Update app.py

app.py

@@ -9,8 +9,8 @@ w2 = os.path.join(os.path.dirname(__file__), "files/hf-logo.png")
 def generate_video(original_video, watermark):
     return gr.Video(original_video, watermark=watermark)
 
-
-demo = gr.Interface(generate_video, [gr.Video(), gr.Image(type='filepath')], gr.Video(),
+# Use RGBA image mode to preserve transparency for png images.
+demo = gr.Interface(generate_video, [gr.Video(), gr.Image(type='filepath', image_mode='RGBA')], gr.Video(),
                     examples=[[a, w1], [b, w2]])
 
 if __name__ == "__main__":