Re:A Pixel Is Not a Little Square (1995) [pdf]
by corysama on Sunday November 16, 2014 @01:30PM
(#8614951)
What is behind the pixel is an area. But, the pixel itself is a pinhole viewport into that area. This article is about resampling and reconstructing images that are already encoded as pixels (texels would be more accurate, but I don't know if that term was around back in 93).
So, when zooming in on a pixelated image, how do we fill in the gaps between the pinholes? Declaring pixels to be square areas means that larger views of a given image really should be composed of larger, hard-edged squares for each source pixel. I.e point sampling is truth.
The reality is that what's really between the pixel centerpoints is unknown --lost forever or never calculated at all. To fill in the gaps we can only make intelligent guesses. Therefore: sampling theory.
So, when zooming in on a pixelated image, how do we fill in the gaps between the pinholes? Declaring pixels to be square areas means that larger views of a given image really should be composed of larger, hard-edged squares for each source pixel. I.e point sampling is truth.
The reality is that what's really between the pixel centerpoints is unknown --lost forever or never calculated at all. To fill in the gaps we can only make intelligent guesses. Therefore: sampling theory.