Bebop Coordinate System Conventions

I want to compute the linear/angular velocity in the camera frame of the bebop (Pin Hole camera convention) but it is quite confusing :face_with_raised_eyebrow::face_with_raised_eyebrow: because Here they say that (I quote)

This message contains both the position and velocity of the Bebop in an ENU aligned odometery frame also named as odom

but in the coordinate convention ( ROS Standard Message Types (i.e Twist, Odometery) - REP 103) given in here There is no ENU coordinate!!!

So am not sure which coordinate convention they are using to represent the Linear/Angular Velocity and the pose of the Bebop!!

Please any help would be appreciated. Thanks