Update app.py

app.py

@@ -102,8 +102,9 @@ def fourier_transform_drawing(input_image, frames, coefficients, img_size, blur_
         w, h = canvas.get_width_height()
         buf = np.frombuffer(canvas.buffer_rgba(), dtype=np.uint8)
         image = Image.fromarray(buf.reshape(h, w, 4), 'RGBA').convert('RGB')
+        last_image = image
         
-        return (image, None)
+        yield (last_image, None)
 
     # Generate and yield images for each frame
     time = np.linspace(0, 1, num=frames)