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- Number of terms: 20560
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Tektronix provides test and measurement instruments, solutions and services for the computer, semiconductor, military/aerospace, consumer electronics and education industries worldwide.
A device used to modify a signal's noise characteristics. In video, noise gates provide optimal automatic suppression of snow (signal noise level). In audio, a noise gate provides a setable signal level threshold below which all sound is removed.
Industry:Entertainment
An electronic process used to reduce noise levels in audio and video. In video, the most effective noise reduction is accomplished by digitizing the video signal and carrying out a computerized pixel by pixel analysis of the data. In audio, the most effective systems employ an encode/decode scheme, performed before and after recording, such as the Dolby audio noise reduction system. Noise reduction can be performed on an existing audio signal using systems such as DNR (dynamic noise reduction) but are less effective because they also affect the audio signal.
Industry:Entertainment
An MPEG encoding method using a predictive algorithm to take into account information that is common among adjacent frames. P frames predict the difference between the current frame and the closest preceding I or P frame to minimize the amount of data that needs to be coded for each frame. P frame encoding is used in conjunction with I and B frame encoding.
Industry:Entertainment
All production work done after the raw video footage and audio elements have been captured. Editing, titling, special effects insertion, image enhancement, audio mixing and other production work is done during post-production. Videonics equipment is ideally suited for use in post-production.
Industry:Entertainment
Region Coding has received attention because of the ease with which it can be decoded and the fact that a coder of this type is used in Intel's Digital Video Interactive system (DVI), the only commercially available system designed expressly for low-cost, low-bandwidth multimedia video. Its operation is relatively simple. The basic design is due to Kunt. Envision a decoder that can reproduce certain image primitives well. A typical set might consist of rectangular areas of constant color, smooth shaded patches and some textures. The image is analyzed into regions that can be expressed in terms of these primitives. The analysis is usually performed using a tree-structured decomposition where each part of the image is successively divided into smaller regions until a patch that meets either the bandwidth constraints or the quality desired can be fitted. Only the tree description and the parameters for each leaf need then be transmitted. Since the decoder is optimized for the reconstruction of these primitives, it is relatively simple to build. To account for image data that does not encode easily using the available primitives, actual image data can also be encoded and transmitted, but this is not as efficient as fitting a patch. This coder can also be combined with prediction (as it is in DVI), and the predicted difference image can then be region coded. A key element in the encoding operation is a region growing step where adjacent image patches that are distinct leaves of the tree are combined into a single patch. This approach has been considered highly asymmetric in that significantly more processing is required for encoding/analysis than for decoding. It is harder to grow a tree than to climb one. While hardware implementations of the hybrid DCT coder have been built for extremely low bandwidth teleconferencing and for hdtv, there is no hardware for a region coder. However, such an assessment is deceptive since much of the processing used in dvi compression is in the motion predictor, a function common to both methods. In fact, all compression schemes are asymmetric, the difference is a matter of degree rather than one of essentials.
Industry:Entertainment
A measure of the ability to reproduce detail. Generally, referred to as horizontal resolution and evaluated by establishing the number of horizontal lines which are clearly discernible on a test pattern. Resolution specifications are not very well standardized, especially as stated in connection with monitors. Using the rule of thumb of 80 lines per MHz of bandwidth, VHS and 8mm typically achieves 240 lines of resolution, S-VHS and Hi-8 achieve 400, broadcast achieves 330.
Industry:Entertainment
Any photographic process in which an image is produced by secondary development of the silver halide grains that remain after the latent image has been changed to silver by primary development and destroyed by a chemical bleach. In the case of film exposed in a camera, the first developer changes the latent image to a negative silver image. This is destroyed by a bleach and the remaining silver halide is converted to a positive image by a second developer. The bleached silver and any traces of halide may now be removed with hypo.
Industry:Entertainment
With respect to Indeo(TM) video technology, it is a playback format that can determine the playback capabilities of the computer on which it is playing. Using this information, it allows video playback to take advantage of high-performance computer capabilities while retaining the ability to play on a lower performance computer.
Industry:Entertainment
A device designed to generate special effects. The simplest devices process a single video signal, change its color, generate sepia tones, invert the picture to a negative, posterize the image and fade or break up the image into various patterns. More sophisticated equipment uses several video sources, computer-generated graphics and sophisticated animation with digital effects.
Industry:Entertainment
An instrument with which a photographic emulsion is given a graduated series of exposures to light of controlled spectral quality, intensity, and duration. Depending upon whether the exposures vary in brightness or duration, the instrument may be called an intensity scale or a time scale sensitometer.
Industry:Entertainment
