Update app.py

app.py

@@ -94,7 +94,8 @@ def convert_video(video_file, quality, aspect_ratio, video_url, api_key, upload)
 
             ffmpeg_command = [
                 "ffmpeg", "-i", str(input_path), "-c:v", "libx264", "-crf", str(quality),
-                "-vf", f"scale={scale},setsar={aspect_ratio}", "-hls_time", "6",
+                "-vf", f"scale={scale}:force_original_aspect_ratio=decrease,pad=ceil(iw/2)*2:ceil(ih/2)*2,setsar={aspect_ratio}", 
+                "-hls_time", "6",
                 "-hls_playlist_type", "vod", "-f", "hls", str(output_path)
             ]