Android Camera Set setZoom(Camera.Parameters parameters, double targetZoomRatio)

Description

set Zoom

License

Apache License

Declaration

public static void setZoom(Camera.Parameters parameters,
            double targetZoomRatio) 

Method Source Code

//package com.java2s;
/*/*w w  w. ja v  a 2s  . com*/
 * 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.hardware.Camera;

import android.util.Log;

import java.util.List;

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

    public static void setZoom(Camera.Parameters parameters,
            double targetZoomRatio) {
        if (parameters.isZoomSupported()) {
            Integer zoom = indexOfClosestZoom(parameters, targetZoomRatio);
            if (zoom == null) {
                return;
            }
            if (parameters.getZoom() == zoom) {
                Log.i(TAG, "Zoom is already set to " + zoom);
            } else {
                Log.i(TAG, "Setting zoom to " + zoom);
                parameters.setZoom(zoom);
            }
        } else {
            Log.i(TAG, "Zoom is not supported");
        }
    }

    private static Integer indexOfClosestZoom(Camera.Parameters parameters,
            double targetZoomRatio) {
        List<Integer> ratios = parameters.getZoomRatios();
        Log.i(TAG, "Zoom ratios: " + ratios);
        int maxZoom = parameters.getMaxZoom();
        if (ratios == null || ratios.isEmpty()
                || ratios.size() != maxZoom + 1) {
            Log.w(TAG, "Invalid zoom ratios!");
            return null;
        }
        double target100 = 100.0 * targetZoomRatio;
        double smallestDiff = Double.POSITIVE_INFINITY;
        int closestIndex = 0;
        for (int i = 0; i < ratios.size(); i++) {
            double diff = Math.abs(ratios.get(i) - target100);
            if (diff < smallestDiff) {
                smallestDiff = diff;
                closestIndex = i;
            }
        }
        Log.i(TAG, "Chose zoom ratio of "
                + (ratios.get(closestIndex) / 100.0));
        return closestIndex;
    }
}

Related

1. setFocusArea(Camera.Parameters parameters)
2. setInvertColor(Camera.Parameters parameters)
3. setMetering(Camera.Parameters parameters)
4. setTorch(Camera.Parameters parameters, boolean on)
5. setVideoStabilization(Camera.Parameters parameters)
6. getBackId()
7. adjustCamera(Context context, Camera camera)