1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.example.android.mediabrowserservice.utils; 17 18 import android.graphics.Bitmap; 19 import android.graphics.BitmapFactory; 20 21 import java.io.BufferedInputStream; 22 import java.io.IOException; 23 import java.io.InputStream; 24 import java.net.HttpURLConnection; 25 import java.net.URL; 26 27 public class BitmapHelper { 28 private static final String TAG = LogHelper.makeLogTag(BitmapHelper.class); 29 30 // Max read limit that we allow our input stream to mark/reset. 31 private static final int MAX_READ_LIMIT_PER_IMG = 1024 * 1024; 32 33 public static Bitmap scaleBitmap(Bitmap src, int maxWidth, int maxHeight) { 34 double scaleFactor = Math.min( 35 ((double) maxWidth)/src.getWidth(), ((double) maxHeight)/src.getHeight()); 36 return Bitmap.createScaledBitmap(src, 37 (int) (src.getWidth() * scaleFactor), (int) (src.getHeight() * scaleFactor), false); 38 } 39 40 public static Bitmap scaleBitmap(int scaleFactor, InputStream is) { 41 // Get the dimensions of the bitmap 42 BitmapFactory.Options bmOptions = new BitmapFactory.Options(); 43 44 // Decode the image file into a Bitmap sized to fill the View 45 bmOptions.inJustDecodeBounds = false; 46 bmOptions.inSampleSize = scaleFactor; 47 48 return BitmapFactory.decodeStream(is, null, bmOptions); 49 } 50 51 public static int findScaleFactor(int targetW, int targetH, InputStream is) { 52 // Get the dimensions of the bitmap 53 BitmapFactory.Options bmOptions = new BitmapFactory.Options(); 54 bmOptions.inJustDecodeBounds = true; 55 BitmapFactory.decodeStream(is, null, bmOptions); 56 int actualW = bmOptions.outWidth; 57 int actualH = bmOptions.outHeight; 58 59 // Determine how much to scale down the image 60 return Math.min(actualW/targetW, actualH/targetH); 61 } 62 63 @SuppressWarnings("SameParameterValue") 64 public static Bitmap fetchAndRescaleBitmap(String uri, int width, int height) 65 throws IOException { 66 URL url = new URL(uri); 67 BufferedInputStream is = null; 68 try { 69 HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection(); 70 is = new BufferedInputStream(urlConnection.getInputStream()); 71 is.mark(MAX_READ_LIMIT_PER_IMG); 72 int scaleFactor = findScaleFactor(width, height, is); 73 LogHelper.d(TAG, "Scaling bitmap ", uri, " by factor ", scaleFactor, " to support ", 74 width, "x", height, "requested dimension"); 75 is.reset(); 76 return scaleBitmap(scaleFactor, is); 77 } finally { 78 if (is != null) { 79 is.close(); 80 } 81 } 82 } 83 } 84
