Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

public class Main {
    public static final int THUMBNAIL_SIZE = 256;

    public static Bitmap getThumbnail(Uri uri, Context context) throws FileNotFoundException, IOException {
        InputStream input = context.getContentResolver().openInputStream(uri);

        BitmapFactory.Options onlyBoundsOptions = new BitmapFactory.Options();
        onlyBoundsOptions.inJustDecodeBounds = true;
        onlyBoundsOptions.inDither = true;//optional
        onlyBoundsOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;//optional
        BitmapFactory.decodeStream(input, null, onlyBoundsOptions);
        input.close();
        if ((onlyBoundsOptions.outWidth == -1) || (onlyBoundsOptions.outHeight == -1))
            return null;

        int originalSize = (onlyBoundsOptions.outHeight > onlyBoundsOptions.outWidth) ? onlyBoundsOptions.outHeight
                : onlyBoundsOptions.outWidth;

        double ratio = (originalSize > THUMBNAIL_SIZE) ? (originalSize / THUMBNAIL_SIZE) : 1.0;

        BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
        bitmapOptions.inSampleSize = getPowerOfTwoForSampleRatio(ratio);
        bitmapOptions.inDither = true;//optional
        bitmapOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;//optional
        input = context.getContentResolver().openInputStream(uri);
        Bitmap bitmap = BitmapFactory.decodeStream(input, null, bitmapOptions);
        input.close();
        return bitmap;
    }

    private static int getPowerOfTwoForSampleRatio(double ratio) {
        int k = Integer.highestOneBit((int) Math.floor(ratio));
        if (k == 0)
            return 1;
        else
            return k;
    }
}