When you add a movie to the InDesign document, the movie object and poster appear in a frame. When you export to PDF, the movie object’s boundary determines the size of the movie in the PDF document, not the frame size or poster size.
For best results, keep the poster size and dimension the same as the movie. If you apply a clipping path or resize the image, the exported PDF document may not include these changes.
To resize the movie object, poster, and
frame, use the Scale tool and
drag one of the corner handles (hold down Shift to maintain proportions).
To resize only the frame, use the Selection tool to
drag a corner handle.
To resize the poster or media object, use the Direct
Selection tool to
select the poster. Switch to the Selection tool, and then drag a
corner handle.