diff --git a/.gitignore b/.gitignore
index ddca0b6..083be28 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,4 +4,4 @@ pkg/
 .DS_Store
 dist/
 *.iml
-.idea
\ No newline at end of file
+.idea/
diff --git a/image-processor/src/lib.rs b/image-processor/src/lib.rs
index 8b1b41d..e95c154 100644
--- a/image-processor/src/lib.rs
+++ b/image-processor/src/lib.rs
@@ -1,6 +1,6 @@
+use image::imageops::FilterType;
 use image::{GenericImage, GenericImageView, Pixel, Rgba, RgbaImage};
 use photon_rs::PhotonImage;
-use image::imageops::FilterType;
 
 mod samples;
 
@@ -19,9 +19,19 @@ pub fn spiegel(photon_image: PhotonImage, median_kernelsize: u32, preview: bool)
     let i1 = RgbaImage::from_vec(width, height, raw_pixels).unwrap();
 
     let i2 = if preview {
-        image::imageops::resize(&i1, u32::min(500, width >> 1), u32::min(500, height >> 1), FilterType::Nearest)
+        image::imageops::resize(
+            &i1,
+            u32::min(500, width >> 1),
+            u32::min(500, height >> 1),
+            FilterType::Nearest,
+        )
     } else {
-        image::imageops::resize(&i1, u32::min(500, width), u32::min(500, height), FilterType::Nearest)
+        image::imageops::resize(
+            &i1,
+            u32::min(500, width),
+            u32::min(500, height),
+            FilterType::Nearest,
+        )
     };
     let mut i3 = imageproc::filter::median_filter(&i2, median_kernelsize, median_kernelsize);
     let i4 = if !preview {
@@ -80,16 +90,16 @@ fn fill(
                     let yy = y % height;
                     dest.unsafe_put_pixel(x, y, sample.unsafe_get_pixel(xx, yy));
                     src.unsafe_put_pixel(x, y, BLACK);
-                    if x > 1 {
+                    if x > 1 && src.unsafe_get_pixel(x - 1, y) != BLACK {
                         points.push(Coord(x - 1, y));
                     }
-                    if y > 1 {
+                    if y > 1 && src.unsafe_get_pixel(x, y - 1) != BLACK {
                         points.push(Coord(x, y - 1));
                     }
-                    if x < src.width() - 1 {
+                    if x < src.width() - 1 && src.unsafe_get_pixel(x + 1, y) != BLACK {
                         points.push(Coord(x + 1, y));
                     }
-                    if y < src.height() - 1 {
+                    if y < src.height() - 1 && src.unsafe_get_pixel(x, y + 1) != BLACK {
                         points.push(Coord(x, y + 1));
                     }
                 }
diff --git a/index.html b/index.html
index 77d6b10..24ac9f0 100644
--- a/index.html
+++ b/index.html
@@ -27,6 +27,7 @@
     <div id="slidecontainer" class="hide">
         <label for="slider">Brush stroke size</label><input type="range" id="slider" value="0" min="0" max="100" class="slider"/>
         <button id="apply">Apply</button>
+        <button id="reset" onclick="location.reload()">Reset</button>
     </div>
     </label>
     <div class="main-content">
@@ -36,6 +37,12 @@
             <canvas id="canvas" style="visibility: hidden;"></canvas>
         </div>
     </div>
+    <div id="clock-overlay">
+        <div class="clock">
+            <div class="hand hour-hand"></div>
+            <div class="hand minute-hand"></div>
+        </div>
+    </div>
 </div>
 <script>
     function allowDrop(event) {
diff --git a/src/css/styles.css b/src/css/styles.css
index d458907..162d389 100644
--- a/src/css/styles.css
+++ b/src/css/styles.css
@@ -69,6 +69,59 @@ li:hover {
     cursor: pointer;
 }
 
+#clock-overlay {
+    position: fixed;
+    top: 0;
+    left: 0;
+    width: 100%;
+    height: 100%;
+    background: rgba(255, 255, 255, 0.6);
+    display: none;
+    align-items: center;
+    justify-content: center;
+    z-index: 100;
+}
+
+#clock-overlay.visible {
+    display: flex;
+}
+
+.clock {
+    width: 80px;
+    height: 80px;
+    border: 6px solid #555;
+    border-radius: 50%;
+    position: relative;
+}
+
+.hand {
+    position: absolute;
+    bottom: 50%;
+    left: 50%;
+    transform-origin: bottom center;
+    border-radius: 4px;
+    background: #333;
+}
+
+.hour-hand {
+    width: 5px;
+    height: 22px;
+    margin-left: -2.5px;
+    animation: rotate 6s linear infinite;
+}
+
+.minute-hand {
+    width: 3px;
+    height: 30px;
+    margin-left: -1.5px;
+    animation: rotate 1s linear infinite;
+}
+
+@keyframes rotate {
+    from { transform: rotate(0deg); }
+    to   { transform: rotate(360deg); }
+}
+
 .slidecontainer {
     align-items: center;
     display: flex;
diff --git a/src/js/index.js b/src/js/index.js
index d0da36e..8791b29 100644
--- a/src/js/index.js
+++ b/src/js/index.js
@@ -10,11 +10,14 @@ let canvas,
 
 import("../../image-processor/pkg").then((module) => {
   const slider = document.querySelector("#slider");
-  let debounceTimer;
+  let debounceTimer = null;
   slider.oninput = (event) => {
     strokeSize = parseInt(event.target.value) / 5;
     clearTimeout(debounceTimer);
-    debounceTimer = setTimeout(() => filterImage(event, true), 200);
+    debounceTimer = setTimeout(() => {
+      debounceTimer = null;
+      filterImage(event, true);
+    }, 500);
   };
   slider.value = 0;
   const applyButton = document.querySelector("#apply");
@@ -24,16 +27,21 @@ import("../../image-processor/pkg").then((module) => {
   };
 
   function filterImage(event, preview) {
-    ctx.drawImage(sourceImage, 0, 0);
+    const overlay = document.querySelector("#clock-overlay");
+    overlay.setAttribute("class", "visible");
+    setTimeout(() => {
+      ctx.drawImage(sourceImage, 0, 0);
 
-    let rust_image = module.open_image(canvas, ctx);
-    const out = module.spiegel(rust_image, strokeSize, preview);
+      let rust_image = module.open_image(canvas, ctx);
+      const out = module.spiegel(rust_image, strokeSize, preview);
 
-    module.putImageData(canvas, ctx, out);
-    canvas.setAttribute(
-      "style",
-      `visibility:visible;position:absolute;top:${canvasTop}px`,
-    );
+      module.putImageData(canvas, ctx, out);
+      canvas.setAttribute(
+        "style",
+        `visibility:visible;position:absolute;top:${canvasTop}px`,
+      );
+      overlay.setAttribute("class", "");
+    }, 50);
   }
 });
 document.querySelector("#spieghel").src = spiegel;