Transform Domain

Guys what is 'Transform 开发者_如何学编程Domain' how to define it in images ?

Its a mathematical procedure done in data (usually, digital images or music) that converts it from one domain (time, for example) to another (frequency), usually doing Fourier's or Laplace's Transforms.

In the new Domain the data could be more easily handled, for lossy compression, de-noising, sharpening, etc. After edited, data is transformed back to its original domain.

In music, such Transforms are used for MP3 compression, by removing higher (and almost inaudible) frequencies that takes a lot of space.

In Images its mostly used for noise filters (sharpen, blur, etc) and Watermarking.

Transform Domain is another name for the Frequency Domain also known as Fourier Domain.

Transform Domain itself is not a mathematical procedure/function. However a function/procedure called Transform exits. Transform function/procedure is used to convert a digital image from the Spatial Domain to the Frequency Domain.

Now to define it in the context of images as you have asked: In in the Transform Domain, we can do image processing by changing the frequency components of an image. This reduces the computation cost of processing.

For detailed discussion of this topic, the primer used in CS is Digital Image and Processing by Gonzalez and Woods.