DVDs
The progressive output of a DVD player can be considered the baseline for EDTV. Movies shot at 24 frames-per-second (fps) are often encoded onto a DVD at 24 fps progressive, and most DVD players do the 2:2 or 3:2 pulldown conversion internally, before feeding the output to (usually) an interlaced display, or here, a progressive 576p or 480p.
The progressive 24 fps DVD will have a unifying effect on PAL and NTSC, just as film does, perhaps requiring conversion of the number of lines but without a conflict between field and frame rate. The player converts the video to the more-conventional video formats, on the fly, by simply repeating each field. It converts for PAL (referring here to 625 line 575 active line used with PAL as well as the chrominance aspects), by repeating each frame twice with a corresponding interlace, or for NTSC, by repeating some 480p frames 2 times and others 3 times (3:2 pulldown), to make 24 fps material play at 30fps, or 60 fields per second.
On an EDTV display, or on HDTVs in 480p mode, DVD players can display progressive disc content without needing to convert it to interlaced format. Various signal processing tricks are then used to fake the progressive scan; the quality of this depends on the quality of the upconversion process.
Blu-ray Disc and HD DVD formats can encode all EDTV forms, but because HDTV is a primary selling point of Blu-ray/HD DVDs, to date, this has been used only on certain bonus content.
Read more about this topic: Enhanced-definition Television