720x480 On A 320x240 Screen ?


720x480 is NTSC DVD resolution (16:9 or 4:3, it's actually the playback that determines 16:9 or 4:3 not the pixels). And I know that 720x480 doesn't make sense for either 16:9 or 4:3, but it's got something to do with non-rectangular pixels on tv's. Or something like that. EvilDragon will be able to give you a better answer as he does this kind of stuff for a living. I'm just remembering something I was trying to figure out last week when I was trying to convert a flash file to a widescreen dvd format ;).
 
a 720x480 picture is simply letter boxed on a regular TV sixed screen like the GP32 and X2, so there'd be black bars at the top and bottom whether it's a movie or a game (which I doubt anyone would actuvely code a game to be that resolution on a 340x240 handheld screen anyway, just a waste of memory.)

The best way to make a flash file 16:9 is simply to start with a 16:9 window from my own experiments, but for some reason in all my attempts 720x480 always gets cut on the edges to 704x480 or something.

It's not true anamorphic wide screen though (obviously) but it's easier to stretch it for a wide screen tv this way I beleive.
 
Either I really, REALLY fail at math, or 720x480 is 3:2.

Don't forget that there's full-res TV-output especially for movies (and possibly some emulators, e.g. CPS), too.
 
Saido posted on Sep 20 2005 at 09:20 PM said:
So can you also make games in a little bigger size that way?
It's hardware video decoding. Not sure you can use it to do anything with games. Anyway, why would you want to?

Alpha2 posted on Sep 20 2005 at 09:31 PM said:
The best way to make a flash file 16:9 is simply to start with a 16:9 window from my own experiments, but for some reason in all my attempts 720x480 always gets cut on the edges to 704x480 or something.
What we did was to create the flash file at 704x576 (576 as we're PAL here not NTSC), using graphics that were 1024x576 (16:9). Don't know why you squash the graphics down to 704x576 in flash - someone else was working on that as I was managing something else at the time. I think he said he found it in a pdf somewhere. Then we converted the swf to a 704x576 avi, then encoded the avi in tmpgenc as a 16:9 mpeg-2 which converted it to 720x576. A lot of steps, most of which don't make much sense to me, but the end result looked great :).

TandeM posted on Sep 20 2005 at 09:43 PM said:
Either I really, REALLY fail at math, or 720x480 is 3:2.
That's what I said. 720x480 is neither 4:3 or 16:9, but it can be both because of something to do with pixel sizes on tv's.
 
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Saido posted on Sep 20 2005 at 02:49 PM said:
But what if i want to make a game in 640x480?

Then you would have to plug it into the tv to see the aditional resolution, the gp2x screen is only 320x240. It will scale higher stuff down to fit on the screen though.
 
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yeah, when you playback those videos that are high res, they'll be downscaled to fit the 320x240 display.
also there's no point to make a 640x480 game unless you plan to play it on a higher res monitor and not on the handheld.

edit:
n/m, it's all been said :D
 
720x480 is NTSC DV, the format NTSC home camcorders are recording.
It is indeed 3:2.
Why? Because they just removed a few lines which are not visible (because TV's don't show all lines of a picture) to save bandwitdh (and improve the quality, 'cause, you know, DV is compressed)

And if you add the few lines (6, to be exact), you have 720x486, which is close enough (and has 4:3).

BTW: 3:2 = 4:2,7 which is pretty close to 4:3 :)

Oh, the Pixel Aspect Ratio also is important.
The 720x480 and 720x486 has a Pixel Aspect Ratio of 0.900, but LCD displays have a pixel Aspect Ratio of 1.
So, to have the same Frame Size 720x480 has on a television, you'd only need 720x432 pixels...

Complex? Yeah. :) But now you might get the idea why all emulators of TV consoles don't look the same on TFT displays - the Pixel Aspect ratio makes a bit of a difference.
 
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