So I'm watching a DVD (layer cake if you must know) on my macbook pro which has a 1200X800 resolution screen (and i must say lovely to look at), but the dvd itself looks a little "upscaled" and pixelated, so I'm gonna guess that DVD's don't have a very high resolution at all? I would thought it would have been larger that my diddly 13" screen though? And when i watch, say, a 720dp HD trailer of a film off the apple website, am I actually watching HD or just a very high resolution video? Thanks!
A PAL format [url= http://en.wikipedia.org/wiki/DVD_Video ]DVD Video[/url] is [i]usually[/i] stored as 720×576. So yeah - it will look a little stretched if you show it full screen on a 1200X800 display.
DVDs use standard PAL resolution, 720×576, which means your screen is having to guess the extra 480 horizontal pixels and 224 vertical pixels, so yes, some upscaling is going on.
As for the 720p trailers, I would guess that they're sending at the HD resolution (720 pixels high), but there's no guarantee that they're using a high bit-rate, which will also have an impact on the quality of the picture you're seeing.
As Graham says PAL (European mainly) DVDs are only 720x576 pixels, the video is inherently 4:3, 16:9 (widescreen) images are anamorphic and stretched out to an effective 1024x576 pixels so this will be upscaled to fit the screen of your Mac.
The Americans have it even worse as NTSC standard def video is only 720x480 pixels.
720p is the smaller of the 2 HD standards at 1280x720 pixels but it does have the advantage of being natively widscreen.
1080i or 1080p is the larger HD format at 1920x1080 pixels, this is the format that most Blu-Ray discs will be presented in.
I see. Thanks everyone!!
It'll also look more grey than it should, as apparently DVD players read any value <16 as black (legacy/compatibility with big scale projection etc), but almost all cheap/computer DVD players interpret that as a greyscale so your films will look more washed out than they should if properly set up.
