get Camera Best Preview Size - Android Camera

Android examples for Camera:Camera Preview

  1. HOME
  2. Android
  3. Camera
  4. Camera Preview

Description

get Camera Best Preview Size

Demo Code


//package com.java2s;
import java.util.ArrayList;
import java.util.List;
import android.hardware.Camera.Size;

public class Main {
    /**//  w ww .ja v a 2  s .  c om
     * 
     * @param width   of the SurfaceView
     * @param height of the SurfaceView
     * @param supportedPreviewSizes   the sizes reflect the orientation of the camera width > height
     * @param aspectTolerance use CameraPreviewSizeHelper.ASPECT_TOLERANCE
     * @return Size  
     */
    public static Size getBestPreviewSize(int width, int height,
            List<Size> supportedPreviewSizes, double aspectTolerance) {

        /*
         * if necessary, changes the values to the orientation of the camera
         * sensor that is always in landscape what means width > height.
         */
        if (width < height) {
            int tmpHeight = height;
            height = width;
            width = tmpHeight;
        }

        double sourceRatio = (double) width / height;
        List<Size> bestSizesOnRatioAndTolerance = new ArrayList<Size>();
        Size bestPreviewSize = null;

        sourceRatio = Math.abs(sourceRatio);

        bestSizesOnRatioAndTolerance = getBestSizesOnRatioAndTolerance(
                sourceRatio, supportedPreviewSizes, aspectTolerance);

        // Is there no ratios within aspectTolerance
        // get best ratio without taking into account check screen width and
        // height
        if (bestSizesOnRatioAndTolerance.isEmpty()) {
            bestPreviewSize = getBestSizeOnRatio(sourceRatio,
                    supportedPreviewSizes);

            // Get tolerance-ratios and check with value nearest display width
        } else {
            bestPreviewSize = getBestSizeOnWith(width,
                    bestSizesOnRatioAndTolerance);
        }

        return bestPreviewSize;
    }

    private static List<Size> getBestSizesOnRatioAndTolerance(
            double sourceRatio, List<Size> supportedSizes, double tolerance) {
        List<Size> bestSizes = new ArrayList<Size>();

        for (Size size : supportedSizes) {

            double supportedRatio = (double) size.width / size.height;

            if (Math.abs(sourceRatio - supportedRatio) < tolerance) {
                bestSizes.add(size);
            }
        }

        return bestSizes;
    }

    private static Size getBestSizeOnRatio(double sourceRatio,
            List<Size> supportedSizes) {
        Size bestSize = null;
        double lastDiff = Double.MAX_VALUE;

        for (Size size : supportedSizes) {
            double supportedRatio = size.width / size.height;

            double diff = Math.abs(sourceRatio - supportedRatio);
            if (diff < lastDiff) {
                bestSize = size;
                lastDiff = diff;
            }
        }

        return bestSize;
    }

    private static Size getBestSizeOnWith(int width,
            List<Size> supportedSizes) {
        double lastDiff = Double.MAX_VALUE;
        Size bestSize = null;

        for (Size size : supportedSizes) {

            double diff = Math.abs(width - size.width);
            if (diff < lastDiff) {
                lastDiff = diff;
                bestSize = size;
            }
        }

        return bestSize;
    }
}

Related Tutorials