The Digital Fact Book - Quantel

Network layer(1) In TCP/IP, the network layer is responsible for accepting IP (Internet Protocol) datagramsand transmitting them over a specific network.(2) The third layer of the OSI reference model of data communications.NFSNetworkFile System. Developed by Sun Microsystems NFS allows sets of computers to accesseach other’s files as if they were locally stored. NFS has been implemented on many platformsand is considered an industry standard.See also: IPNibble8 binary bits = 1 Byte4 binary bits = 1 Nibble; geek humor!NLESee Nonlinear (editing)Noise (random)Irregular level fluctuations of a low order of magnitude. All analog video signals containrandom noise. Ideally for digital sampling, the noise level should not occupy more than oneLSB of the digital dynamic range. Pure digitally generated signals however do not containany noise – a fact that can be a problem under certain conditions.With digital compression, noise has a new importance. Noise, which can originate fromanalog sources, can be hard to distinguish from real wanted high frequency information.This means compression coders can waste valuable output bandwidth describing the noiseto the cost of the real pictures.See also: Dynamic RoundingNNon-additive mixA mix of two pictures which is controlled by their luminance levels relative to each other,as well as a mix value K (between 0 and 1): e.g. the position of a switcher lever arm. A and Bsources are scaled by factors K and 1-K but the output signal is switched to that which hasthe greatest instantaneous product of the scaling and the luminance values. The outputof any pixel is either signal A or B but not a mix of each. So if K = 0.5, in areas where pictureA is brighter than B then only A will be seen. Thus two clips of single subjects shot againsta black background can be placed in one picture.The term has also come to encompass some of the more exotic types of picture mixingavailable today: for example to describe a mix that could add smoke to a foreground picture– perhaps better termed an additive mix.See also: Digital mixing133