If your home theater movie collection includes a mix of DVDs and Blu-ray Discs, you may be wondering what the differences are between DVD quality and Blu-ray Disc quality. Here's a primer on DVD upscaling and how the results compare to Blu-ray.

The DVD format supports a native video resolution of 720 x 480 (480i). When you insert a disc into a DVD player, the player reads this resolution. Therefore, DVD is classified as a standard resolution format.

This worked well when the DVD format debuted in 1997, but DVD player manufacturers soon decided to improve DVD picture quality. They implemented additional processing on the DVD signal after it was read from the disc but before it reached the TV. This process is called progressive scan.

Progressive scan DVD players deliver the same resolution as other players, but provide a smoother picture.