Version 1.0 of the Rviz Cinematographer consisted of the GUI and the View Controller.
In the GUI the user creates trajectories for the rviz camera.
CameraTrajectory messages are send to the View Controller moving the camera to the desired poses.
In Version 2.0 the Recorder was added to generate a video of what the user is seeing as a movement is requested and performed.
For that, the user specifies a set of recording parameters (file name of output video, fps, compression, watermark flag).
These are send right before the CameraTrajectory message to both the View Controller and the Recorder when a new movement is triggered.
The Recorder prepares a video file using the desired file path and codec (compression).
The View Controller switches into the recording mode, rendering and publishing the desired movement frame by frame at the requested frame rate.
The Recorder subscribes to and buffers the rendered images created by the View Controller.
It adds a watermark and feeds them into the video file.
As soon as the camera arives at the end of the trajectory (or the movement is canceled) the View Controller published a message to the Recorder indicating that rendering is finished and switches back to the regular mode.
The Recorder processes the remaining buffered images, releases the video file and notifies the GUI that recording is finished.