--- a/python/cvutils.py	Thu Mar 08 16:44:20 2018 -0500
+++ b/python/cvutils.py	Thu Mar 08 21:56:17 2018 -0500
@@ -318,14 +318,13 @@
                 lastFrameNum = float("inf")
             else:
                 lastFrameNum = lastFrameNumArg
-            if saveAllImages:
-                if nZerosFilenameArg is None:
-                    if lastFrameNumArg is None:
-                        nZerosFilename = int(ceil(log10(objects[-1].getLastInstant())))
-                    else:
-                        nZerosFilename = int(ceil(log10(lastFrameNum)))
+            if nZerosFilenameArg is None:
+                if lastFrameNumArg is None:
+                    nZerosFilename = int(ceil(log10(objects[-1].getLastInstant())))
                 else:
-                    nZerosFilename = nZerosFilenameArg
+                    nZerosFilename = int(ceil(log10(lastFrameNum)))
+            else:
+                nZerosFilename = nZerosFilenameArg
             while ret and not quitKey(key) and frameNum <= lastFrameNum:
                 ret, img = capture.read()
                 if ret: