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NTSC broadcasting describes a composite-video (where all three video carriers are matrixed together) signal that is hard-coded 480I (60 fields per second) and typically containing video encoded to be displayed in a 4x3 aspect ratio frame. And if the source was a movie with only 24 frames to start with, first those frames are split into 48 fields, and then the 3-2 pull-down is applied to turn those 48 fields per second into 60 fields per second before it leaves the broadcasting tower.
Laserdisc is a perfect example of an NTSC video device, as this final composite/480I 60 fields-per-second with 3-2 pull-down/4:3 video signal is recorded right onto the disc.
Well, a DVD doesn't have to be any of that.
DVDs can be encoded from component video sources, and in fact component video is what is stored on the disc. This means each of the three video signals (the black/white and two color difference channels) are recorded discretely on the disc and can be passed from the DVD player to the display in discrete component form as well, avoiding all the processing such as comb-filtering and color decoding that's an inherent part of the NTSC system.
Secondly, if a DVD is mastered from film, the video is stored on the disc in what are effectively the original 24 frames per second. The conversion from that image to a 60 field-per-second interlaced signal with the 3-2 pull-down is something that your DVD player does on the fly! This means that DVD players can be (and are) designed to provide a true 480 progressive image from film-source DVD software (DVDs can also be mastered from 60 fields-per-second 480I sources such as video cameras, in which case the DVD is 480I hard-coded and would require line-doubling to achieve 480P).
Thirdly, DVDs are not married to the 4:3 aspect ratio of NTSC television. They can be encoded as 16:9, which is the same aspect ratio of HDTV. This provides a 33% increase in vertical resolution to movies 1.78:1 or wider when viewed on a 16:9 compatible display by getting rid of or shrinking the letterboxing bars considerably (as many of you know, your DVD player is designed to take 16:9 video and down-convert it to 4:3 letterboxed if you're not 16:9 equipped). It's true that one could broadcast 16:9 anamorphic video over the NTSC system or record it on a laserdisc, but as these analog carriers have no built-in methodology for making these signals backwards-compatible for standard 4:3 TV viewers, I don't consider 16:9 to be a "feature" of the NTSC system.
These three qualifiers: Component video, 480 progressive, and option between 16:9 aspect ratio are actually mid-way up the DTV resolution spectrum. In fact, even DVDs that are hard-coded 480I containing 4:3 video are still within the DTV spec...albeit the lowest DTV specification. DVD software is not NTSC software, but really Standard Definition that can range from SD's lowest resolution to SD's highest resolution. When viewed in pure form on component video/480 progressive/16:9 capable displays in full resolution (bypassing all NTSC downconversion), today's DVDs deliver a picture that is dramatically superior to the very best NTSC presentation.