Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2009 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.
 */

import android.app.Activity;

import android.hardware.Camera.Size;

import android.util.Log;
import android.view.Display;

import java.util.List;

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

    public static Size getOptimalPreviewSize(Activity currentActivity, List<Size> sizes, double targetRatio) {
        // Use a very small tolerance because we want an exact match.
        final double ASPECT_TOLERANCE = 0.001;
        if (sizes == null)
            return null;

        Size optimalSize = null;
        double minDiff = Double.MAX_VALUE;

        // Because of bugs of overlay and layout, we sometimes will try to
        // layout the viewfinder in the portrait orientation and thus get the
        // wrong size of mSurfaceView. When we change the preview size, the
        // new overlay will be created before the old one closed, which causes
        // an exception. For now, just get the screen size

        Display display = currentActivity.getWindowManager().getDefaultDisplay();
        int targetHeight = Math.min(display.getHeight(), display.getWidth());

        if (targetHeight <= 0) {
            // We don't know the size of SurfaceView, use screen height
            targetHeight = display.getHeight();
        }

        // Try to find an size match aspect ratio and size
        for (Size size : sizes) {
            double ratio = (double) size.width / size.height;
            if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
                continue;
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }

        // Cannot find the one match the aspect ratio. This should not happen.
        // Ignore the requirement.
        if (optimalSize == null) {
            Log.w(TAG, "No preview size match the aspect ratio");
            minDiff = Double.MAX_VALUE;
            for (Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }
        return optimalSize;
    }
}