rdfs:comment
| - Monitor forma de onda (MFO), instrumento de medida utilizado en televisión para ver y medir la señal de vídeo. El monitor forma de onda o MFO es en realidad un osciloscopio especializado en la señal de televisión. Su base de tiempos está diseñada para adaptarse a los tiempos típicos de esa señal y ver las partes de interés de la misma de una forma fácil y sencilla. (es)
- Ein Waveformmonitor (WFM) ist ein spezielles Oszilloskop, das in der professionellen Videotechnik zum Messen von Videopegeln benutzt wird. Mit einem Waveformmonitor kann die Qualität eines Videosignals wesentlich besser beurteilt werden, als es auf einem Bildschirm oder Fernseher der Fall ist. Im Gegensatz zum Fernseh- oder Monitorbild, stellt ein Waveformmonitor die elektrische Spannung des Signals dar. (de)
- A waveform monitor is a special type of oscilloscope used in television production applications. It is typically used to measure and display the level, or voltage, of a video signal with respect to time. Waveform monitors are used for the following purposes: A waveform monitor is often used in conjunction with a vectorscope. Originally, these were separate devices; however modern waveform monitors include vectorscope functionality as a separate mode. (The combined device is simply called a "waveform monitor"). (en)
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has abstract
| - Ein Waveformmonitor (WFM) ist ein spezielles Oszilloskop, das in der professionellen Videotechnik zum Messen von Videopegeln benutzt wird. Mit einem Waveformmonitor kann die Qualität eines Videosignals wesentlich besser beurteilt werden, als es auf einem Bildschirm oder Fernseher der Fall ist. Im Gegensatz zum Fernseh- oder Monitorbild, stellt ein Waveformmonitor die elektrische Spannung des Signals dar. Das Spezifische an einem WFM gegenüber einem Standard-Oszilloskop ist die Horizontal- und die Vertikal-Darstellung der Videozeilen eines Bildes. Bei der Horizontal-Darstellung werden alle Zeilen übereinander dargestellt, das dient vor allem der Gesamtbeurteilung des Videopegels. Bei der Vertikal-Darstellung werden alle Zeilen eines Halbbildes nebeneinander angezeigt, wobei sich die Darstellungen beider Halbbilder überlagern. Damit lassen sich Signalfehler erkennen, die mit der Bildwechselfrequenz in Zusammenhang stehen, z. B. auch Brummstörungen bei analogen Signalen. Moderne Geräte bieten zusätzliche Messmöglichkeiten für digitale Videosignale. Die meisten in professionellen TV-Funkhäusern in Deutschland genutzten Waveformmonitore stammen vom amerikanischen Hersteller Tektronix. Haupteinsatzgebiet ist die Überwachung der Toleranzgrenzen von Luminanz und Chrominanz bei Videoproduktionen oder in Sendewegen. Außerdem dient der WFM zur Fehlersuche, z. B. bei Problemen mit speziellen Schaltsignalen in der Austastlücke bei analogen Fernsehsendungen, wie das Wide Screen Signalling zur automatischen in Zeile 23. (de)
- Monitor forma de onda (MFO), instrumento de medida utilizado en televisión para ver y medir la señal de vídeo. El monitor forma de onda o MFO es en realidad un osciloscopio especializado en la señal de televisión. Su base de tiempos está diseñada para adaptarse a los tiempos típicos de esa señal y ver las partes de interés de la misma de una forma fácil y sencilla. (es)
- A waveform monitor is a special type of oscilloscope used in television production applications. It is typically used to measure and display the level, or voltage, of a video signal with respect to time. The level of a video signal usually corresponds to the brightness, or luminance, of the part of the image being drawn onto a regular video screen at the same point in time. A waveform monitor can be used to display the overall brightness of a television picture, or it can zoom in to show one or two individual lines of the video signal. It can also be used to visualize and observe special signals in the vertical blanking interval of a video signal, as well as the colorburst between each line of video. Waveform monitors are used for the following purposes:
* To assist with the calibration of professional video cameras, and to "line up" multiple-camera setups being used at the same location in order to ensure that the same scene shot under the same conditions will produce the same results.
* As a tool to assist in telecine (film-to-tape transfer), color correction, and other video production activities
* To monitor video signals to make sure that neither the color gamut, nor the analog transmission limits, are violated.
* To diagnose and troubleshoot a television studio, or the equipment located therein.
* To assist with installation of equipment into a television facility, or with the commissioning or certification of a facility.
* In manufacturing test and research and development applications.
* For setting camera exposure in the case of video and digital cinema cameras. A waveform monitor is often used in conjunction with a vectorscope. Originally, these were separate devices; however modern waveform monitors include vectorscope functionality as a separate mode. (The combined device is simply called a "waveform monitor"). Originally, waveform monitors were entirely analog devices; the incoming (analog) video signal was filtered and amplified, and the resulting voltage was used to drive the vertical axis of a cathode ray tube. A circuit was used to isolate the sync pulses and colorburst from the video signal; the recovered sync information was fed to a which drove the horizontal axis. Early waveform monitors differed little from oscilloscopes, except for the specialized circuitry. Waveform monitors also permit the use of ; in this mode the sync and burst signals are taken from a separate input (thus allowing all devices in a facility to be genlocked, or synchronized to the same timing source). With the advent of digital television and digital signal processing, the waveform monitor acquired many new features and capabilities. Modern waveform monitors contain many additional modes of operation, including picture mode (where the video picture is simply presented on the screen, much like a television), various modes optimized for color gamut checking, support for the audio portion of a television program (either embedded with the video, or on separate inputs), eye pattern and jitter displays for measuring the physical layer parameters of serial-digital television formats, modes for examining the serial digital protocol layer, and support for ancillary data and television-related metadata such as timecode, closed captions and the v-chip rating systems. Modern waveform monitors and other oscilloscopes have largely abandoned old-style CRT technology as well. All new waveform monitors are based on a rasterizer, a piece of graphics hardware that duplicates the behavior of a CRT vector display, generating a raster signal. They may come with a flat-panel liquid crystal display, or they may be sold without a display, in which case the user can connect any VGA display. (en)
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