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Lucy...Can you 'esplain to me what exactly what upconverting is it and..

JohninTenn
06-02-2006, 08:47 AM
what does it do? It's hard for me to think it could be a better pic than I have now..

BobY
06-02-2006, 09:37 AM
Standard definiton DVD's have a typical resolution of 720 x 480 pixels.

HD has a typical resolution of 1920 x 1080 pixels (or 1280 x 720 pixels).

Just as with digital photography, a higher resolution picture looks sharper, more detailed and more realistic, especially when enlarged.

Upconversion digitally processes the SD image to add additional pixels boosting it to the number of pixels of an HD image.

I don't say it increases the resolution to that of an HD image because it doesn't. It uses interpolation (a sophisticated form of mathematical averaging) to synthesize new pixels based on the existing pixels. It essentially blends between the real pixels, giving the illusion of a higher resolution image, but it can't add detail or make the picture sharper. In fact, it usually softens the picture a bit as there is no way for the interpolator to distinguish between what is simply a transition between colors as a result of shading and a hard edge change of color. The interpolation will tend to smooth the transition of the hard edge, making the picture appear less sharp.

If you have a large-screen display, upconversion can help hide the blockiness and pixelation of SD material, but on a smaller screen the result may not be noticable at all, or worse, may make the image look less sharp than it would without the upconversion.

stchman
06-12-2006, 02:30 PM
Standard definiton DVD's have a typical resolution of 720 x 480 pixels.

HD has a typical resolution of 1920 x 1080 pixels (or 1280 x 720 pixels).

Just as with digital photography, a higher resolution picture looks sharper, more detailed and more realistic, especially when enlarged.

Upconversion digitally processes the SD image to add additional pixels boosting it to the number of pixels of an HD image.

I don't say it increases the resolution to that of an HD image because it doesn't. It uses interpolation (a sophisticated form of mathematical averaging) to synthesize new pixels based on the existing pixels. It essentially blends between the real pixels, giving the illusion of a higher resolution image, but it can't add detail or make the picture sharper. In fact, it usually softens the picture a bit as there is no way for the interpolator to distinguish between what is simply a transition between colors as a result of shading and a hard edge change of color. The interpolation will tend to smooth the transition of the hard edge, making the picture appear less sharp.

If you have a large-screen display, upconversion can help hide the blockiness and pixelation of SD material, but on a smaller screen the result may not be noticable at all, or worse, may make the image look less sharp than it would without the upconversion.
SD TVs are 640x480 interlaced. ED is 720x480 progressive. You wont notice any PQ differences in upconversion. It is mostly marketing.