Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated by a backlight unit that includes an array of light-emitting diodes. A backlight brightness selection circuit may select brightness values for the light-emitting diodes. The backlight brightness selection circuit may select the brightness values based on image data, based on brightness values used in previous image frames, based on device information, and/or based on sensor information. The backlight brightness selection circuit may select the backlight brightness levels to mitigate visible artifacts such as flickering and halo. The backlight levels selected by the backlight brightness selection may be modified by a power consumption compensation circuit. The power consumption compensation circuit may estimate the amount of power consumption required to operate the backlight using the target brightness levels and may modify the target brightness levels to meet maximum power consumption requirements.

Abstract: Source content super-sampled to a first resolution in an extended range space is obtained. A representation of a subpixel geometry of a display panel displaying the source content is obtained. The display panel includes, for every pixel, plural subpixel elements for three or more color primaries. A native resolution of the display panel is lower than the first resolution of the source content. An optimization operation is performed based on a set mode of the display panel and the representation of the subpixel geometry to derive a global optimization for determining, for a given pixel value based on the source content, an energy distribution between the plurality of subpixel elements of a corresponding pixel of the display panel. The source content in the extended range space is converted into intermediate content in a display space based on the global optimization. The intermediate content is further optimized based on error minimization.

Abstract: A display may have an active area that includes display pixels. The display may include an inactive notch region that extends into the active area. Data lines may provide image data from display driver circuitry to the display pixels. The image data may include data signals that correspond to portions of the display that do not include pixels, such as the inactive notch region. The null data signals may cause nonuniformities in the displayed image. The null data signals may be adjusted to minimize the nonuniformities. Null data signals corresponding to the inactive notch region may be adjusted to have gray levels that gradually decrease with distance from the border between the inactive notch and the active area. All of the data signals corresponding to the inactive notch may be set to a uniform gray level.

Abstract: The disclosure describes procedures for dynamically employing a variable refresh rate at an LCD display of a consumer electronic device, such as a laptop computer, a tablet computer, a mobile phone, or a music player device. In some configurations, the consumer electronic device can include a host system portion, having one or more processors and a display system portion, having a timing controller, a buffer circuit, a display driver, and a display panel. The display system can receive image data and image control data from a GPU of the host system, evaluate the received image control data to determine a reduced refresh rate (RRR) for employing at the display panel, and then transition to the RRR, whenever practicable, to conserve power. In some scenarios, the transition to the RRR can be a transition from a LRR of 50 hertz or above to a RRR of 40 hertz or below.

Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated by a backlight unit that includes an array of light-emitting diodes. A backlight brightness selection circuit may select brightness values for the light-emitting diodes. The backlight brightness selection circuit may select the brightness values based on image data, based on brightness values used in previous image frames, based on device information, and/or based on sensor information. The backlight brightness selection circuit may select the backlight brightness levels to mitigate visible artifacts such as flickering and halo. The backlight levels selected by the backlight brightness selection may be modified by a power consumption compensation circuit. The power consumption compensation circuit may estimate the amount of power consumption required to operate the backlight using the target brightness levels and may modify the target brightness levels to meet maximum power consumption requirements.

Abstract: Systems and methods are provided for improving displayed image quality of an electronic display that includes a display pixel. The electronic display displays a first image frame directly after a second image frame by applying an analog electrical signal to the display pixel. To facilitate display of the first image frame, circuitry receives image data corresponding to the image frame, in which the image data includes a grayscale value that indicates target luminance of the display pixel; determines expected refresh rate of the first image frame based at least in part on actual refresh rate of the second image frame; determines a pixel response correction offset based at least in part on the expected refresh rate of the first image frame; and determines processed image data by applying the pixel response correction offset to the grayscale value, in which the processed image data indicates magnitude of the analog electrical signal.

Abstract: A method for controlling a parking mode for a vehicle includes detecting an activation action of a user of the vehicle, determining a movement status of the vehicle, and activating a parking mode for the vehicle by closing a parking brake of a brake device of the vehicle and by engaging a gearshift lock of a transmission of the vehicle.

Abstract: Systems, methods, and computer readable media to improve the operation of display systems are described herein. In general, techniques are disclosed for ambient and content adaptive local tone mapping operations that improve display readability under bright ambient light conditions. More particularly, techniques disclosed herein improve contrast and brightness of dark image content while preserving bright areas. The disclosed architecture and operational methodologies generate high contrast images (e.g., amplifying dark regions while preserving bright content), preserve uniform backgrounds (e.g., static background pixels), are stabile in the face of local and global histogram changes (e.g., background not affected by small moving objects such as a mouse pointer), and provide near seamless fade-in and fad-out transitions.

Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated by a backlight unit that includes an array of light-emitting diodes. A backlight brightness selection circuit may select brightness values for the light-emitting diodes. The backlight brightness selection circuit may select the brightness values based on image data, based on brightness values used in previous image frames, based on device information, and/or based on sensor information. The backlight brightness selection circuit may select the backlight brightness levels to mitigate visible artifacts such as flickering and halo. The backlight levels selected by the backlight brightness selection may be modified by a power consumption compensation circuit. The power consumption compensation circuit may estimate the amount of power consumption required to operate the backlight using the target brightness levels and may modify the target brightness levels to meet maximum power consumption requirements.

Abstract: Devices and methods for reducing or eliminating spatiotemporal dithering image artifacts are provided. By way of example, a method includes providing positive polarity and negative polarity data signals to a plurality of pixels of a display during a first frame period, in which the first frame period corresponds a first spatiotemporal rotation phase. The method includes providing the positive polarity signals and the negative polarity signals to the plurality of pixels of the display during a second frame period, in which the second frame period corresponds a second spatiotemporal rotation phase. A spatiotemporal rotation phase sequence provided to the display comprises the first spatiotemporal rotation phase and the second spatiotemporal rotation phase. One of the first spatiotemporal rotation phase and the second spatiotemporal rotation phase of the spatiotemporal rotation phase sequence is altered during the first frame period or the second time period.

Abstract: An electronic device has a display with a pixel array overlapping an array of temperature sensors. Control circuitry in the device may gather temperature measurements from the temperature sensor array. The control circuitry may apply a global offset to the temperature measurements and may apply a damping factor to the globally offset measurements to produce a two-dimensional temperature profile for the display. A look-up table or other data structure may be used to store information on pixel color correction gain values as a function of temperature. This temperature-gain information and temperature information from the two-dimensional temperature profile may be used by display circuitry in the device to display color-corrected images on the display.

Abstract: Aspects of the subject technology relate to display circuitry including pixel overdrive circuitry. The pixel overdrive circuitry includes a compression engine that compresses a previous display frame, for storage and comparison to a current display frame without compression or decompression of the current display frame. The compression engine compresses the previous frame in such a way that the maximum compression error is always known and can be used to determine whether to perform overdrive operations for the current frame without compressing and decompressing the current display frame. The compression engine selects gradient encoding or decimation encoding for the compression of the previous display frame and can perform successive decimation operations within the gradient encoding operations to help reduce the size of the compressed previous frame while maintaining the quality of the ultimate overdriven current frame.

Abstract: 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.

Abstract: Aspects of the subject technology relate to electronic devices with displays and ambient light sensors. An electronic device modifies the color of images to be displayed based on measured ambient light color. The modification is performed in a perceptually uniform color space and includes a determination of a bleaching effect of reflected ambient light, and a determination of a color correction factor to be applied within the perceptually uniform color space,7 based on the determined bleaching effect. The modification may also include an application of a strength factor that mitigates out-of-gamut colors in color compensated images.

Abstract: Devices and methods for error diffusion and spatiotemporal dithering are provided. By way of example, a method of operating a display includes receiving a pixel input, a set of pixel coordinates, and a current frame number. A kernel and a particular kernel bit of the kernel is selected from a set of kernels, based upon the pixel input, the pixel coordinates, the frame number, or any combination thereof. A dithered output is determined based at least in part upon the kernel bit. When the display is in a diamond pixel configuration, the dithered output is applied in accordance with a diamond pattern formed by red, blue, or red and blue pixel channels.

Abstract: An electronic device may be provided with a display. Standard and high dynamic range content may be produced by content generators operating on control circuitry. In a first mode of operation, standard dynamic range content is displayed. In a second mode of operation, high dynamic range content is displayed. In a third mode of operation, standard dynamic range content and high dynamic range content are simultaneously displayed. Tone mapping parameters may be produced by a tone mapping engine for use in displaying the standard and high dynamic range content. The tone mapping parameters may be selected based on factors such as ambient light level, user brightness setting, content statistics, and display characteristics. Tone mapping parameters may be selected to accommodate simultaneous display of standard and high dynamic range content and to accommodate transitions between standard and high dynamic range content.

Abstract: Access in a knowledge graph, comprising nodes and edges connecting two or more nodes, is controlled by assigning each node to a non-intersecting zone. A first and second zone identifier, each indicative of a zone occupied by a node where an edge ends, are each stored. Determining an access graph comprising an access node for each zone, access edges representing edges between the zones, and a first list of the zones. Each entry in the first list relates to a zone and a second list of node identifiers, each indicative of a node occupying the zone. A first and second access control list, each related to a zone where an access edge ends and to which a access node in the access graph relates, are stored in each access edge.

Abstract: A display device may include a processor that may receive image data, such that the image data may include gray level data and display brightness value (DBV) data for a first pixel of a display. The processor may then determine a gain compensation factor associated with the first pixel based on a correction spatial map, a brightness adaptation lookup table (LUT), the gray level data, and the DBV data. The processor may then determine an offset compensation factor associated with the first pixel based on the correction spatial map, the brightness adaptation lookup table (LUT), the gray level data, and the DBV data. The processor may generate compensated gray level data by applying the gain compensation factor and the offset compensation factor to the gray level data and transmit the compensated gray level data to pixel driving circuitry associated with the first pixel.

Abstract: This application relates to performing certain dithering processes to eliminate display artifacts such as flicker, which can be caused by charge accumulation at the display. The dither process can be performed by a display controller that uses a group lookup method for identifying groups of dithering patterns that can be combined to expand a number of color values available to the display. The dither process can also be performed as a temporal process that incorporates groups of dithering patterns into frames and shifts a spatial arrangement of the groups of dithering patterns over a sequence of frames. Additionally, the dither process can incorporate counters that count the number of times a particular spatial arrangement of dithering patterns has been used in a sequence of frames in order that each spatial arrangement of dithering patterns will share an average count with other spatial arrangements over a sequence of frames.

Abstract: This application relates to systems, methods, and apparatus for compensating voltage for pixels of a display panel based on the location of the pixels within the display panel. An amount of voltage compensation is assigned to each pixel or a group of pixels within the display panel in accordance with a calibration of the display panel. During operation of the display panel, pixel data is generated for a location of the display panel, and the pixel data is modified according to the amount of voltage compensation corresponding to the location. By modifying the pixel data in this way, spatial variations in voltage across the display panel can be mitigated in order to reduce the occurrence of certain display artifacts at the display panel.