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.

Abstract: Systems and methods for improving displayed image quality of an electronic display including a display pixel and a display driver are provided. A display pipeline receives input image data that indicates target luminance of the display pixel when displaying an image frame on the electronic display; determines a first bit group in pixel response corrected image data by mapping a first bit group in the input image data based at least in part on a first pixel response correction look-up-table; determines a second bit group in the pixel response corrected image data by mapping a second bit group in the input image data based at least in part on a second pixel response correction look-up-table; and outputs the pixel response corrected image data to the display driver to enable the display driver to facilitate displaying the image frame by writing the display pixel based on the pixel response corrected image data.

Abstract: Systems, methods, and devices are provided to reduce a likelihood of image burn-in on an electronic display. Such an electronic device may include image processing circuitry and an electronic display. The image processing circuitry may receive image data and analyze the image data for risk of image burn-in and, based at least in part on the analysis of the image data, reduce a risk of image burn-in at least in part by reducing a local maximum pixel luminance value in at least one of a plurality of regions of the image data over time or by reducing a dynamic range headroom of the image data. The electronic display may display the image data with a reduced risk of image burn-in on the pixels of the electronic display.

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: Devices, storage media, and methods for compensating for aging and temperature variations using dual-loop compensation are provided. The compensating for temperature and aging variations of one or more pixels of the display using a coarse scan loop updated at a faster rate. Compensation also includes compensating for aging variations of the one or more pixels of the display using a fine scan loop updated at a slower rate.

Abstract: An electronic device may be provided with a display. The display may include a backlight having an array of locally dimmable light sources. Control circuitry may provide control signals to the backlight to produce light at different brightness levels. When the brightness level is below a threshold, the control circuitry may use pulse-width-modulation control signals to control the light sources in the backlight. When the brightness level is above the brightness threshold, the control circuitry may use analog control signals to control the light sources in the backlight. The control circuitry may adjust the threshold to achieve different dimming ranges for different brightness settings. A low brightness setting, for example, may have a lower threshold and lower dimming range than a high brightness setting, which may help produce darker darks when the display operates in a low brightness setting.

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: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The image frames may be displayed with positive and negative polarities to help reduce charge accumulation effects. A charge accumulation tracker may analyze the image frames to determine when there is a risk of excess charge accumulation. The charge accumulation tracker may analyze information on gray levels, frame duration, and frame polarity. The charge accumulation tracker may compute a charge accumulation metric for entire image frames or may process subregions of each frame separately. When subregions are processed separately, each subregion may be individually monitored for a risk of excess charge accumulation.

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: 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: An electronic device may be provided with a display. A content generator may generate frames of image data to be displayed on the display. Control circuitry in the electronic device may be used in implementing a tone mapping engine. The tone mapping engine may display content from the content generator on the display in accordance with a content-luminance-to-display luminance mapping. The content-luminance-to-display-luminance mapping is characterized by tone mapping parameters such as a black level, a reference white level, and a specular white level. The tone mapping engine may adjust the tone mapping parameters based on ambient light levels, user brightness settings, content statistics, and display characteristics.

Abstract: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The image frames may be displayed with positive and negative polarities to help reduce charge accumulation effects. A charge accumulation tracker may analyze the image frames to determine when there is a risk of excess charge accumulation. The charge accumulation tracker may analyze information on gray levels, frame duration, and frame polarity. The charge accumulation tracker may compute a charge accumulation metric for entire image frames or may process subregions of each frame separately. When subregions are processed separately, each subregion may be individually monitored for a risk of excess charge accumulation.

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: Systems and methods for improving perceived image quality of an electronic display, which includes a co-located sub-pixel that controls luminance of a first color component and an offset sub-pixel that controls luminance of a second color component. A display pipeline communicatively coupled to the electronic display determines image data, which indicates target luminance of the first, the second, and a third color component at an image pixel; determines edge parameters, which indicate whether an edge is expected to be present at the offset sub-pixel, based on a difference metric between a first image pixel block around the offset sub-pixel and a second image pixel block offset from the first image pixel block; and determines offset sub-pixel image data by filtering an image pixel group around the offset sub-pixel based at least in part on the edge parameters, wherein the offset sub-pixel image data indicates target luminance of the offset sub-pixel.

Abstract: Systems, methods, and computer readable media to improve the operation of display systems are disclosed. In general, techniques are disclosed for dynamically adjusting backlight elements based on image content. More particularly, a backlight element's intensity may be targeted for boosting (i.e., increasing) based on content of the backlight element's corresponding image region, where after a check may be made to determine if the proposed increase is likely to risk generation of a halo. If the proposed intensity increase would risk a halo, the backlight element's proposed intensity may be dimmed. Repeating the boost/dim cycle in an iterative fashion permits an image to be displayed with brighter highlights and deeper blacks.

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 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 and methods are provided to perform refresh-rate dependent dithering. One embodiment describes a computing device that includes an image source that generates spatially dithered image data and an electronic display communicatively coupled to the image source. More specifically, the electronic display receives the spatially dithered image data from the image source and determines a refresh rate with which to display an image by comparing a local histogram and an artifact histogram, in which the local histogram describes pixel grayscale distribution of a portion of the image and the artifact histogram describes a pixel grayscale distribution that when displayed will cause a perceivable artifact. Additionally, when the determined refresh rate is less than a threshold refresh rate of the electronic device, the electronic display spatially dithers the image data without temporally dithering the image data and displays the image based at least in part on the spatially dithered image data.

Abstract: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The image frames may be displayed with positive and negative polarities to help reduce charge accumulation effects. A charge accumulation tracker may analyze the image frames to determine when there is a risk of excess charge accumulation. The charge accumulation tracker may analyze information on gray levels, frame duration, and frame polarity. The charge accumulation tracker may compute a charge accumulation metric for entire image frames or may process subregions of each frame separately. When subregions are processed separately, each subregion may be individually monitored for a risk of excess charge accumulation.

Abstract: System and method for improving displayed image quality of an electronic display that displays a first image frame by applying a first voltage to a display pixel and a second image frame directly before the first image frame by applying a second voltage to the display pixel. A display pipeline is communicatively coupled to the electronic display and receives first image data corresponding with the first image frame, where the image data includes a first grayscale value corresponding with the display pixel. Additionally the display pipeline determines an inversion balancing grayscale offset based at least in part on the first grayscale value when polarity of the first voltage and polarity of the second voltage are the same and determines magnitude of the first voltage by applying the inversion balancing grayscale offset to the first grayscale value to reduce likelihood of a perceivable luminance spike when displaying the first image frame.