High Dynamic Range (HDR) displays are typically formed from the optical combination of a Liquid Crystal Display (LCD) panel, and an array of individually controlled Light Emitting Diodes (LEDs) disposed behind the LCD panel. Pixel intensities are typically not controlled independently of each other because each LED overlaps many LCD pixels, and contributes to the brightness of the image displayed. In an HDR display, the contrast at the LCD panel is multiplied with the contrast at the array of LEDs, the result usually exceeding contrast ratios of 100,000:1.
Generally, common techniques to generate HDR images cause perceptual differences between the input image and the viewed image. While functional, various conventional approaches have drawbacks. In some approaches, common iterative solver algorithms have been used to calculate the set of LED driving intensities by solving a system of equations. Typical iterative solver algorithms process a relatively large number of pixels in the input image. As the number of pixels are greater than the number of LEDs, iterative solver algorithms often produce out-of-range values, and generate non-linear responses that led to abrupt changes in the light emitted by the array of LEDs between image frames. Such abrupt changes might result in a perceptible error. Conventional iterative solvers also attempted to prevent abrupt contrast in light emitted by the array of LEDs by focusing on edge-sharpening that might occur between image frames. But in doing so, these approaches have been complicated as they seek to solve for an ideal, “target” image at the array of LEDs.
In view of the foregoing, it would be desirable to provide systems, computer-readable mediums, methods and apparatuses to operate an array of LEDs of a HDR display by, among other things, controlling backlight illumination and LEDs as a function of an input image.