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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) Signal processing that compensates for a loss of detail caused by the aperture. It is a form of image enhancement adding artificial sharpness and has been used for many years.
b) Electrical compensation for the distortion introduced by the (limiting) size of a scanning aperture.
c) The properties of the camera lens, optical beam-splitting installation, and camera tube all contribute to a reduced signal at higher spatial frequencies generally falling off as an approximate (sin x)/X function.
Additionally, it is obvious in a scanning system that the frequency response falls off as the effective wavelength of the detail to be resolved in the image approaches the dimension of the scanning aperture and becomes zero when the effective wavelength equals the dimension of the scanning aperture. Aperture correction normally introduced in all video cameras restores the depth of modulation to the waveform at higher frequencies with the objective of flat response to 400 TV lines (in NTSC) for a subjective improvement in image quality.
Industry:Entertainment
In ADCs, aperture delay is the time from an edge of the input clock of the ADC until the time the part actually takes the sample. The smaller this number, the better.
Industry:Entertainment
The uncertainty in the aperture delay. This means the aperture delay time changes a little bit over time, and that little bit of change is the aperture jitter.
Industry:Entertainment
The available maximum dimensions of the optical image on the active surface of the photo-sensor, within which good quality image information is being recorded. The camera aperture determines the maximum usable scene information captured and introduced into the system, and available for subsequent processing and display. These dimensions are usually defined by standards. (Note: Not to be confused with lens aperture, which defines the luminous flux transmission of the optical path.)
Industry:Entertainment
The concept of a clean aperture in a digital system defines an inner picture area (within the production aperture) within which the picture information is subjectively uncontaminated by all edge transient distortions (SMPTE 260M). Filtrations for bandwidth limitation, multiple digital blanking, cascaded spatial filtering, etc., introduce transient disturbances at the picture boundaries, both horizontally and vertically. It is not possible to impose any bounds on the number of cascaded digital processes that might be encountered in the practical post-production system.
Hence, the clean aperture is defined to represent an acceptable (and practical) worst-case level of production.
Industry:Entertainment
The available maximum dimensions (mapped back into the camera aperture) for the system's ability to display good quality image information. The information available for display is usually cropped from the total captured by the cascade of tolerances that may be incorporated in the system, and also by intentional design features that may be introduced in the display.
Industry:Entertainment
A production aperture for a studio digital device defines an active picture area produced by signal sources such as cameras, telecines, digital video tape recorders, and computer-generated pictures.
It is recommended that all of this video information be carefully produced, stored, and properly processed by subsequent digital equipment. In particular, digital blanking in all studio equipment should rigorously conform to this specified production aperture (SMPTE 260M). The width of the analog active horizontal line is measured at the 50% points of the analog video signal. However, the analog blanking may differ from equipment to equipment, and the digital blanking may not always coincide with the analog blanking.
Industry:Entertainment
As defined by a test pattern, a safe action aperture indicates the safe action image area within which all significant action must take place, and the safe title image area, within which the most important information must be confined, to ensure visibility of the information on the majority of home television receivers. SMPTE RP 27.3 defines these areas for 35 mm and 16 mm film and for 2x2-inch slides.
Industry:Entertainment
An application runs in a module, communicating with the host, and provides facilities to the user over and above those provided directly by the host. An application may process the transport stream.
Industry:Entertainment
An integrated circuit designed for special, rather than general, applications.
Industry:Entertainment
