G09G3/2055

Parallel implementation of a dithering algorithm for high data rate display devices
10909903 · 2021-02-02 · ·

A display device includes a display controller that performs a high-throughput dithering operation. The display controller performs a quantization operation with pixel values generated by a graphics processor to generate quantized pixel values and residual error values. The display controller distributes the residual error values associated with a first group of quantized pixel values to a second group of quantized pixel values based on a set of distribution weights. A given distribution weight defines what fraction of a given residual error value is distributed to a given quantized pixel value included in the second group of quantized pixel values. The distribution weights are calibrated to permit the display controller to compute different fractions of residual error values using bit shifting logic instead of complex combinatorial logic.

Systems and methods for mask-based temporal dithering
11056040 · 2021-07-06 · ·

In one embodiment, a computing system may determine that a target grayscale value for a frame falls within a predetermined grayscale range. The system may compute, based on the target grayscale value, barycentric weights for a predetermined barycentric coordinate system associated with vertices that each represents a subframe combination of zero or more subframe identifiers. The system select, using the barycentric weights and threshold values associated with respective dots in a dithering mask, a set of non-overlapping dot patterns from the dithering mask corresponding to the vertices of the barycentric coordinate system. The dots in the dithering mask may satisfy a spatial stacking constraint. The system may generate subframes to represent the frame based on the set of non-overlapping dot patterns and the subframe combination represented by each of the vertices.

SYSTEMS AND METHODS FOR SPATIO-TEMPORAL DITHERING
20210027694 · 2021-01-28 ·

In one embodiment, the system may receive a target pixel value for a pixel of an image of a series of images. The system may determine an error-modified target pixel value based on the target pixel value and a first error value. The system may generate a quantized pixel value corresponding to the error-modified target pixel value for display by the pixel of the image. The system may determine an aggregated representation of quantized pixel values displayed by the pixel of the image and corresponding pixels of one or more preceding images of the series of images. The system may determine a second error value based on the aggregated representation of the quantized pixel values and the first error-modified target pixel value. The system may dither at least a portion of the second error value to at least a corresponding pixel of a next image in the series of images.

SYSTEMS AND METHODS FOR MASK-BASED SPATIO-TEMPORAL DITHERING
20210027725 · 2021-01-28 ·

In one embodiment, a computing system may receive a target image with a first number of bits per color. The system may access masks that each includes dots associated with a grayscale range. A subset of the dots associated with each of the masks may be associated with a subrange of the grayscale range. The dots within the subsets of dots associated with the masks may have different positions. The system may generate a number of images based on the target image and the masks. Each of the images may have a second number of bits per color smaller than the first number of bits per color. The system may display the images sequentially on a display for representing the target image.

Image signal processing device, dither pattern generating method and dither pattern generating program
10847078 · 2020-11-24 · ·

A storage device stores dither patterns composed of a three-dimensional block consisting of the number H of dots in a horizontal directionthe number V of lines in a vertical directionthe number F in a frame direction. Each value from a minimum value to a maximum value of dither values of n bits is written in each address of the storage device. When each value is written into the storage device, processing of obtaining a spatiotemporal density value indicating a degree of density of an address in which a dither value has already been written in a three-dimensional predetermined area centered on each of the addresses in which a new dither value is writable, and processing of selecting an address having the smallest spatiotemporal density value among the addresses in which a new dither value is writable and writing a dither value are repeated.

Video display device capable of compensating for display defects
10810918 · 2020-10-20 · ·

A video display device capable of compensating for display defects, comprising: liquid crystal panel for displaying an image through a pixel matrix; a data driver for outputting data to data lines of the liquid crystal display panel; a gate driver for driving the gate lines of the liquid crystal display panel; a timing controller for receiving compensated data, uncompensated data and synchronizing signals to output a gate control signal to the gate driver and to output both resultant data and a data control signal to the data driver; and a memory for storing information on point defect information on the liquid crystal display panel, and at least one of horizontal and vertical line defects of the liquid crystal display panel of the liquid crystal display panel; and a data compensation circuit for receiving display data and synchronizing signals, and outputting compensated data to the timing controller based on the information in the memory and uncompensated data to the timing controller, wherein the data compensation circuit includes a vertical line compensator for compensating a vertical line defect of the liquid crystal display panel, a horizontal line compensator for compensating a horizontal line defect of the liquid crystal display panel, and a multiplexer for selecting an output from one of the vertical line compensator and the horizontal line compensator in accordance with whether a defect is a vertical line defect or a horizontal line defect.

DISPLAY DEVICE PERFORMING STILL IMAGE DETECTION, AND METHOD OF OPERATING THE DISPLAY DEVICE
20200327846 · 2020-10-15 ·

A display device including a display panel including a plurality of pixels, and a driver configured to drive the display panel. The driver includes a dither configured to perform a dithering operation on image data including a plurality of pixel data for the plurality of pixels to generate dithered image data including a plurality of dithered pixel data respectively corresponding to the plurality of pixel data, and a still image detector configured to receive the dithered image data, to detect dither-irrelevant pixel data that are not changed from the plurality of pixel data by the dithering operation among the plurality of dithered pixel data, and to determine whether the dithered image data represent a still image by using the dither-irrelevant pixel data.

Methods and apparatuses for driving display systems
10796623 · 2020-10-06 · ·

Methods and apparatus for image processing are provided. A method for image processing includes: (a) accessing, in a lookup table, a current pattern index for a current pixel based on a current pixel input value and a previous pattern index; (b) accessing, in a dither mask array, a threshold value for the current pixel based on a location of the current pixel; (c) comparing the current pattern index with the threshold value; (d) determining a current pixel output value for activation of the current pixel based on a result of the comparing; (e) storing the current pattern index to serve as the previous pattern index for a next image; and (f) repeating acts (a)-(e) for each pixel in the image.

DISPLAY APPARATUS AND DRIVING METHOD OF DISPLAY APPARATUS
20200279520 · 2020-09-03 ·

[Object] To enable an image to be displayed in a more suitable manner, in a case where color sequential drive is adopted. [Solution] A display apparatus includes: an addition section that adds a dither signal to a digital image signal for each of a plurality of color components, the digital image signal being generated on a basis of each of the plurality of color components different from each other, and inputted in predetermined order for each sub-frame included in a frame; a conversion section that performs digital to analog conversion of converting the digital image signal to which the dither signal is added into an analog image signal; and a control section that controls a pattern of the dither signal, at each predetermined cycle including a plurality of the sub-frames, depending on the order in which the digital image signal for each of the color components is inputted, within the frame.

Pre-compensation for pre-toggling-induced artifacts in electronic displays

Systems and methods reduce likelihood of hysteresis that reduces perceived image quality of a subsequent image frame by toggling the display pixels to relax the display pixels by overwriting previous image frame data. During non-emission periods of the pixels, the pixels may be pre-toggled or exercised to improve response time and accuracy of the pixel. Data for pixels being programmed may also be used to pre-toggle other pixels reducing overhead but increasing cross-talk. Since the amount of cross-talk is related to content of the pixels being pre-toggled, a line buffer may be used to store image data for the pixels being pre-toggled. This stored image data may be used to determine how much pre-compensation is to be applied to data for the pixels being programmed. In other words, an amount of compensation applied is based at least in part on the content (e.g., greyscale levels) of the image data.