MagicCrop is now fully working

AbyxBelgium · Jun 7, 2017 · b3ce109 · b3ce109
1 parent 87200e9
commit b3ce109
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Showing 4 changed files with 62 additions and 74 deletions.
diff --git a/app/src/androidTest/java/be/abyx/aurora/ExampleInstrumentedTest.java b/app/src/androidTest/java/be/abyx/aurora/ExampleInstrumentedTest.java
@@ -64,7 +64,7 @@ public void testSimpleGradientAurora() throws Exception {
 
         Bitmap gradient = factory.createAuroraBasedUponColour(output, 400, 800);
 
-        saveImageToExternalStorage(gradient);
+        saveImageToExternalStorage(gradient, Bitmap.CompressFormat.JPEG);
     }
 
     @Test
@@ -78,23 +78,39 @@ public void testBlurryAurora() throws Exception {
 
         Bitmap gradient = factory.createAuroraBasedUponDrawable(redImage, new BlurryAurora(appContext), 1200, 1920);
 
-        saveImageToExternalStorage(gradient);
+        saveImageToExternalStorage(gradient, Bitmap.CompressFormat.JPEG);
     }
 
-    private void saveImageToExternalStorage(Bitmap finalBitmap) {
+    @Test
+    public void testMagicCrop() throws Exception {
+        Context appContext = InstrumentationRegistry.getTargetContext();
+
+        Drawable logo = getInstrumentation().getContext().getResources().getDrawable(be.abyx.aurora.test.R.drawable.delhaize, null);
+        ImageUtils utils = new ImageUtils(appContext);
+
+        Bitmap cropped = utils.magicCrop(((BitmapDrawable) logo).getBitmap(), Color.WHITE, 0.75f);
+        saveImageToExternalStorage(cropped, Bitmap.CompressFormat.PNG);
+    }
+
+    private void saveImageToExternalStorage(Bitmap finalBitmap, Bitmap.CompressFormat format) {
         File myDir = getInstrumentation().getContext().getExternalFilesDir("gradient");
         myDir.mkdirs();
         Random generator = new Random();
         int n = 10000;
         n = generator.nextInt(n);
-        String fname = "Image-" + n + ".jpg";
+        String fname;
+        if (format.equals(Bitmap.CompressFormat.JPEG)) {
+            fname = "Image-" + n + ".jpg";
+        } else {
+            fname = "Image-" + n + ".png";
+        }
         File file = new File(myDir, fname);
         System.out.println(file.getAbsolutePath());
         if (file.exists())
             file.delete();
         try {
             FileOutputStream out = new FileOutputStream(file);
-            finalBitmap.compress(Bitmap.CompressFormat.JPEG, 98, out);
+            finalBitmap.compress(format, 100, out);
             out.flush();
             out.close();
         }

diff --git a/app/src/androidTest/res/drawable/delhaize.png b/app/src/androidTest/res/drawable/delhaize.png
diff --git a/app/src/main/java/be/abyx/aurora/ColourParser.java b/app/src/main/java/be/abyx/aurora/ColourParser.java
diff --git a/app/src/main/java/be/abyx/aurora/ImageUtils.java b/app/src/main/java/be/abyx/aurora/ImageUtils.java
@@ -26,43 +26,65 @@ public ImageUtils(Context context) {
      *
      * @param input A Bitmap that should be automatically cropped.
      * @param colour The colour of the edges that should be removed.
+     * @param tolerance How much a colour can deviate from the real given value and should still
+     *                  be removed (A value between 0 and 1 where 1 indicates full tolerance).
+     * @return Bitmap A new Bitmap whose corners are removed.
      */
-    public void magicCrop(Bitmap input, int colour) {
-        BitmapFactory.Options opts = new BitmapFactory.Options();
-        opts.inScaled = false;
-
-        Bitmap originalBitmap = BitmapFactory.decodeResource(context.getResources(), R.raw.aurora_fancy_template, opts);
-
-        int width = originalBitmap.getWidth();
-        int height = originalBitmap.getHeight();
+    public Bitmap magicCrop(Bitmap input, int colour, float tolerance) {
+        int width = input.getWidth();
+        int height = input.getHeight();
 
         int[] pixels = new int[width * height];
-        originalBitmap.getPixels(pixels, 0, width, 0, 0, width, height);
+        input.getPixels(pixels, 0, width, 0, 0, width, height);
 
         // We're working with a Stack-based approach of the Flood Fill algorithm to determine
         // the edges that should get removed.
         Stack<ImageCoordinate> coordinates = new Stack<>();
         // Start filling from the four corners of the image
-        coordinates.push(new ImageCoordinate(0, 0));
         coordinates.push(new ImageCoordinate(0, height - 1));
         coordinates.push(new ImageCoordinate(width - 1, height - 1));
         coordinates.push(new ImageCoordinate(width - 1, 0));
+        coordinates.push(new ImageCoordinate(0, 0));
+
+        int referenceRed = Color.red(colour);
+        int referenceGreen = Color.green(colour);
+        int referenceBlue = Color.blue(colour);
+        int sum = referenceBlue + referenceGreen + referenceRed;
+        float treshold = 3 * 255 * tolerance;
 
         while (!coordinates.isEmpty()) {
             ImageCoordinate current = coordinates.pop();
 
-            if (pixels[current.getY() * height + current.getX()] == colour) {
-                pixels[current.getY() * height + current.getX()] = Color.TRANSPARENT;
+            if (validPosition(current.getX(), current.getY(), width, height) && pixels[current.getY() * width + current.getX()] == colour) {
+                int pixel = pixels[current.getY() * width + current.getX()];
+                int red = Color.red(pixel);
+                int blue = Color.blue(pixel);
+                int green = Color.green(pixel);
+
+                float difference = Math.abs((red + blue + green) - sum);
 
-                // Reuse current ImageCoordinate-object.
-                current.setY(current.getY() + 1);
-                coordinates.push(current);
-                coordinates.push(new ImageCoordinate(current.getX(), current.getY() - 1));
-                coordinates.push(new ImageCoordinate(current.getX() + 1, current.getY()));
-                coordinates.push(new ImageCoordinate(current.getX() - 1, current.getY()));
+                if (difference <= treshold) {
+                    pixels[current.getY() * width + current.getX()] = Color.TRANSPARENT;
+
+                    // Reuse current ImageCoordinate-object.
+                    coordinates.push(new ImageCoordinate(current.getX() + 1, current.getY()));
+                    coordinates.push(new ImageCoordinate(current.getX() - 1, current.getY()));
+                    coordinates.push(new ImageCoordinate(current.getX(), current.getY() - 1));
+                    current.setY(current.getY() + 1);
+                    coordinates.push(current);
+                }
             }
         }
 
-        input.setPixels(pixels, 0, width, 0, 0, width, height);
+        Bitmap output = input.copy(input.getConfig(), true);
+        output.setHasAlpha(true);
+        output.setPixels(pixels, 0, width, 0, 0, width, height);
+
+        return output;
+    }
+
+
+    private boolean validPosition(int x, int y, int width, int height) {
+        return x >= 0 && x < width && y >= 0 && y < height;
     }
 }