Using adobe premiere pro to adjust the opacity of an image allows the user to create a watermark or fade an image out of a scene.
Importing the video and image file:
Using Windows Explorer, browse to the selected files and drag them into the project window as depicted above.
Drag the video file and image file into the timeline.
Positing the text to the desired location using the Selection tool
Select, File> Window and select Effect Controls
With the Image Layer selected, the effect panel below becomes accessible.
Change the Opacity setting to your preference.