VGA -> NTSC. I hate scanlines.

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Ok, I made a 320 by 240 image. (that is the right resolution, right?) and it looks like crap when i put it on a TV. Any suggestions on how to make this better quality?
 
No, it's not the right resolution.

NTSC runs at 640x480, IIRC. PAL runs at 720x540.

320x240 is exactly half 640x480 so on NTSC it wouldn't be too bad ... but why not use 640x480?
 
Fice is right about PAL, but wrong about NTSC.

NTSC (The USA's TV format) is 720x486. Trust me, I know. This is one of my main fields of expertise.

Sephiroth 3D

"I don't understand..." "You don't have to understand." - Final Fantasy: The Spirits Within

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[edited] 135 2002-02-01 00:56
 
Oh, we're including extra parts of the frame? I thought the "useful" (ie. always visible part) of NTSC was 640x480 ... well, anyway, 720x540 is the "useful" resolution of PAL but the frame itself is larger - I can capture video at up to 768x576 easily, and I believe it technically goes larger still than that although you can't really use it for much since it's not generally visible.
 
Hmm ... don't know whether I can define custom resolutions as such, but the current Radeon drivers support "extra" resolutions intended for DVD playback. I can select 848x480 (widescreen) in display properties, and I'm sure I had others available in the past. I suspect it depends on what outputs I'm running; currently with two monitors connecting, it doesn't seem to support as many "strange" resolutions as when I have the TV out enabled with only one (or no) monitors ;)

Must check that out really.
 
Your best bet for DVD on a computer screen would be 1280x960. Since most DVD software does the anamorphic trick that Sony Wega TV's do, you get enhanced resolution for anamorphic DVDs, even though they are still letterboxed.

Or use Dscaler ( http://www.dscaler.com ). A de-interlacer for BT8x8 TV cards. Very nice program(open source as well). Looks very nice with Svideo input from a set top DVD player, and has auto calibration for THX Optimode and other setup discs.


As for the original post, TV's are interlaced, so there is no way around that(other than HDTV).
 
A "Frame" of TV images consists of 2 "Fields". The TV will display one field, and then the other. This process is known as "interlacing frames". This allows for a more fluid motion perceived by the TV sets.

To imitate interlacing frames, computers will add lines of black a single pixel tall to an image, giving the impression of interlacing frames.

Sephiroth 3D

"I don't understand..." "You don't have to understand." - Final Fantasy: The Spirits Within

Sephiroth 3D.com
[email protected]
 
On 2002-02-01 22:29, Sephiroth 3D wrote:
A "Frame" of TV images consists of 2 "Fields". The TV will display one field, and then the other. This process is known as "interlacing frames". This allows for a more fluid motion perceived by the TV sets.
Click to expand...
Actually, this is done to save video "bandwidth". The first developers of interlaced television sets saw they could cut their bandwidth requirements in half by sending half of the lines in one burst, then half in another.
 
Nope. If you're sending 625 lines, you're sending 625 lines no matter whether you send odd then even lines or send them all in order. The reason is that originally, TV's couldn't refresh very well. At only 25 frames per second (normal PAL, say) if you drew the whole frame in order, then you'd see a visible refresh because by the time you'd drawn the bottom of the screen, the top part would've lost the glow and faded somewhat, so the start of the next frame would be very noticable - a sudden brightening. By alternating lines, then you aren't updating a large "block" at once, so it doesn't seem to flicker so much.
 
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