ITS: centralize ffmpeg logging

files affected:
  tests/scene4/test_preview_aspect_ratio_and_crop.py
  tests/scene4/test_preview_stabilization_fov.py
  tests/scene4/test_video_aspect_ratio_and_crop.py
  tests/sensor_fusion/test_preview_stabilization.py
  tests/sensor_fusion/test_video_stabilization.py
  utils/video_processing_utils.py

bug: 269360962
Change-Id: Iec9e060dd3864a1deaf8b1ca3c34927d716e0ae8
diff --git a/apps/CameraITS/utils/video_processing_utils.py b/apps/CameraITS/utils/video_processing_utils.py
index f19efa9..5717150c 100644
--- a/apps/CameraITS/utils/video_processing_utils.py
+++ b/apps/CameraITS/utils/video_processing_utils.py
@@ -50,8 +50,8 @@
 }
 
 
-def get_ffmpeg_version():
-  """Returns the ffmpeg version being used."""
+def log_ffmpeg_version():
+  """Logs the ffmpeg version being used."""
 
   ffmpeg_version_cmd = ('ffmpeg -version')
   p = subprocess.Popen(ffmpeg_version_cmd, shell=True, stdout=subprocess.PIPE)
@@ -59,7 +59,7 @@
   if p.poll() != 0:
     raise error_util.CameraItsError('Error running ffmpeg version cmd.')
   decoded_output = output.decode('utf-8')
-  return decoded_output.split(' ')[2]
+  logging.debug('ffmpeg version: %s', decoded_output.split(' ')[2])
 
 
 def extract_key_frames_from_video(log_path, video_file_name):