tune smaller patch

yaml/processor_visual_odometry.yaml

@@ -18,14 +18,14 @@ max_new_features: 30
 fast_params:
     # Threshold on the keypoint pixel intensity (in uchar [0-255]) 
     # the higher, the more selective the detector is
-    threshold_fast: 20
+    threshold_fast: 30
     # Avoids getting multiple keypoints at the same place
     non_max_suppresion: true
 
 # Lucas Kanade tracking parameters
 klt_params:
-    patch_width:      11
-    patch_height:     11
+    patch_width:      9
+    patch_height:     9
     nlevels_pyramids: 3
     klt_max_err:      0.3