IR drop compensation for large OLED display panels
Variation in IR drop across the electronic display may result in display pixels that are intended to be programmed with the same image data to behave differently, resulting in visible image artifacts. The current drawn by the intensity of the display pixels displaying an aggressor image may cause a voltage (IR) drop across a non-aggressing (or victim) portion of the display. This IR drop across the electronic display may result in a visible image artifact, such as a transition band across the non-aggressing portion of the electronic display. To reduce or eliminate image artifacts, IR drop compensation may be provided to the electronic display. The IR drop compensation may be determined on a per-zone basis based on present frame average pixel luminance (APL), previous frame APL, and IR drop due to each respective zone in a plurality of zones across the electronic display.
1 . An electronic device, comprising:
an electronic display comprising a plurality of pixels configured to emit light based on processed image data; and
processing circuitry configured to:
receive input image data;
determine average pixel luminance (APL) for each zone of a plurality of zones based on a difference between a first APL associated with a present frame of the input image data and between a second APL associated with a subsequent frame of the input image data;
generate a plurality of current-resistance voltage (IR) drop grid maps for each zone of the plurality of zones, wherein each IR drop grid map is based on the APL for a particular zone of the plurality of zones and an estimated IR drop across each other zone of the plurality of zones due to the APL for that particular zone;
determine, based on accumulating each of the IR drop grid maps, IR drop across the electronic display;
determine an IR drop compensation based on the IR drop across the electronic display; and
generate, based on applying the IR drop compensation to the input image data, the processed image data.
2 . The electronic device of claim 1 , wherein the processing circuitry is configured to determine the APL for each zone of the plurality of zones by determining APL for each subline of a plurality of sublines in each respective zone of the plurality of zones.
3 . The electronic device of claim 2 , wherein the processing circuitry is configured to determine a delta subline APL value for each subline within each zone of the plurality of zones, wherein each delta subline APL value is determined based on a differential between a first subline APL value corresponding to the present frame of the input image data and a second subline APL value corresponding to the subsequent frame of the input image data.
4 . The electronic device of claim 3 , wherein the processing circuitry is configured to determine the APL for each zone by accumulating each delta subline APL value in a respective zone to generate a delta zone APL.
5 . The electronic device of claim 4 , wherein the processing circuitry is configured to generate the plurality of IR drop grid maps based on the delta zone APL for each zone of the plurality of zones.
6 . The electronic device of claim 4 , wherein the processing circuitry is configured to sum the plurality of IR drop grid maps to determine a panel-level IR drop across the electronic display.
7 . The electronic device of claim 1 , wherein the processing circuitry is configured to convert the input image data to a pixel voltage, determine the IR drop compensation as a pixel voltage compensation, and sum the pixel voltage and the pixel voltage compensation.
8 . The electronic device of claim 7 , wherein the processing circuitry is configured to convert the sum of the pixel voltage and the pixel voltage compensation to a sum of the input image data and a compensation gray level via a voltage-to-gray level conversion.
9 . The electronic device of claim 8 , wherein the processing circuitry is configured to output the pixel voltage compensation by subtracting the input image data from the sum of the input image data and the compensation gray level.
10 . The electronic device of claim 1 , wherein the plurality of zones comprise rectangular, non-uniform, and non-overlapping zones.
11 . The electronic device of claim 1 , wherein each zone of the plurality of zones is based on a number of calibration points disposed at each corner of each respective zone.
12 . Tangible, non-transitory, computer-readable media, comprising computer-executable instructions that, when executed, cause one or more processors to:
determine, based on first image frame data associated with a present frame displayed on an electronic display, a first average pixel luminance (APL) value for a subline of display pixels in a zone of the electronic display;
determine, based on second image frame data associated with a subsequent frame to be displayed on the electronic display, a second APL value for the subline of display pixels in the zone of the electronic display;
generate, based on a delta between the first APL value and the second APL value, a first delta subline APL value;
determine, based on the first image frame data associated with the present frame, a third APL value for an additional subline of display pixels in the zone of the electronic display;
determine, based on the second image frame data associated with the subsequent frame, a fourth APL value for the additional subline of display pixels in the zone of the electronic display based on the second image frame data associated with the subsequent frame;
generate, based on an additional delta between the third APL value and the fourth APL value, a second delta subline APL value;
accumulate the first delta subline APL value and the second delta subline APL value to generate a delta zone APL value; and
determine, based on the delta zone APL value, a current-resistance (IR) drop associated with the zone.
13 . The tangible, non-transitory, computer-readable media of claim 12 , comprising the computer-executable instructions that, when executed, cause the one or more processors to:
generate an IR drop grid map based on an IR drop across the electronic display due to the IR drop associated with the zone.
14 . The tangible, non-transitory, computer-readable media of claim 12 , comprising the computer-executable instructions that, when executed, cause the one or more processors to:
determine an additional IR drop associated with an additional zone based on an additional delta zone APL value and a plurality of delta subline APL values associated with the additional zone.
15 . The tangible, non-transitory, computer-readable media of claim 14 , comprising the computer-executable instructions that, when executed, cause the one or more processors to:
generate an additional IR drop grid map based on the additional IR drop across the electronic display due to the additional IR drop associated with the additional zone.
16 . The tangible, non-transitory, computer-readable media of claim 15 , comprising the computer-executable instructions that, when executed, cause the one or more processors to:
accumulate the IR drop grid map and the additional IR drop grid map to determine a per-panel IR drop across the electronic display.
17 . An electronic device, comprising:
an electronic display comprising a plurality of pixels configured to emit light based on processed image data; and
processing circuitry configured to:
receive input image data;
generate a plurality of current-resistance voltage (IR) drop grid maps based on the input image data, each IR drop grid map corresponding to an IR drop of a particular zone of a plurality of zones and an estimated IR drop impact of the particular zone across the plurality of zones based on a delta average pixel luminance (APL) value for the particular zone, the delta APL value for particular zone comprising a difference between a first APL for the particular zone associated with a first frame of the input image data and between a second APL associated for the particular zone associated with a second frame of the input image data;
determine IR drop across the electronic display based on the plurality of IR drop grid maps;
determine an IR drop compensation based on the IR drop across the electronic display; and
generate, based on applying the IR drop compensation to the input image data, the processed image data.
18 . The electronic device of claim 17 , wherein the processing circuitry is configured to determine the IR drop across the electronic display by accumulating the plurality of IR drop grid maps.
19 . The electronic device of claim 17 , comprising memory configured to store a value of the second APL, wherein the processing circuitry is configured to determine, based on the value of the second APL, an additional delta APL value for an additional frame of additional input image data.
20 . The electronic device of claim 17 , wherein the processing circuitry is configured to identify, based on a plurality of calibration points corresponding to intersections between one or more rows of pixels and one or more columns of pixels on the electronic display, the plurality of zones.