trying to optimize hls download

app.py

@@ -398,7 +398,7 @@ with gr.Blocks(theme='WeixuanYuan/Soft_dark') as demo:
     #                ]
 
     gr.Examples(examples=[
-                        ['https://hiemdall-dev2.azurewebsites.net/api/playlist/rec_rd2FAyUo/vod', '2600', '2630'],
+                        ['https://hiemdall-dev2.azurewebsites.net/api/playlist/rec_rd2FAyUo/vod', '0', '30'],
                         #[os.path.join(os.path.dirname(__file__), "files", "train14.mp4")],
                         #[os.path.join(os.path.dirname(__file__), "files", "train_17.mp4")],
                         #[os.path.join(os.path.dirname(__file__), "files", "train13.mp4")],

hls_download.py

@@ -13,7 +13,7 @@ def download_clips(stream_url, out_dir, start_time, end_time, resize=True):
     output_file = os.path.join(out_dir, f"train_{len(os.listdir(out_dir))}.mp4")
     # output video at 30fps
     if resize:
-        subprocess.run(['ffmpeg', '-i', stream_url, 
+        subprocess.run(['ffmpeg', '-f', 'hls', '-i', stream_url, 
                         '-ss', str(start_time - 2), 
                         '-to', str(end_time + 2),  # pad end time by a couple of seconds
                         '-r', str(30), 
@@ -23,7 +23,7 @@ def download_clips(stream_url, out_dir, start_time, end_time, resize=True):
                         '-vf', 'scale=-2:360',
                         '-c:a', 'copy', output_file])
     else:
-        subprocess.run(['ffmpeg', '-i', stream_url, 
+        subprocess.run(['ffmpeg', '-f', 'hls', '-i', stream_url, 
                         '-ss', str(start_time - 2), 
                         '-to', str(end_time + 2),  # pad end time by a couple of seconds
                         '-r', str(30),