You may use Recordzilla to add watermark image (overlay) on the screen recording. This is useful to copyrighted your video, add your logo on the screen recording and so forth. Check Image under the Video Settings and click on Settings button to customize the watermark image.
Watermark image to be displayed on the screen recording.
You may select the value from 0 (invisible) to 255 (fully visible)
Any region of the image that contain this color will be transparent on the screen recording.
This area will preview the selected watermark image
The location where watermark image to be displayed