Java tutorial
/* * Copyright (C) 2008 Esmertec AG. * Copyright (C) 2008 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package mobisocial.musubi.util; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import org.apache.commons.io.IOUtils; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import android.content.Context; import android.database.Cursor; import android.graphics.Bitmap; import android.graphics.Bitmap.CompressFormat; import android.graphics.BitmapFactory; import android.graphics.Matrix; import android.net.Uri; import android.provider.MediaStore.Images; import android.text.TextUtils; import android.util.Config; import android.util.Log; import android.webkit.MimeTypeMap; public class UriImage { /** * The quality parameter which is used to compress JPEG images. */ public static final int IMAGE_COMPRESSION_QUALITY = 80; /** * The minimum quality parameter which is used to compress JPEG images. */ public static final int MINIMUM_IMAGE_COMPRESSION_QUALITY = 50; private static final String TAG = "Mms/image"; private static final boolean DEBUG = true; private static final boolean LOCAL_LOGV = DEBUG ? Config.LOGD : Config.LOGV; private final Context mContext; private final Uri mUri; private String mContentType; private String mPath; private String mSrc; private int mWidth; private int mHeight; private float mRotation; private byte[] mByteCache; private boolean mDecodedBounds = false; public UriImage(Context context, Uri uri) { if ((null == context) || (null == uri)) { throw new IllegalArgumentException(); } mRotation = PhotoTaker.rotationForImage(context, uri); String scheme = uri.getScheme(); if (scheme.equals("content")) { try { initFromContentUri(context, uri); } catch (Exception e) { Log.w(TAG, "last-ditch image params"); mPath = uri.getPath(); mContentType = context.getContentResolver().getType(uri); } } else if (uri.getScheme().equals("file")) { initFromFile(context, uri); } else { mPath = uri.getPath(); } mSrc = mPath.substring(mPath.lastIndexOf('/') + 1); if (mSrc.startsWith(".") && mSrc.length() > 1) { mSrc = mSrc.substring(1); } // Some MMSCs appear to have problems with filenames // containing a space. So just replace them with // underscores in the name, which is typically not // visible to the user anyway. mSrc = mSrc.replace(' ', '_'); mContext = context; mUri = uri; } private void initFromFile(Context context, Uri uri) { mPath = uri.getPath(); MimeTypeMap mimeTypeMap = MimeTypeMap.getSingleton(); String extension = MimeTypeMap.getFileExtensionFromUrl(mPath); if (TextUtils.isEmpty(extension)) { // getMimeTypeFromExtension() doesn't handle spaces in filenames nor can it handle // urlEncoded strings. Let's try one last time at finding the extension. int dotPos = mPath.lastIndexOf('.'); if (0 <= dotPos) { extension = mPath.substring(dotPos + 1); } } mContentType = mimeTypeMap.getMimeTypeFromExtension(extension); // It's ok if mContentType is null. Eventually we'll show a toast telling the // user the picture couldn't be attached. } private void initFromContentUri(Context context, Uri uri) { Cursor c = context.getContentResolver().query(uri, null, null, null, null); if (c == null) { throw new IllegalArgumentException("Query on " + uri + " returns null result."); } try { if ((c.getCount() != 1) || !c.moveToFirst()) { throw new IllegalArgumentException("Query on " + uri + " returns 0 or multiple rows."); } String filePath = c.getString(c.getColumnIndexOrThrow(Images.Media.DATA)); mContentType = c.getString(c.getColumnIndexOrThrow(Images.Media.MIME_TYPE)); mPath = filePath; } finally { c.close(); } } private void decodeBoundsInfo() throws IOException { InputStream input = null; try { input = openInputStream(mUri); BitmapFactory.Options opt = new BitmapFactory.Options(); opt.inJustDecodeBounds = true; BitmapFactory.decodeStream(input, null, opt); mWidth = opt.outWidth; mHeight = opt.outHeight; } catch (FileNotFoundException e) { // Ignore Log.e(TAG, "IOException caught while opening stream", e); } finally { if (null != input) { try { input.close(); } catch (IOException e) { // Ignore Log.e(TAG, "IOException caught while closing stream", e); } } } } public String getContentType() { return mContentType; } public String getSrc() { return mSrc; } public int getWidth() { return mWidth; } public int getHeight() { return mHeight; } private static final int NUMBER_OF_RESIZE_ATTEMPTS = 4; public byte[] getResizedImageData(int widthLimit, int heightLimit, int byteLimit) throws IOException { return getResizedImageData(widthLimit, heightLimit, byteLimit, false); } /** * Returns the bytes for this UriImage. If the uri for the image is remote, * then this code must not be run on the main thread. */ public byte[] getResizedImageData(int widthLimit, int heightLimit, int byteLimit, boolean square) throws IOException { if (!mDecodedBounds) { decodeBoundsInfo(); mDecodedBounds = true; } InputStream input = null; try { int inDensity = 0; int targetDensity = 0; BitmapFactory.Options read_options = new BitmapFactory.Options(); read_options.inJustDecodeBounds = true; input = openInputStream(mUri); BitmapFactory.decodeStream(input, null, read_options); if (read_options.outWidth > widthLimit || read_options.outHeight > heightLimit) { //we need to scale if (read_options.outWidth / widthLimit > read_options.outHeight / heightLimit) { //width is the large edge if (read_options.outWidth * heightLimit > widthLimit * read_options.outHeight) { //incoming image is wider than target inDensity = read_options.outWidth; targetDensity = widthLimit; } else { //incoming image is taller than target inDensity = read_options.outHeight; targetDensity = heightLimit; } } else { //height is the long edge, swap the limits if (read_options.outWidth * widthLimit > heightLimit * read_options.outHeight) { //incoming image is wider than target inDensity = read_options.outWidth; targetDensity = heightLimit; } else { //incoming image is taller than target inDensity = read_options.outHeight; targetDensity = widthLimit; } } } else { //no scale if (read_options.outWidth > read_options.outHeight) { inDensity = targetDensity = read_options.outWidth; } else { inDensity = targetDensity = read_options.outHeight; } } if (Log.isLoggable(TAG, Log.VERBOSE)) { Log.v(TAG, "getResizedImageData: wlimit=" + widthLimit + ", hlimit=" + heightLimit + ", sizeLimit=" + byteLimit + ", mWidth=" + mWidth + ", mHeight=" + mHeight + ", initialRatio=" + targetDensity + "/" + inDensity); } ByteArrayOutputStream os = null; int attempts = 1; int lowMemoryReduce = 1; do { BitmapFactory.Options options = new BitmapFactory.Options(); options.inDensity = inDensity; options.inSampleSize = lowMemoryReduce; options.inScaled = lowMemoryReduce == 1; options.inTargetDensity = targetDensity; //no purgeable because we are only trying to resave this if (input != null) input.close(); input = openInputStream(mUri); int quality = IMAGE_COMPRESSION_QUALITY; try { Bitmap b = BitmapFactory.decodeStream(input, null, options); if (b == null) { return null; } if (options.outWidth > widthLimit + 1 || options.outHeight > heightLimit + 1) { // The decoder does not support the inSampleSize option. // Scale the bitmap using Bitmap library. int scaledWidth; int scaledHeight; scaledWidth = options.outWidth * targetDensity / inDensity; scaledHeight = options.outHeight * targetDensity / inDensity; if (Log.isLoggable(TAG, Log.VERBOSE)) { Log.v(TAG, "getResizedImageData: retry scaling using " + "Bitmap.createScaledBitmap: w=" + scaledWidth + ", h=" + scaledHeight); } if (square) { int w = b.getWidth(); int h = b.getHeight(); int dim = Math.min(w, h); b = Bitmap.createBitmap(b, (w - dim) / 2, (h - dim) / 2, dim, dim); scaledWidth = dim; scaledHeight = dim; } Bitmap b2 = Bitmap.createScaledBitmap(b, scaledWidth, scaledHeight, false); b.recycle(); b = b2; if (b == null) { return null; } } Matrix matrix = new Matrix(); if (mRotation != 0f) { matrix.preRotate(mRotation); } Bitmap old = b; b = Bitmap.createBitmap(old, 0, 0, old.getWidth(), old.getHeight(), matrix, true); // Compress the image into a JPG. Start with MessageUtils.IMAGE_COMPRESSION_QUALITY. // In case that the image byte size is still too large reduce the quality in // proportion to the desired byte size. Should the quality fall below // MINIMUM_IMAGE_COMPRESSION_QUALITY skip a compression attempt and we will enter // the next round with a smaller image to start with. os = new ByteArrayOutputStream(); b.compress(CompressFormat.JPEG, quality, os); int jpgFileSize = os.size(); if (jpgFileSize > byteLimit) { int reducedQuality = quality * byteLimit / jpgFileSize; //always try to squish it before computing the new size if (reducedQuality < MINIMUM_IMAGE_COMPRESSION_QUALITY) { reducedQuality = MINIMUM_IMAGE_COMPRESSION_QUALITY; } quality = reducedQuality; if (Log.isLoggable(TAG, Log.VERBOSE)) { Log.v(TAG, "getResizedImageData: compress(2) w/ quality=" + quality); } os = new ByteArrayOutputStream(); b.compress(CompressFormat.JPEG, quality, os); } b.recycle(); // done with the bitmap, release the memory } catch (java.lang.OutOfMemoryError e) { Log.w(TAG, "getResizedImageData - image too big (OutOfMemoryError), will try " + " with smaller scale factor, cur scale factor", e); lowMemoryReduce *= 2; // fall through and keep trying with a smaller scale factor. } if (true || Log.isLoggable(TAG, Log.VERBOSE)) { Log.v(TAG, "attempt=" + attempts + " size=" + (os == null ? 0 : os.size()) + " width=" + options.outWidth + " height=" + options.outHeight + " Ratio=" + targetDensity + "/" + inDensity + " quality=" + quality); } //move halfway to the target targetDensity = (os == null) ? (int) (targetDensity * .8) : (targetDensity * byteLimit / os.size() + targetDensity) / 2; attempts++; } while ((os == null || os.size() > byteLimit) && attempts < NUMBER_OF_RESIZE_ATTEMPTS); return os == null ? null : os.toByteArray(); } catch (Throwable t) { Log.e(TAG, t.getMessage(), t); return null; } finally { if (input != null) { try { input.close(); } catch (IOException e) { Log.e(TAG, e.getMessage(), e); } } } } private InputStream openInputStream(Uri uri) throws IOException { String scheme = uri.getScheme(); if ("content".equals(scheme)) { return mContext.getContentResolver().openInputStream(mUri); } else if (scheme.startsWith("http")) { if (mByteCache == null) { DefaultHttpClient c = new DefaultHttpClient(); HttpGet get = new HttpGet(uri.toString()); HttpResponse response = c.execute(get); mByteCache = IOUtils.toByteArray(response.getEntity().getContent()); } return new ByteArrayInputStream(mByteCache); } else if (scheme.equals("file")) { return new FileInputStream(uri.getPath()); } else { throw new IOException("Unmatched uri scheme " + scheme); } } }