DVD help

R

robertbiferi

banned
You know a DVD is 720x480 and even if it is a none widescreen DVD it still is 720x480 it just has a 4:3 ratio.

So let me gess the 720x480 resalotion is this high to make the picture Better?

Because standard TV is 640x480
 
The video size 720x480 is not larger than 640x480 to provide a better image. The size was arrived at for a number of reasons, mostly related to old TV.

DVD video is a fixed size, 720x480 for NTSC (North America) and 720x576 for PAL (Europe). The size remains the same regardless of whether the show is fullscreen (4:3), widescreen (16:9) or very widescreen (2.35:1). That is termed anamorphic. The dvd contains information that tells the player what size (aspect ratio) to stretch it to.

If the screen is say 1366x768, a fullscreen show will be stretched to 1024x768 (black bars on the sides), a widescreen show will be stretched to 1366x768, a very widescreen picture will be stretched to 1366x582, black lines top and bottom.

Note in the last one I said picture, not show. In almost every case, 2.35:1 shows are actually a 16:9 format with black bars already added top and bottom, the whole thing being stretched to 1366x768 (actual picture area will be 1366x582). Confusing isn't it?
 
I'm slightly confused when it comes to TV. I understood that standard digital TV used the same resolution as DVDs. I'm sure that's the case with PAL but I have read that NTSC is 640x480 as you have mentioned. I also read that standard digital TVs have rectangular pixels so the width of 720 is equivalent to 640 square pixels. The newer ATSC standard says that SDTV can be transmitted as 720x480. I cannot find a definitive answer, the variations are shown on this wiki page.

Yes, 720 is a bigger number than 640, but 720 smaller thingies can have the same width as 640 bigger thingies! My previous words on DVDs are correct to my knowledge.
 
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