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      1 /*
      2  * Copyright (C) 2013 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 
     17 package com.android.photos;
     18 
     19 import android.annotation.TargetApi;
     20 import android.content.Context;
     21 import android.graphics.Bitmap;
     22 import android.graphics.Bitmap.Config;
     23 import android.graphics.BitmapFactory;
     24 import android.graphics.BitmapRegionDecoder;
     25 import android.graphics.Canvas;
     26 import android.graphics.Rect;
     27 import android.os.Build;
     28 import android.os.Build.VERSION_CODES;
     29 import android.util.Log;
     30 
     31 import com.android.gallery3d.common.BitmapUtils;
     32 import com.android.gallery3d.glrenderer.BasicTexture;
     33 import com.android.gallery3d.glrenderer.BitmapTexture;
     34 import com.android.photos.views.TiledImageRenderer;
     35 
     36 import java.io.IOException;
     37 
     38 /**
     39  * A {@link com.android.photos.views.TiledImageRenderer.TileSource} using
     40  * {@link BitmapRegionDecoder} to wrap a local file
     41  */
     42 @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1)
     43 public class BitmapRegionTileSource implements TiledImageRenderer.TileSource {
     44 
     45     private static final String TAG = "BitmapRegionTileSource";
     46 
     47     private static final boolean REUSE_BITMAP =
     48             Build.VERSION.SDK_INT >= VERSION_CODES.JELLY_BEAN;
     49     private static final int GL_SIZE_LIMIT = 2048;
     50     // This must be no larger than half the size of the GL_SIZE_LIMIT
     51     // due to decodePreview being allowed to be up to 2x the size of the target
     52     private static final int MAX_PREVIEW_SIZE = 1024;
     53 
     54     BitmapRegionDecoder mDecoder;
     55     int mWidth;
     56     int mHeight;
     57     int mTileSize;
     58     private BasicTexture mPreview;
     59     private final int mRotation;
     60 
     61     // For use only by getTile
     62     private Rect mWantRegion = new Rect();
     63     private Rect mOverlapRegion = new Rect();
     64     private BitmapFactory.Options mOptions;
     65     private Canvas mCanvas;
     66 
     67     public BitmapRegionTileSource(Context context, String path, int previewSize, int rotation) {
     68         mTileSize = TiledImageRenderer.suggestedTileSize(context);
     69         mRotation = rotation;
     70         try {
     71             mDecoder = BitmapRegionDecoder.newInstance(path, true);
     72             mWidth = mDecoder.getWidth();
     73             mHeight = mDecoder.getHeight();
     74         } catch (IOException e) {
     75             Log.w("BitmapRegionTileSource", "ctor failed", e);
     76         }
     77         mOptions = new BitmapFactory.Options();
     78         mOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;
     79         mOptions.inPreferQualityOverSpeed = true;
     80         mOptions.inTempStorage = new byte[16 * 1024];
     81         if (previewSize != 0) {
     82             previewSize = Math.min(previewSize, MAX_PREVIEW_SIZE);
     83             // Although this is the same size as the Bitmap that is likely already
     84             // loaded, the lifecycle is different and interactions are on a different
     85             // thread. Thus to simplify, this source will decode its own bitmap.
     86             Bitmap preview = decodePreview(path, previewSize);
     87             if (preview.getWidth() <= GL_SIZE_LIMIT && preview.getHeight() <= GL_SIZE_LIMIT) {
     88                 mPreview = new BitmapTexture(preview);
     89             } else {
     90                 Log.w(TAG, String.format(
     91                         "Failed to create preview of apropriate size! "
     92                         + " in: %dx%d, out: %dx%d",
     93                         mWidth, mHeight,
     94                         preview.getWidth(), preview.getHeight()));
     95             }
     96         }
     97     }
     98 
     99     @Override
    100     public int getTileSize() {
    101         return mTileSize;
    102     }
    103 
    104     @Override
    105     public int getImageWidth() {
    106         return mWidth;
    107     }
    108 
    109     @Override
    110     public int getImageHeight() {
    111         return mHeight;
    112     }
    113 
    114     @Override
    115     public BasicTexture getPreview() {
    116         return mPreview;
    117     }
    118 
    119     @Override
    120     public int getRotation() {
    121         return mRotation;
    122     }
    123 
    124     @Override
    125     public Bitmap getTile(int level, int x, int y, Bitmap bitmap) {
    126         int tileSize = getTileSize();
    127         if (!REUSE_BITMAP) {
    128             return getTileWithoutReusingBitmap(level, x, y, tileSize);
    129         }
    130 
    131         int t = tileSize << level;
    132         mWantRegion.set(x, y, x + t, y + t);
    133 
    134         if (bitmap == null) {
    135             bitmap = Bitmap.createBitmap(tileSize, tileSize, Bitmap.Config.ARGB_8888);
    136         }
    137 
    138         mOptions.inSampleSize = (1 << level);
    139         mOptions.inBitmap = bitmap;
    140 
    141         try {
    142             bitmap = mDecoder.decodeRegion(mWantRegion, mOptions);
    143         } finally {
    144             if (mOptions.inBitmap != bitmap && mOptions.inBitmap != null) {
    145                 mOptions.inBitmap = null;
    146             }
    147         }
    148 
    149         if (bitmap == null) {
    150             Log.w("BitmapRegionTileSource", "fail in decoding region");
    151         }
    152         return bitmap;
    153     }
    154 
    155     private Bitmap getTileWithoutReusingBitmap(
    156             int level, int x, int y, int tileSize) {
    157 
    158         int t = tileSize << level;
    159         mWantRegion.set(x, y, x + t, y + t);
    160 
    161         mOverlapRegion.set(0, 0, mWidth, mHeight);
    162 
    163         mOptions.inSampleSize = (1 << level);
    164         Bitmap bitmap = mDecoder.decodeRegion(mOverlapRegion, mOptions);
    165 
    166         if (bitmap == null) {
    167             Log.w(TAG, "fail in decoding region");
    168         }
    169 
    170         if (mWantRegion.equals(mOverlapRegion)) {
    171             return bitmap;
    172         }
    173 
    174         Bitmap result = Bitmap.createBitmap(tileSize, tileSize, Config.ARGB_8888);
    175         if (mCanvas == null) {
    176             mCanvas = new Canvas();
    177         }
    178         mCanvas.setBitmap(result);
    179         mCanvas.drawBitmap(bitmap,
    180                 (mOverlapRegion.left - mWantRegion.left) >> level,
    181                 (mOverlapRegion.top - mWantRegion.top) >> level, null);
    182         mCanvas.setBitmap(null);
    183         return result;
    184     }
    185 
    186     /**
    187      * Note that the returned bitmap may have a long edge that's longer
    188      * than the targetSize, but it will always be less than 2x the targetSize
    189      */
    190     private Bitmap decodePreview(String file, int targetSize) {
    191         float scale = (float) targetSize / Math.max(mWidth, mHeight);
    192         mOptions.inSampleSize = BitmapUtils.computeSampleSizeLarger(scale);
    193         mOptions.inJustDecodeBounds = false;
    194 
    195         Bitmap result = BitmapFactory.decodeFile(file, mOptions);
    196         if (result == null) {
    197             return null;
    198         }
    199 
    200         // We need to resize down if the decoder does not support inSampleSize
    201         // or didn't support the specified inSampleSize (some decoders only do powers of 2)
    202         scale = (float) targetSize / (float) (Math.max(result.getWidth(), result.getHeight()));
    203 
    204         if (scale <= 0.5) {
    205             result = BitmapUtils.resizeBitmapByScale(result, scale, true);
    206         }
    207         return ensureGLCompatibleBitmap(result);
    208     }
    209 
    210     private static Bitmap ensureGLCompatibleBitmap(Bitmap bitmap) {
    211         if (bitmap == null || bitmap.getConfig() != null) {
    212             return bitmap;
    213         }
    214         Bitmap newBitmap = bitmap.copy(Config.ARGB_8888, false);
    215         bitmap.recycle();
    216         return newBitmap;
    217     }
    218 }
    219