Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
//License from project: Apache License 

import android.content.ContentResolver;

import android.content.res.AssetFileDescriptor;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import android.net.Uri;

import android.util.DisplayMetrics;
import android.util.TypedValue;
import java.io.File;
import java.io.IOException;

public class Main {
    public static Bitmap decodeSampledBitmapFromFile(Resources res, ContentResolver contentResolver, File file,
            float reqWidthInDip, float reqHeightInDip) throws IOException {

        Bitmap bitmap;
        AssetFileDescriptor fileDescriptor;
        int reqWidthInPixel = (int) dipToPixels(res, reqWidthInDip);
        int reqHeightInPixel = (int) dipToPixels(res, reqHeightInDip);
        fileDescriptor = contentResolver.openAssetFileDescriptor(Uri.fromFile(file), "r");

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidthInPixel, reqHeightInPixel);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bitmap = BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);
        fileDescriptor.close();
        return bitmap;
    }

    public static Bitmap decodeSampledBitmapFromFile(Resources res, ContentResolver contentResolver, File file,
            int reqWidthInPixel, int reqHeightInPixel) throws IOException {

        Bitmap bitmap;
        AssetFileDescriptor fileDescriptor;

        fileDescriptor = contentResolver.openAssetFileDescriptor(Uri.fromFile(file), "r");

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidthInPixel, reqHeightInPixel);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bitmap = BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);
        fileDescriptor.close();
        return bitmap;
    }

    public static Bitmap decodeSampledBitmapFromFile(Resources res, ContentResolver contentResolver, Uri uri,
            float reqWidthInDip, float reqHeightInDip) throws IOException {

        Bitmap bitmap;
        AssetFileDescriptor fileDescriptor;
        int reqWidthInPixel = (int) dipToPixels(res, reqWidthInDip);
        int reqHeightInPixel = (int) dipToPixels(res, reqHeightInDip);
        fileDescriptor = contentResolver.openAssetFileDescriptor(uri, "r");

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidthInPixel, reqHeightInPixel);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bitmap = BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);
        fileDescriptor.close();
        return bitmap;
    }

    public static Bitmap decodeSampledBitmapFromFile(Resources res, ContentResolver contentResolver, Uri uri,
            int reqWidthInPixel, int reqHeightInPixel) throws IOException {

        Bitmap bitmap;
        AssetFileDescriptor fileDescriptor;

        fileDescriptor = contentResolver.openAssetFileDescriptor(uri, "r");

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidthInPixel, reqHeightInPixel);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bitmap = BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);
        fileDescriptor.close();
        return bitmap;
    }

    public static float dipToPixels(Resources res, float dipValue) {
        DisplayMetrics metrics = res.getDisplayMetrics();
        return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dipValue, metrics);
    }

    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;
    }
}