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 include a display having an array of display pixels. Storage and processing circuitry may generate display data for the display in an RGB input color space. The display may display the display data in an RGBW output color space. Display control circuitry may use sets of predetermined conversion factors to convert display data from the RGB input color space to the RGBW output color space without requiring conversion to a device-independent color space. Each set of predetermined conversion factors may be associated with a color in a set of predetermined colors. Using the sets of predetermined conversion factors, the display control circuitry may convert RGB values in the input color space to RGBW values in the output color space. The display control circuitry may supply data signals corresponding to the display data in the RGBW output color space to the array of display pixels.
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:
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.
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 light emitting diode (LED) display can calculate a common voltage charge of a line of pixels in the LED display, the common voltage charge comprising a difference between a first line of pixels and a second line of pixels. If the calculated common voltage charge exceeds a predetermined threshold, a toggle matrix can be generated for the line of pixels. The toggle matrix can include a matrix of charge values generated by calculating a difference in charge values for each subpixel a first line of subpixels with each subpixel a second line of subpixels. The LED display can identify one or more regions of subpixels exhibiting the predetermined toggle pattern in the toggle matrix. The LED display can generate a voltage correction charge to apply to affected regions of the display. Alternatively, the subpixels or pixels could be swapped with adjacent pixels to reduce toggling or settling error.
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 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:
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:
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.