In this chapter, we show some image processing applications that use the spectral framework. These are related to denoising, texture processing, enhancement, and image fusion. This area is currently investigated and developed. A main theme is that following the image decomposition one can use very basic operations of attenuating, enhancing, and mixing certain spectral bands. Thus, a single framework with a solid theory can have very diverse applications, similar to classical linear transforms. The aim here is to give several interesting examples and to show the potential of using the nonlinear spectral formulations.