Android Camera Set setMetering(Camera.Parameters parameters)

Description

set Metering

License

Apache License

Declaration

public static void setMetering(Camera.Parameters parameters) 

Method Source Code

//package com.java2s;
/*//from   www .jav  a  2  s  .c o  m
 * Copyright (C) 2014 ZXing authors
 *
 * 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.
 */

import android.graphics.Rect;
import android.hardware.Camera;

import android.util.Log;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;

import java.util.Iterator;
import java.util.List;

public class Main {
    private static final String TAG = "CameraConfiguration";
    private static final int AREA_PER_1000 = 400;

    public static void setMetering(Camera.Parameters parameters) {
        if (parameters.getMaxNumMeteringAreas() > 0) {
            Log.i(TAG,
                    "Old metering areas: " + parameters.getMeteringAreas());
            List<Camera.Area> middleArea = buildMiddleArea(AREA_PER_1000);
            Log.i(TAG, "Setting metering area to : " + toString(middleArea));
            parameters.setMeteringAreas(middleArea);
        } else {
            Log.i(TAG, "Device does not support metering areas");
        }
    }

    private static List<Camera.Area> buildMiddleArea(int areaPer1000) {
        return Collections.singletonList(new Camera.Area(new Rect(
                -areaPer1000, -areaPer1000, areaPer1000, areaPer1000), 1));
    }

    private static String toString(Collection<int[]> arrays) {
        if (arrays == null || arrays.isEmpty()) {
            return "[]";
        }
        StringBuilder buffer = new StringBuilder();
        buffer.append('[');
        Iterator<int[]> it = arrays.iterator();
        while (it.hasNext()) {
            buffer.append(Arrays.toString(it.next()));
            if (it.hasNext()) {
                buffer.append(", ");
            }
        }
        buffer.append(']');
        return buffer.toString();
    }

    private static String toString(Iterable<Camera.Area> areas) {
        if (areas == null) {
            return null;
        }
        StringBuilder result = new StringBuilder();
        for (Camera.Area area : areas) {
            result.append(area.rect).append(':').append(area.weight)
                    .append(' ');
        }
        return result.toString();
    }
}

Related

1. setBestPreviewFPS(Camera.Parameters parameters, int minFPS, int maxFPS)
2. setCameraDisplayOrientation(Context mContext, int cameraId, Camera camera)
3. setFocus(Camera.Parameters parameters, boolean autoFocus, boolean disableContinuous, boolean safeMode)
4. setFocusArea(Camera.Parameters parameters)
5. setInvertColor(Camera.Parameters parameters)
6. setTorch(Camera.Parameters parameters, boolean on)
7. setVideoStabilization(Camera.Parameters parameters)
8. setZoom(Camera.Parameters parameters, double targetZoomRatio)
9. getBackId()