codecVis: support DejaVu font on macOS

codec_visualizer/codecVis/__main__.py

@@ -7,6 +7,7 @@
 """
 
 import os
+import platform
 import sys
 import time
 import subprocess
@@ -55,6 +56,12 @@ def extract_frame(video_file, time_offset, output_file):
     subprocess.call(shlex.split(cmd),stdout=devnull, stderr=devnull)
 
 def get_font_path():
+    if platform.system() == "Darwin":
+        # Assume DejaVu to be installed in the user library
+        path = "~/Library/Fonts/DejaVuSans-Bold.ttf"
+        return os.path.expanduser(path)
+
+    # Default platform: Linux
     path = "/usr/share/fonts"
     files = glob.glob(path + "/**/DejaVuSans-Bold.ttf", recursive = True)
     return files[0]