1 files changed, 313 insertions, 0 deletions
diff --git a/src/main/java/de/thedevstack/conversationsplus/utils/ImageUtil.java b/src/main/java/de/thedevstack/conversationsplus/utils/ImageUtil.java
new file mode 100644
index 00000000..3c3e1c99
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/utils/ImageUtil.java
@@ -0,0 +1,313 @@
+package de.thedevstack.conversationsplus.utils;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Canvas;
+import android.graphics.Matrix;
+import android.graphics.RectF;
+import android.media.ExifInterface;
+import android.net.Uri;
+import android.util.Log;
+import android.util.LruCache;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+
+import de.thedevstack.conversationsplus.entities.Message;
+import de.thedevstack.conversationsplus.persistance.FileBackend;
+
+/**
+ * This util provides
+ */
+public final class ImageUtil {
+    private static LruCache<String, Bitmap> BITMAP_CACHE;
+
+    /**
+     * Returns a bitmap from the cache.
+     * @see LruCache#get(Object) for details
+     * @param key the key of the bitmap to get
+     * @return the bitmap
+     */
+    public static Bitmap getBitmapFromCache(String key) {
+        return BITMAP_CACHE.get(key);
+    }
+
+    /**
+     * Adds a bitmap with the given key to the cache.
+     * @see LruCache#put(Object, Object) for details
+     * @param key the key to identify this bitmap
+     * @param bitmap the bitmap to cache
+     */
+    public static void addBitmapToCache(String key, Bitmap bitmap) {
+        BITMAP_CACHE.put(key, bitmap);
+    }
+
+    /**
+     * Removes the bitmap with given key from the cache.
+     * @param key the key of the bitmap to remove
+     */
+    public static void removeBitmapFromCache(String key) {
+        BITMAP_CACHE.remove(key);
+    }
+
+    /**
+     * Clears the cache.
+     * @see LruCache#evictAll() for more details.
+     */
+    public static void evictBitmapCache() {
+        BITMAP_CACHE.evictAll();
+    }
+
+    /**
+     * Initializes the bitmap cache.
+     * This has to be executed once on application start.
+     * @see LruCache#LruCache(int) for details
+     */
+    public static void initBitmapCache() {
+        Log.i("Conversations+ImageUtil", "Initializing BitmapCache");
+        final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
+        final int cacheSize = maxMemory / 8;
+        BITMAP_CACHE = new LruCache<String, Bitmap>(cacheSize) {
+            @Override
+            protected int sizeOf(final String key, final Bitmap bitmap) {
+                return bitmap.getByteCount() / 1024;
+            }
+        };
+    }
+
+    /**
+     * Resizes a given bitmap and return a new and resized bitmap.
+     * The bitmap is only resized if either the width or the height of the original bitmap is smaller than the given size.
+     * @param originalBitmap the bitmap to resize
+     * @param size the size to scale to
+     * @return new and resized bitmap or the original bitmap if width and height are smaller than size
+     */
+    public static Bitmap resize(Bitmap originalBitmap, int size) {
+        int w = originalBitmap.getWidth();
+        int h = originalBitmap.getHeight();
+        if (Math.max(w, h) > size) {
+            int scalledW;
+            int scalledH;
+            if (w <= h) {
+                scalledW = (int) (w / ((double) h / size));
+                scalledH = size;
+            } else {
+                scalledW = size;
+                scalledH = (int) (h / ((double) w / size));
+            }
+            return Bitmap.createScaledBitmap(originalBitmap, scalledW, scalledH, true);
+        } else {
+            return originalBitmap;
+        }
+    }
+
+    /**
+     * Returns the rotation from the exif information of an image identified with the given uri.
+     * The orientation is retrieved by parsing the stream of the image.
+     * FileNotFoundException is silently ignored.
+     * @param image the uri of the image to get the rotation
+     * @return the rotation value for the image, <code>0</code> if the file cannot be found.
+     */
+    public static int getRotation(Uri image) {
+        InputStream is = null;
+        try {
+            is = StreamUtil.openInputStreamFromContentResolver(image);
+            return ExifHelper.getOrientation(is);
+        } catch (FileNotFoundException e) {
+            return 0;
+        } finally {
+            StreamUtil.close(is);
+        }
+    }
+
+    /**
+     * Returns a thumbnail for a bitmap in a message.
+     * @param message the message to get the thumbnail for
+     * @param size the size to resize the original image to
+     * @param cacheOnly whether only cached images should be returned or not
+     * @return the resized thumbail
+     * @throws FileNotFoundException if the original image does not exist anymore or an IOException occurs.
+     */
+    public static Bitmap getThumbnail(Message message, int size, boolean cacheOnly)
+            throws FileNotFoundException {
+        Bitmap thumbnail = ImageUtil.getBitmapFromCache(message.getUuid());
+        if ((thumbnail == null) && (!cacheOnly)) {
+            File file = FileBackend.getFile(message);
+            BitmapFactory.Options options = new BitmapFactory.Options();
+            options.inSampleSize = calcSampleSize(file, size);
+            Bitmap fullsize = BitmapFactory.decodeFile(file.getAbsolutePath(),options);
+            if (fullsize == null) {
+                throw new FileNotFoundException();
+            }
+            thumbnail = resize(fullsize, size);
+            thumbnail = rotate(thumbnail, file.getAbsolutePath());
+
+            ImageUtil.addBitmapToCache(message.getUuid(), thumbnail);
+        }
+        return thumbnail;
+    }
+
+    /**
+     * Rotates an bitmap. Only the values 90°, 180° and 270° are considered to rotate the image.
+     * The orientation information is read using the ExifInterface.
+     * @param original the original bitmap
+     * @param srcPath the path to the original bitmap (used to read the exif information)
+     * @return rotated bitmap, or original bitmap if criteria are not met
+     * @throws IOException
+     */
+    public static Bitmap rotate(Bitmap original, String srcPath) {
+        try {
+            ExifInterface exif = new ExifInterface(srcPath);
+            int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_UNDEFINED);
+            int rotation = 0;
+            switch (orientation) {
+                case ExifInterface.ORIENTATION_ROTATE_90:
+                    rotation = 90;
+                    break;
+                case ExifInterface.ORIENTATION_ROTATE_180:
+                    rotation = 180;
+                    break;
+                case ExifInterface.ORIENTATION_ROTATE_270:
+                    rotation = 270;
+                    break;
+            }
+            if (rotation > 0) {
+                return rotate(original, rotation);
+            }
+        } catch (IOException e) {
+            Log.w("filebackend", "Error while rotating image, returning original (" + e.getMessage() + ")");
+        }
+        return original;
+    }
+
+    /**
+     * Rotates a bitmap with given degrees.
+     * @param bitmap the bitmap to be rotated
+     * @param degree the degrees to rotate the bitmap
+     * @return a newly created bitmap
+     */
+    public static Bitmap rotate(Bitmap bitmap, int degree) {
+        int w = bitmap.getWidth();
+        int h = bitmap.getHeight();
+        Matrix mtx = new Matrix();
+        mtx.postRotate(degree);
+        return Bitmap.createBitmap(bitmap, 0, 0, w, h, mtx, true);
+    }
+
+
+    public static Bitmap cropCenterSquare(Uri image, int size) {
+        if (image == null) {
+            return null;
+        }
+        InputStream is = null;
+        try {
+            BitmapFactory.Options options = new BitmapFactory.Options();
+            options.inSampleSize = calcSampleSize(image, size);
+            is = StreamUtil.openInputStreamFromContentResolver(image);
+            Bitmap input = BitmapFactory.decodeStream(is, null, options);
+            if (input == null) {
+                return null;
+            } else {
+                int rotation = getRotation(image);
+                if (rotation > 0) {
+                    input = rotate(input, rotation);
+                }
+                return cropCenterSquare(input, size);
+            }
+        } catch (FileNotFoundException e) {
+            return null;
+        } finally {
+            StreamUtil.close(is);
+        }
+    }
+
+    public static Bitmap cropCenter(Uri image, int newHeight, int newWidth) {
+        if (image == null) {
+            return null;
+        }
+        InputStream is = null;
+        try {
+            BitmapFactory.Options options = new BitmapFactory.Options();
+            options.inSampleSize = calcSampleSize(image,Math.max(newHeight, newWidth));
+            is = StreamUtil.openInputStreamFromContentResolver(image);
+            Bitmap source = BitmapFactory.decodeStream(is, null, options);
+            if (source == null) {
+                return null;
+            }
+            int sourceWidth = source.getWidth();
+            int sourceHeight = source.getHeight();
+            float xScale = (float) newWidth / sourceWidth;
+            float yScale = (float) newHeight / sourceHeight;
+            float scale = Math.max(xScale, yScale);
+            float scaledWidth = scale * sourceWidth;
+            float scaledHeight = scale * sourceHeight;
+            float left = (newWidth - scaledWidth) / 2;
+            float top = (newHeight - scaledHeight) / 2;
+
+            RectF targetRect = new RectF(left, top, left + scaledWidth, top + scaledHeight);
+            Bitmap dest = Bitmap.createBitmap(newWidth, newHeight, Bitmap.Config.ARGB_8888);
+            Canvas canvas = new Canvas(dest);
+            canvas.drawBitmap(source, null, targetRect, null);
+            return dest;
+        } catch (FileNotFoundException e) {
+            return null;
+        } finally {
+            StreamUtil.close(is);
+        }
+    }
+
+    public static Bitmap cropCenterSquare(Bitmap input, int size) {
+        int w = input.getWidth();
+        int h = input.getHeight();
+
+        float scale = Math.max((float) size / h, (float) size / w);
+
+        float outWidth = scale * w;
+        float outHeight = scale * h;
+        float left = (size - outWidth) / 2;
+        float top = (size - outHeight) / 2;
+        RectF target = new RectF(left, top, left + outWidth, top + outHeight);
+
+        Bitmap output = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
+        Canvas canvas = new Canvas(output);
+        canvas.drawBitmap(input, null, target, null);
+        return output;
+    }
+
+    public static int calcSampleSize(Uri image, int size) throws FileNotFoundException {
+        BitmapFactory.Options options = new BitmapFactory.Options();
+        options.inJustDecodeBounds = true;
+        BitmapFactory.decodeStream(StreamUtil.openInputStreamFromContentResolver(image), null, options);
+        return calcSampleSize(options, size);
+    }
+
+    public static int calcSampleSize(File image, int size) {
+        BitmapFactory.Options options = new BitmapFactory.Options();
+        options.inJustDecodeBounds = true;
+        BitmapFactory.decodeFile(image.getAbsolutePath(), options);
+        return calcSampleSize(options, size);
+    }
+
+    public static int calcSampleSize(BitmapFactory.Options options, int size) {
+        int height = options.outHeight;
+        int width = options.outWidth;
+        int inSampleSize = 1;
+
+        if (height > size || width > size) {
+            int halfHeight = height / 2;
+            int halfWidth = width / 2;
+
+            while ((halfHeight / inSampleSize) > size
+                    && (halfWidth / inSampleSize) > size) {
+                inSampleSize *= 2;
+            }
+        }
+        return inSampleSize;
+    }
+
+    private ImageUtil() {
+        // Static helper class
+    }
+}