diff --git a/README.md b/README.md
index 9d6a892..d60d1da 100644
--- a/README.md
+++ b/README.md
@@ -104,7 +104,7 @@ The default focal length is 5.7mm and this parameter can be modified using the a
 
 ## Webcam
 
-You can use the webcam as input by using the `--webcam` argument. By default the `--z_max` is set to 10 while using the webcam and the `--long_edge` is set to 144. If multiple webcams are plugged in you can choose between them using `--camera`, for instance to use the second camera you can add `--camera 1`.
+You can use the webcam as input by using the `--webcam` argument. By default the `--z_max` is set to 10 while using the webcam and the `--long-edge` is set to 144. If multiple webcams are plugged in you can choose between them using `--camera`, for instance to use the second camera you can add `--camera 1`.
 For example, the following command :
 ```
 python -m monoloco.run predict \
diff --git a/docs/webcam.gif b/docs/webcam.gif
index 58149e6..aa0a731 100644
Binary files a/docs/webcam.gif and b/docs/webcam.gif differ
diff --git a/monoloco/run.py b/monoloco/run.py
index 45fdf0d..ab2d060 100644
--- a/monoloco/run.py
+++ b/monoloco/run.py
@@ -27,7 +27,7 @@ def cli():
     predict_parser.add_argument('--hide_distance', help='to not show the absolute distance of people from the camera',
                                 default=False, action='store_true')
     predict_parser.add_argument('--dpi', help='image resolution', type=int, default=150)
-    predict_parser.add_argument('--long_edge', default=None, type=int,
+    predict_parser.add_argument('--long-edge', default=None, type=int,
                                 help='rescale the long side of the image (aspect ratio maintained)')
     predict_parser.add_argument('--white-overlay',
                                 nargs='?', default=False, const=0.8, type=float,
@@ -50,7 +50,7 @@ def cli():
     visualizer.cli(parser)
 
     # Monoloco
-    predict_parser.add_argument('--activities', nargs='+',
+    predict_parser.add_argument('--activities', nargs='+', choices=['raise_hand', 'social_distance'],
                                 help='Choose activities to show: social_distance, raise_hand')
     predict_parser.add_argument('--mode', help='keypoints, mono, stereo', default='mono')
     predict_parser.add_argument('--model', help='path of MonoLoco/MonStereo model to load')