Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
//License from project: Open Source License 

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

public class Main {
    /**
     * This will return a bitmap that is loaded and appropriately scaled from
     * the filePath parameter.
     */
    public static Bitmap decodeSampledBitmapFromFile(String pathName, int width, int height) {

        // First decode with inJustDecodeBounds=true to check dimensions.
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(pathName, options);

        // If either width or height is passed in as 0, then use the actual
        // stored image dimension.
        if (width == 0) {
            width = options.outWidth;
        }
        if (height == 0) {
            height = options.outHeight;
        }

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, width, height);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(pathName, options);
    }

    /**
     * This returns the sample size that should be used when down-sampling the
     * image. This ensures that the image is scaled appropriately with respect
     * to it's final display size.
     */
    @SuppressWarnings("WeakerAccess")
    public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {

            final int halfHeight = height / 2;
            final int halfWidth = width / 2;

            // Calculate the largest inSampleSize value that is a power of 2
            // and keeps both height and width larger than the requested
            // height and width.
            while ((halfHeight / inSampleSize) > reqHeight && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }

        return inSampleSize;
    }
}