters were negative * @throws NullPointerException if any of the arguments were null */ public MeteringRectangle(Point xy, Size dimensions, int meteringWeight) { checkNotNull(xy, "xy must not be null"); checkNotNull(dimensions, "dimensions must not be null"); mX = checkArgumentNonnegative(xy.x, "x must be nonnegative"); mY = checkArgumentNonnegative(xy.y, "y must be nonnegative"); mWidth = checkArgumentNonnegative(dimensions.getWidth(), "width must be nonnegative"); mHeight = checkArgumentNonnegative(dimensions.getHeight(), "height must be nonnegative"); mWeight = checkArgumentNonnegative(meteringWeight, "meteringWeight must be nonnegative"); } /** * Create a new metering rectangle. * * <p>The rectangle data is copied; the reference is not retained.</p> * * @param rect a non-{@code null} rectangle with all x,y,w,h dimensions >= 0 * @param meteringWeight weight >= 0 * * @throws IllegalArgumentException if any of the parameters were negative * @throws NullPointerException if any of the arguments were null */ public MeteringRectangle(Rect rect, int meteringWeight) { checkNotNull(rect, "rect must not be null"); mX = checkArgumentNonnegative(rect.left, "rect.left must be nonnegative"); mY = checkArgumentNonnegative(rect.top, "rect.top must be nonnegative"); mWidth = checkArgumentNonnegative(rect.width(), "rect.width must be nonnegative"); mHeight = checkArgumentNonnegative(rect.height(), "rect.height must be nonnegative"); mWeight = checkArgumentNonnegative(meteringWeight, "meteringWeight must be nonnegative"); } /** * Return the X coordinate of the left side of the rectangle. * * @return x coordinate >= 0 */ public int getX() { return mX; } /** * Return the Y coordinate of the upper side of the rectangle. * * @return y coordinate >= 0 */ public int getY() { return mY; } /** * Return the width of the rectangle. * * @return width >= 0 */ public int getWidth() { return mWidth; } /** * Return the height of the rectangle. * * @return height >= 0 */ public int getHeight() { return mHeight; } /** * Return the metering weight of the rectangle. * * @return weight >= 0 */ public int getMeteringWeight() { return mWeight; } /** * Convenience method to create the upper-left (X,Y) coordinate as a {@link Point}. * * @return a new {@code (x,y)} {@link Point} with both x,y >= 0 */ public Point getUpperLeftPoint() { return new Point(mX, mY); } /** * Convenience method to create the size from this metering rectangle. * * <p>This strips away the X,Y,weight from the rectangle.</p> * * @return a new {@link Size} with non-negative width and height */ public Size getSize() { return new Size(mWidth, mHeight); } /** * Convenience method to create a {@link Rect} from this metering rectangle. * * <p>This strips away the weight from the rectangle.</p> * * @return a new {@link Rect} with non-negative x1, y1, x2, y2 */ public Rect getRect() { return new Rect(mX, mY, mX + mWidth, mY + mHeight); } /** * {@inheritDoc} */ @Override public boolean equals(final Object other) { return other instanceof MeteringRectangle && equals((MeteringRectangle) other); } /** * Compare two metering rectangles to see if they are equal. * * Two weighted rectangles are only considered equal if each of their components * (x, y, width, height, weight) is respectively equal. * * @param other Another MeteringRectangle * * @return {@code true} if the metering rectangles are equal, {@code false} otherwise */ public boolean equals(final MeteringRectangle other) { if (other == null) { return false; } return (mX == other.mX && mY == other.mY && mWidth == other.mWidth && mHeight == other.mHeight && mWeight == other.mWeight); } /** * {@inheritDoc} */ @Override public int hashCode() { return HashCodeHelpers.hashCode(mX, mY, mWidth, mHeight, mWeight); } /** * Return the metering rectangle as a string representation * {@code "(x:%d, y:%d, w:%d, h:%d, wt:%d)"} where each {@code %d} respectively represents * the x, y, width, height, and weight points. * * @return string representation of the metering rectangle */ @Override public String toString() { return String.format("(x:%d, y:%d, w:%d, h:%d, wt:%d)", mX, mY, mWidth, mHeight, mWeight); } }