Upconverting SD Video
Upconverting a 4:3 aspect ratio image to a 16:9 frame results in borders (or side panels)
on the left and right sides of the 4:3 image. This type of frame is sometimes referred to
as pillarboxed.
If the aspect ratios of the original and destination formats match (for example,
720 x 480 anamorphic footage upconverted to 1920 x 1080), you can simply scale
the original video to the destination size.