avoid division by 0

pandora/archive/extract.py

@@ -317,6 +317,7 @@ def average_color(prefix, start=0, end=0):
 
     if end:
         frames = end - start
+    if frames:
         for i in range(0, len(pixels)):
             p = np.sum(pixels[i], axis=0) / frames
             color += p

pandora/clip/managers.py

@@ -59,6 +59,9 @@ def parseCondition(condition, user):
             return ~q
         else:
             return q
+    if (not exclude and op == '=' or op in ('$', '^', '>=', '<')) and v == '':
+        return Q(True)
+
     if k.endswith('__id'):
         v = decode_id(v)
     if isinstance(v, bool): #featured and public flag