ar_track_alvar not detecting anything ROS Melodic, no kinect, single tag.

edit

I am using ar_track_alvar package to track single marker without kinect. But empty list is published on /ar_pose_marker no matter how much I increase max_track_error.

Steps I followed:

1. roslaunch usb_cam usb_cam-test.launch
2. rosrun tf2_ros static_transform_publisher 0 0 0 0 0 0 1 /map /usb_cam

3. Final launch file.

       <launch>
   
       <arg name="marker_size"          default="5.0" />
       <arg name="max_new_marker_error" default="0.05" />
       <arg name="max_track_error"      default="0.05" />
   
       <arg name="cam_image_topic"      default="/usb_cam/image_raw" />
       <arg name="cam_info_topic"       default="/usb_cam/camera_info" />
       <arg name="output_frame"         default="/map" />
   
       <node name="ar_track_alvar" pkg="ar_track_alvar" type="individualMarkersNoKinect" respawn="false" output="screen">
           <param name="marker_size"           type="double" value="$(arg marker_size)" />
           <param name="max_new_marker_error"  type="double" value="$(arg max_new_marker_error)" />
           <param name="max_track_error"       type="double" value="$(arg max_track_error)" />
           <param name="output_frame"          type="string" value="$(arg output_frame)" />
   
           <remap from="camera_image"  to="$(arg cam_image_topic)" />
           <remap from="camera_info"   to="$(arg cam_info_topic)" />
       </node>
   </launch>
   

Any ideas? Thanks!