Pixel shifting

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Pixel shifting is a term used both for a method to prevent "burn-in" of static images on displays and as a method to augment resolution in digital imaging devices and projectors.

Pixel shift to avoid burn-in[edit]

Pixel shift for displays is a method to prevent static images (such as station bugs and video game HUD elements) from causing image retention and screen burn-in in susceptible display types such as plasma and OLED. The entire video frame is moved periodically (vertically and/or horizontally) so there are effectively no static images. One definition reads: "the image rotates in a circle in a way imperceptible to the viewer with a defined rhythm and pixel interval."[This quote needs a citation]

The firmware on some high end Samsung plasma TVs moves the video horizontally and vertically by some number of pixels every few minutes.[1] Some TVs allow the user to define the number of pixels moved and their interval. On Panasonic plasma TVs this technique is named Pixel Orbiter. Sony uses the term Pixel Shift for this technique in its OLED displays, while LG calls it Screen Shift.

Pixel shifting is sometimes used with other burn-in prevention methods like screensaver or power management functions.

Pixel Shift to increase resolution[edit]

Pixel shifting is also a technique that increases the true resolution of devices such as camcorder sensors and digital microscopes by moving one or more of the separate red, green or blue sensors by fractions of a pixel in the x- and y-directions.[2] For example, early high-definition camcorders used a 3CCD sensor block of 960 × 540 pixels each. Shifting the red and blue sensors half a pixel in both the vertical and horizontal direction permits the recovery of a 1920 × 1080 luminance signal. This technique is seeing a renaissance with native 1080p video projectors that pixel shift horizontally to produce an effectively 4K image on the screen. The electronics corporation JVC refers to it as "e-shift".

References[edit]

  1. ^ "Samsung Plasma, break in, burn in and image retention".
  2. ^ dvinfo.net discussion of pixel shifting