to make it easier on the processing, on things like camera phones. Also most (consumer) video cameras work this way now. The whole image is not exposed at once, but from top to bottom in strips: another good visual here
"Capitalization is the difference between helping your Uncle Jack off a horse, and helping your uncle jack off a horse." "'she' also likes to swap since I think I am going to need to give her to woody again." - Dvlhntr "full alphabetic boost mode" - ChristopherTheOne "Two oil eating, angry, spinning triangles of death." - turtleboy on rotary engines "You're the Skrillex of Z32s." BradX (UF)