Originally Posted by cavu
This message is not intended to confuse the OP ... it is a nitpick.
And I'm going to correct your nitpick.
SD-DVDs are recorded on the media as 720x480 but they are NEVER displayed that way.
This is true for NTSC. It is 720x576 for PAL.
the 720x480 SD-DVD pixels are not square - they are rectangular.
Yep, this is also true.
On 4:3 content, the 720x480 pixels are narrower than they are tall and are converted to 640x480 square pixels.
Here is where the correcting starts. The 720 pixels are not "converted" to 640 pixels. Under normal operation the 704 center pixels are DtoA (digital to analog) converted to the NTSC active video area of the 63.5 microsec NTSC analog scan line. Some players might do all 720, but various things I've read point to it being the center 704 or all 720. Keep in mind that the DVD standard even supports 544 pixels (or some value in that range) width DVDs. Whatever it is, it is just DtoA'd to fit in the NTSC (or PAL) active video area of the scan line.
On 16:9 content, the 720x480 pixels are taller than they are wide and are converted to 854x480 square pixels.
Again, no conversion. Because NTSC/PAL widescreen is really anamorphic widescreen, the same 720/704 pixels are DtoA'd to the NTSC/PAL active video area of the scan line. The widescreen display, does the stretching to fill the width of the screen.
The native output of a SD-DVD player is 480i