diff --git a/yt_dlp/postprocessor/ffmpeg.py b/yt_dlp/postprocessor/ffmpeg.py
index 9dd50340a0..31e5aad4db 100644
--- a/yt_dlp/postprocessor/ffmpeg.py
+++ b/yt_dlp/postprocessor/ffmpeg.py
@@ -1211,19 +1211,19 @@ def __init__(self, info_dict, ffmpeg_args, hook_progress, ydl=None):
self._streams, self._stderr_buffer, self._stdout_buffer = ['', ''], '', ''
self._progress_pattern = re.compile(r'''(?x)
(?:
- frame=\s(?P\S+)\n
- fps=\s(?P\S+)\n
- stream_\d+_\d+_q=\s(?P\S+)\n
+ frame=\s*(?P\S+)\n
+ fps=\s*(?P\S+)\n
+ stream_\d+_\d+_q=\s*(?P\S+)\n
)?
- bitrate=\s(?P\S+)\n
- total_size=\s(?P\S+)\n
- out_time_us=\s(?P\S+)\n
- out_time_ms=\s(?P\S+)\n
- out_time=\s(?P\S+)\n
- dup_frames=\s(?P\S+)\n
- drop_frames=\s(?P\S+)\n
- speed=\s(?P\S+)\n
- progress=\s(?P