From Digital Video and HDTV Algorithms and Interfaces

Chapter List

Appendix A: YUV and Luminance Considered Harmful
Appendix B: Introduction to Radiometry and Photometry

This is a plea for precise terminology. The notation YUV, and the term luminance, are widespread in digital video. In truth, digital video almost never uses Y?UV color difference components, and never directly represents the luminance of color science. The common terms are almost always wrong. This note explains why. I urge video engineers and computer graphics specialists to use the correct terms, almost always Y ?C B C R and luma.

Cement vs. Concrete

I'll demonstrate by analogy why it is important to use correct terms. Next time you're waiting in line for a bus, ask the person next to you in line what building material is used to construct a sidewalk. Chances are that person will answer, "cement."

The correct answer is concrete. Cement is calcined lime and clay, in the form of a fine, gray powder. Cement is one ingredient of concrete; the other ingredients are sand, gravel, and water.

In an everyday situation, you need not be precise about which of these terms are used: If you refer to a sidewalk as being constructed of "cement," people will know what you mean. Lay people are not confused by the term cement. Interestingly, experts are not confused either. If a construction superintendent yells out to his foreman, "Get me 500 pounds of cement!" the foreman understands immediately from context...

Copyright Elsevier Inc. 2003 under license agreement with Books24x7

Products & Services
Concrete Blocks and Cement Blocks
Concrete blocks and cement blocks are preformed, manufactured concrete structures that are ready for on-site installation. They are manufactured, cast, and cured in factories or other production facilities.
Cement Boards
Cement boards are combinations of cement, glass, aggregate, and fiber reinforcements that are formed into sheets and used as tile backing boards, and to build wall or floors.  
Specialty Cement, Concrete, and Mortar
Specialty cement, concrete and mortar contain specialized binders such as K silicate, calcium aluminate, sulfur, and oxysulfate or polymer resins. They cure or set through film drying (air setting), chemical reactions, thermoset bonds, hydraulic bonds, hot melting, and multiple component binder systems.
Hydraulic and Portland Cement
Hydraulic and Portland cement products have a calcium silicate binder. They are often used to build and repair concrete or masonry structures.
Cement, Concrete, and Mortar
Cement, concrete and mortar are polymer or cement-based binders, compounds or aggregate mixtures for joining components and forming structures.

Topics of Interest

Overview Nonlinear coding of luminance is essential to maximize the perceptual performance of an image coding system. This chapter introduces luminance and lightness, or what is loosely called...

Overview Note Luminance is proportional to intensity. For an introduction to the terms brightness, intensity, luminance, and lightness, see page 11. In photography, video, and computer graphics,...

Overview Although not exactly "digital" video, the NTSC and PAL composite color video formats are currently the most common formats for video. Although the video signals themselves are analog, they...

Overview The Commission Internationale de L' clairage (CIE) has defined a system that maps a spectral power distribution (SPD) of physics into a triple of numerical values-CIE XYZ tristimulus values...

4.1 Historical Perspective 4.1.1 Introduction At its simplest, concrete is an artificial stone made of three ingredients: aggregate, cement, and water. The aggregate components, coarse and fine, are...