fix comparison & readme

README.md

@@ -20,11 +20,19 @@ and the slot machine effect ([2]) further promotes harmful sedentary lifestyle.
 
 Weihua is social media of the new age. 
 Combining many features of the apps young people enjoy, it is created with wellbeing of its users at the core. 
-Weihua is a fun 
 
-## Implementation
+Weihua is a fun way to challenge yourself and your friends, while learning some moves to show off at a party later, 
+together with your friend group. Every day there are 5 new challenges of different difficulty, which you can try to complete.
+You will see how well you managed to reproduce the dance, and compete against your friends and people in your country 
+(within your difficulty level). No users are able to see others' videos, only scores. 
+
+Key features include
 
-## References
+- watching the dance challenge and recording your own attempt in the app
+- scoring of how well your dance matches the dance in today's challenge
+- leaderboard within your friend group for the current day 
+
+## Implementation
 
 
 [1]: https://www.who.int/news/item/22-11-2019-new-who-led-study-says-majority-of-adolescents-worldwide-are-not-sufficiently-physically-active-putting-their-current-and-future-health-at-risk

backend/yolo_model/comparison.py

@@ -17,6 +17,8 @@ def _frames_to_movements(frames):
     # all relative to upper left corner of the bounding box
     movements = [[] for _ in range(0, 17)]
     for frame in frames:
+        if not frame:
+            continue
         frame = frame[0]  # first person in the frame
         for i in range(0, 17):
             x = frame['keypoints']['x'][i]