Sunday, 11 December 2011

Video scaler

A video scaler is a accessory for converting video signals from one admeasurement or resolution to another: usually "upscaling" or "upconverting" a video arresting from a low resolution (e.g. accepted definition) to one of college resolution (e.g. aerial analogue television).

Video scaler accessories can be begin anchored in:

Computer monitors

Scan about-face devices


Video alteration and broadcasting equipment

Other audio/visual devices

Video scalers can additionally be a absolutely abstracted box, generally accouterment simple video switching capabilities. These units are frequently begin as allotment of home theatre or projected presentation systems. Home theatre uses ability accommodate converting a accepted analogue DVD or video bold arresting into high-definition for affectation on an LED, LCD or claret television while accepting the best angel affection possible. Scalers can additionally be begin in schools, address theatres and avant-garde churches, area abundant video sources (e.g. DVD video, alive camera feeds, DVI/VGA achievement from a computer) charge to be switched between, while the accomplished accessible resolution is maintained.

Video scalers are primarily a agenda device, about they can be accumulated with an analog-to-digital advocate (ADC, or digitizer) and a digital-to-analog advocate (DAC) to abutment analog inputs and outputs. One upscaling action that has gotten a lot of absorption is the IMAX DMR

Scaling a signal to match the display

The "native resolution" of a affectation is how abounding concrete pixels accomplish up anniversary row and cavalcade of the arresting breadth on the display's achievement surface. There are abounding altered video signals in use which are not the aforementioned resolution (neither are all of the displays), appropriately some anatomy of resolution adjustment (video scaling) is appropriate to appropriately anatomy a video arresting to a affectation device. For example, aural the United States, there are NTSC, ATSC, and VESA video standards anniversary with several altered resolution video formats.

Image artifacts/errors related to video scaling

Banding or posterization

Scaler ringing

Double ascent – When a antecedent accessory is acclimated which upscales to a resolution not built-in to a television's display, the TV can calibration the angel a additional time which unnecessarily reduces the final achievement quality.

Video processor

Video scalers are generally accumulated with added video processing accessories or algorithms to actualize a video processor that improves the credible analogue of video signals. These added accessories may accommodate the adeptness for:


aspect arrangement control

agenda zoom and pan

brightness/contrast/hue/saturation/sharpness/gamma adjustments

anatomy amount about-face and inverse-telecine

blush point about-face (601 to 709 or 709 to 601)

blush amplitude about-face (Component to RGB or RGB to Component)

mosquito babble reduction

block babble reduction

detail enhancement

bend enhancement

motion compensation

primary and accessory blush arrangement (including hue/saturation/luminance controls apart for each)

These can either be in dent form, or as a angle abandoned assemblage to be placed amid a antecedent accessory (like a DVD amateur or set-top-box) and a affectation with less-capable processing. The best broadly accustomed video processor companies in the bazaar as of June 2007 are:

Genesis Microchip (with the FLI chipset – was Genesis Microchip, STMicroelectronics completes accretion of Genesis Microchip on 01/25/08)

Sigma Designs (with the VXP chipset – was Gennum, Sigma Designs purchased the Image Processing accumulation from Gennum on February 8, 2008)

Integrated Accessory Technology (with the HQV chipset and Teranex arrangement articles – was Silicon Optix, IDT purchased SO on October 21, 2008)

Simplay Labs - Silicon Image (with the VRS chipset and DVDO arrangement articles - was Anchor Bay Technologies, Silicon Image purchased ABT on Feb 10, 2011)

All of these companies' chips are in accessories alignment from DVD upconverting players (for Standard Definition) to HD DVD/Blu-Ray Disc players and set-top boxes, to displays like plasmas, DLP (both advanced and rear projection), LCD (both flat-panels and projectors), and LCOS/”SXRD”. Their chips are additionally acceptable added accessible in angle abandoned accessories (see "External links" beneath for links to a few of these)