framerate property
If your motion graphic asset is a .mov file, keep this setting unspecified. If your motion graphic asset is a series of .png files, specify the frame rate of the overlay in frames per second, as a fraction. For example, specify 24 fps as 24/1. Make sure that the number of images in your series matches the frame rate and your intended overlay duration. For example, if you want a 30-second overlay at 30 fps, you should have 900 .png images. This overlay frame rate doesn't need to match the frame rate of the underlying video.
Implementation
final MotionImageInsertionFramerate? framerate;