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diff --git a/src/org/cyanogenmod/wallpapers/photophase/utils/MERAlgorithm.java b/src/org/cyanogenmod/wallpapers/photophase/utils/MERAlgorithm.java
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+++ b/src/org/cyanogenmod/wallpapers/photophase/utils/MERAlgorithm.java
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+/*
+ * Copyright (C) 2013 The CyanogenMod 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 org.cyanogenmod.wallpapers.photophase.utils;
+
+import android.graphics.Rect;
+import java.util.Stack;
+
+/**
+ * The maximal empty rectangle algorithm that allows to find the rectangle with the maximal
+ * area that could be create in empty areas (in this case 0 in a byte matrix)
+ */
+//
+// Based on the source discussed at http://discuss.leetcode.com/questions/260/maximal-rectangle
+//
+public final class MERAlgorithm {
+
+    /**
+     * Method that returns the maximal empty rectangle (MER) for a matrix of bytes (1/0)
+     *
+     * @param matrix The matrix
+     * @return Rect The maximal empty rectangle
+     */
+    public static Rect getMaximalEmptyRectangle(byte[][] matrix) {
+        // Check matrix
+        int rows = matrix.length;
+        if (rows == 0) return null;
+        int cols = matrix[0].length;
+
+        // Convert to histogram
+        int[][] histogram = toHistogram(matrix);
+
+        // Find the maximal area of every histogram
+        Rect maxRect = new Rect();
+        for (int i = 0; i < rows; ++i) {
+            Rect rect = maximalRectangle(histogram[i], i);
+            if ((maxRect.width() * maxRect.height()) < (rect.width() * rect.height())) {
+                maxRect = rect;
+            }
+        }
+        return ensureBounds(maxRect, cols, rows);
+    }
+
+    /**
+     * Method that ensure the bounds of the max rectangle
+     *
+     * @param rect The rectangle to check
+     * @param cols The number of cols
+     * @param rows The number of rows
+     * @return Rect The rectangle checked
+     */
+    private static Rect ensureBounds(Rect rect, int cols, int rows) {
+        if (rect.right - rect.left >= cols) rect.right = cols;
+        if (rect.bottom - rect.top >= rows) rect.bottom = rows;
+        return rect;
+    }
+
+    /**
+     * Method that returns the maximal rectangle for an histogram of areas
+     *
+     * @return Rect The maximal rectangle histogram/area
+     */
+    @SuppressWarnings("boxing")
+    private static Rect maximalRectangle(int[] histogram, int row) {
+        Stack<Integer> stack = new Stack<Integer>();
+        int length = histogram.length;
+        Rect maxRect = new Rect();
+        int i = 0;
+        while (i < length) {
+            if (stack.isEmpty() || histogram[i] >= histogram[stack.peek()]) {
+                stack.push(i++);
+            } else {
+                Rect rect = new Rect();
+                rect.left = stack.pop();
+                rect.right = rect.left + (stack.isEmpty() ? i : (i - stack.peek() - 1));
+                rect.top = row - histogram[rect.left] + 1;
+                rect.bottom = rect.top + histogram[rect.left];
+                if ((maxRect.width() * maxRect.height()) < (rect.width() * rect.height())) {
+                    maxRect = rect;
+                }
+            }
+        }
+        while (!stack.isEmpty()) {
+            Rect rect = new Rect();
+            rect.left = stack.pop();
+            rect.right = rect.left + (stack.isEmpty() ? i : (i - stack.peek() - 1));
+            rect.top = row - histogram[rect.left] + 1;
+            rect.bottom = rect.top + histogram[rect.left];
+            if ((maxRect.width() * maxRect.height()) < (rect.width() * rect.height())) {
+                maxRect = rect;
+            }
+        }
+        return maxRect;
+    }
+
+    /**
+     * Method that converts the empty areas to a histogram
+     *
+     * @param matrix The matrix where to find the MER
+     * return int[][] The histogram of empty areas
+     */
+    private static int[][] toHistogram(byte[][] matrix) {
+        int rows = matrix.length;
+        int cols = matrix[0].length;
+        int[][] histogram = new int[rows][cols];
+        for (int h=0; h < cols; h++) {
+            if (matrix[0][h] == 0) {
+                histogram[0][h] = 1;
+            }
+        }
+        for (int w=1; w < rows; w++) {
+            for (int h=0; h < cols; h++) {
+                if (matrix[w][h] == 1) {
+                    continue;
+                }
+                histogram[w][h] = histogram[w-1][h] + 1;
+            }
+        }
+        return histogram;
+    }
+}