Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2013 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.hardware.Camera;

import java.util.List;

public class Main {
    /**
     * Find the preview size that best fit the prescribed one.
     */
    public static Camera.Size getOptimalPreviewSize(Camera.Parameters params, int w, int h) {
        List<Camera.Size> sizes = params.getSupportedPreviewSizes();

        // Use a very small tolerance because we want an exact match.
        final double ASPECT_TOLERANCE = 0.1;
        double targetRatio = (double) w / h;
        if (sizes == null)
            return null;

        Camera.Size optimalSize = null;

        // Start with max value and refine as we iterate over available preview sizes. This is the
        // minimum difference between view and camera height.
        double minDiff = Double.MAX_VALUE;

        // Target view height
        int targetHeight = h;

        // Try to find a preview size that matches aspect ratio and the target view size.
        // Iterate over all available sizes and pick the largest size that can fit in the view and
        // still maintain the aspect ratio.
        for (Camera.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 preview size that matches the aspect ratio, ignore the requirement
        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Camera.Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }

        return optimalSize;
    }
}