Embodiments of the disclosure relate to a compensation device of luminance uniformity and a controlling method thereof, more particularly, to a technology of predicting a level of maximum luminance value that is changed in compensating luminance uniformity of an image displayed on a display apparatus and providing it to a user. A compensation device of luminance uniformity according to an embodiment includes a data acquirer configured to acquire a luminance value of an image displayed on a display apparatus; a controller configured to determine a maximum luminance value and a minimum luminance value among the acquired luminance values, and determine luminance uniformity of the minimum luminance value based on the maximum luminance value, and determine a change amount of the maximum luminance value to be adjusted in order to change the determined luminance uniformity; and a display configured to display the change amount of the maximum luminance value adjusted to change the luminance uniformity, and the luminance uniformity that is changed in response to the change amount of the maximum luminance value.

A driving method of a display device including a power source which supplies a power voltage to a power base line, and pixels connected to power branch lines commonly connected to the power base line, includes calculating a first scale factor based on input grayscales received during a first frame period; calculating first output grayscales by applying the first scale factor to first input grayscales received during a second frame period, where the second frame period is a frame period immediately next to the first frame period; displaying an image by at least a part of the pixels based on the first output grayscales; and providing a first current limiting signal to the power source and calculating a second scale factor smaller than the first scale factor when a current of the power base line exceeds a reference value.

Raw grayscale image data, representing images to be displayed in successive frames, is used to drive a display having pixels that include a drive transistor and an organic light emitting device by dividing each frame into at least first and second-frames, and supplying each pixel with a drive current that is higher in the first sub-frame than in the second sub-frame for raw grayscale values in a first preselected range, and higher in the second sub-frame than in the first sub-frame for raw grayscale values in a second preselected range. The display may be an active matrix display, such as an AMOLED display.

The present disclosure generally relates to a method and device for inverse-tone mapping a picture. The method comprising: —obtaining (20) a first component (Y) comprising: —obtaining a luminance component (L) from said color picture; —obtaining a resulting component by applying (20), a non-linear function on said luminance component (L) in order that the dynamic of the resulting component is increased compared to the dynamic of the luminance component (L)—obtaining (50) a modulation value (Ba) from the luminance of said color picture; —obtaining the first component (Y) by multiplying said resulting component by said modulation value (Ba); —obtaining two chrominance components (C1, C2) from said color picture; —obtaining (40) a first factor (r(L(i))) that depends on the value (L(i)) of a pixel (i) of said luminance component (L); —obtaining (30) at least one color component (Ec) from said first component (Y), said two chrominance components (C1, C2) and said first factor (r(L(i))); and—forming the inverse-tone mapped color picture by combining together said at least one color component (Ec).

The present disclosure generally relates to a method and device of encoding a color picture having color components (Ec) comprising obtaining (11) a luminance component (L) and two chrominance components (C1, C2) from the color picture to be encoded. The method for encoding a color picture having color components comprising obtaining at least one chrominance component from the color picture to be encoded, the method further comprises: —determining a first factor based on the value of each pixel (i) of said luminance component; —obtaining at least one final chrominance component by scaling said at least one chrominance component by said first factor; and—encoding (13) said at least one final chrominance component.

A method is disclosed that comprises mapping a high-dynamic range luminance picture to a standard-dynamic range luminance picture based on a backlight value Ba.sub.c associated with the high-dynamic range luminance picture.

A liquid crystal display driving method provided includes the following steps: acquiring a current gray level value of a current frame image; determining a gray level of the current gray level value; if the current gray level value is the high gray level, then determining whether to perform an overvoltage driving according to a first gray level difference threshold value; if the current gray level value is the low gray level, then determining whether to perform the overvoltage driving according to a second gray level difference threshold value. The present invention can precisely determine whether to perform the overvoltage driving on the pixel electrode.

A display device according to example embodiments includes an image analyzer configured to calculate contrast and load of an image of a frame based on R, G, and B image data input corresponding to the frame, an image processor configured to control a peak control coefficient applied to W image data to adaptively control peak luminance based on the contrast and the load, and to respectively generate R′, G′, and B′ image data by subtracting a product of the W image data and the peak control coefficient from each of the R, G, and B image data, a display panel including a plurality of pixels, a data driver configured to generate a data signal based on the R′, G′, B, and W image data, and to provide the data signal to the display panel, and a scan driver configured to provide a scan signal to the display panel.

According to an aspect of the present disclosure, an organic light emitting display device includes a plurality of pixels each including a pixel driving circuit. The plurality of pixels includes an organic light emitting diode and a driving TFT configured to control driving of the organic light emitting diode and including a gate node as a first node, a source node as a second node, and a drain node. Also, the plurality of pixels includes first to third switching TFTs electrically connected to the driving TFT and first and second storage capacitors configured to store a voltage to be applied to the driving TFT DT. Further, the plurality of pixels includes a coupling capacitor connected to a gate node of the third switching TFT so as to increase a voltage to be applied to the gate node of the driving TFT.

A display provides increased contrast and resolution via first LCD panel energized to generate an image and a second LCD panel configured to increase contrast of the image. The second panel is an LCD panel without color filters and is configured to increase contrast by decreasing black levels of dark portions of images using polarization rotation and filtration. The second LCD panel may have higher resolution than the first LCD panel. A half wave plate and/or film is placed in between the first and the second panel. The panels may be directly illuminated or edge lit, and may be globally or locally dimmed lights that may also include individual control of color intensities for each image or frame displayed.