A Pixel Is Not A Little Square (1995) [pdf]

I imagine this came up partly as a result of the recent alpha compositing discussion. We desperately need some research, based in user studies and using modern display technology, to settle some basic questions: * What reconstruction filter gives the best results? Is it the same for vector (text) and natural images? By "best" I do mean contrast (sharpness) and lack of visible artifacts. * For rendering of very thin lines (relevant to text), what gamma curve gives the perception…

A little bit of background for the paper and a brief summary might be beneficial: The author is Alvy Ray Smith. He's one of the pioneers of computer graphics (http://en.wikipedia.org1/wiki/Alvy_Ray_Smith). As the author states in the introduction: "If you find yourself thinking that a pixel is a little square, please read this paper." To get from the point to the squares -interpretation you need to read a little bit forwards: "Sampling Theorem tells us that we can reconstruct a continuous…

Is this not outdated? It uses examples of how pixels on scanners, printers, and CRT monitors are not squares. Fair enough. Back when this was written, one could very reasonably argue that pixels were intended to be point samples with a convolution. But modern pixels on most LCD screens certainly are exceedingly crisp squares (with subpixels), and processing RAW camera sensor data, antialiasing techniques, and image resampling seems to "mostly" assume that pixels do represent the average color over a…

If you’re wondering what it’s talking about when it says the triads of red/green/blue rectangles on a CRT display don’t correspond to pixels, here’s a Technology Connections video that explains it: https://youtu.be/Ea6tw-gulnQ But on an LCD, the display really is made up of a bunch of solid-colored rectangle-ish shapes, and if the LCD is using standard RGB pattern, each red/green/blue triplet does correspond to one pixel. So if you zoom in, “a pixel is a little square” is very close…