--- a/tracking.cfg	Tue Feb 17 15:32:29 2015 +0100
+++ b/tracking.cfg	Tue Mar 24 14:02:14 2015 +0100
@@ -37,21 +37,21 @@
 max-nfeatures = 1000
 # quality level of the good features to track
 feature-quality = 0.1
-# minimum distance between features
+# minimum distance between features (px)
 min-feature-distanceklt = 5
-# size of the block for feature characteristics
+# size of the block for feature characteristics (px)
 block-size = 7
 # use of Harris corner detector
 use-harris-detector = false
 # k parameter to detect good features to track (OpenCV)
 k = 0.4
-# size of the search window at each pyramid level
+# size of the search window at each pyramid level (px)
 window-size = 7
 # maximal pyramid level in the feature tracking algorithm
 pyramid-level = 5
 # number of displacement to test minimum feature motion
 ndisplacements = 3
-# minimum displacement to keep features
+# minimum displacement to keep features (px)
 min-feature-displacement = 0.05
 # maximum feature acceleration
 acceleration-bound = 3
@@ -70,11 +70,11 @@
 # minimum length of a feature (number of frames) to consider a feature for grouping
 min-feature-time = 20
 # Min Max similarity parameters (Beymer et al. method)
-# connection distance in feature grouping
+# connection distance in feature grouping (world distance unit or px)
 mm-connection-distance = 3.75
-# segmentation distance in feature grouping
+# segmentation distance in feature grouping (world distance unit or px)
 mm-segmentation-distance = 1.5
-# maximum distance between features for grouping
+# maximum distance between features for grouping (world distance unit or px)
 max-distance = 5
 # minimum cosine of the angle between the velocity vectors for grouping
 min-velocity-cosine = 0.8