Pyramid Generation
There are two main types of pyramids; lowpass pyramids and bandpass pyramids. A lowpass pyramid is generated by first smoothing the image with an appropriate smoothing filter and then subsampling the smoothed image, usually by a factor of two along each coordinate direction. This smoothed image is then subjected to the same processing, resulting in a yet smaller image. As this process proceeds, the result will be a set of gradually more smoothed images, where in addition the spatial sampling density decreases level by level. If illustrated graphically, this multi-scale representation will look like a pyramid, from which the name has been obtained. A bandpass pyramid is obtained by forming the difference between adjacent levels in a pyramid, where in addition some kind of interpolation is performed between representations at adjacent levels of resolution, to enable the computation of pixelwise differences.
Read more about this topic: Pyramid (image Processing)
Famous quotes containing the words pyramid and/or generation:
“So universal and widely related is any transcendent moral greatness, and so nearly identical with greatness everywhere and in every age,—as a pyramid contracts the nearer you approach its apex,—that, when I look over my commonplace-book of poetry, I find that the best of it is oftenest applicable, in part or wholly, to the case of Captain Brown.”
—Henry David Thoreau (1817–1862)
“One of the things that is most striking about the young generation is that they never talk about their own futures, there are no futures for this generation, not any of them and so naturally they never think of them. It is very striking, they do not live in the present they just live, as well as they can, and they do not plan. It is extraordinary that whole populations have no projects for a future, none at all.”
—Gertrude Stein (1874–1946)