TWI766795B - Adaptive current limiting method for self-luminous display, driving circuit and self-luminous display - Google Patents

Abstract

An adaptive current limiting method for a self-luminous display, comprising: performing a color gamut conversion on RGB data of a previous frame to obtain a pixel brightness distribution in a color space; counting the pixel brightness distribution to obtain a high-brightness pixel group; A low-brightness pixel group, and a weighted average calculation is performed on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a second average value, and the first average value and the second average value are obtained. performing a subtraction operation on the average value to obtain a difference value; determining a luminance lookup table according to the difference value and mapping an input pixel luminance according to the luminance lookup table to generate an output pixel luminance; and the output pixel luminance and an input pixel color The inverse of the gamut conversion is performed to produce an (R,G,B) output data.

Description

Adaptive current limiting method for self-luminous display, driving circuit and self-luminous display

The present invention relates to a self-luminous display, in particular to an adaptive current limiting method for the self-luminous display.

General self-luminous displays, such as OLED or LED displays, reduce the driving current when the display image meets certain conditions (eg, the display image is a high-brightness static image) in order to reduce power consumption and prolong the life of its light-emitting elements.

A possible way to reduce the overall operating current is ACL (automatic current limiter; automatic current limiter), which determines the brightness reduction degree of the current frame image based on the average pixel brightness of a previous frame.

However, when the monitor displays a static image, if the pixel data of half of the static image is high brightness (for example, the brightness value is 255), and the pixel data of the other half of the image is low brightness (for example, the brightness value is 0) At this time, the average pixel brightness is about 127. At this time, the general ACL will think that the picture is medium brightness and will not reduce the brightness. If it is lowered, the visual content of the static image will basically remain unchanged, the power consumption of the display can be further reduced, and the lifespan of the light-emitting elements of the display can be further extended.

In order to solve the above-mentioned problems, there is an urgent need in the art for a novel current limiting method for a self-luminous display.

One objective of the present invention is to disclose an adaptive current limiting method for a self-luminous display, which can determine the brightness adjustment of each pixel in a high-brightness range according to the difference in brightness average between high-brightness groups and low-brightness groups of a frame of display data. The reduction distribution can further reduce the power consumption of a self-luminous display without affecting the chroma content of the picture, and thereby prolong its service life.

Another object of the present invention is to disclose an adaptive current limiting method for a self-luminous display, which can dynamically update the luminance dimming amount distribution to instantly provide corresponding high-brightness pixels for different picture data with different luminance average differences Press down processing, thereby adaptively reducing power consumption and extending the life of self-illuminating displays.

To achieve the aforementioned purpose, an adaptive current limiting method for a self-luminous display is proposed, which includes:

Perform a color gamut conversion on the RGB data of the previous frame to obtain a pixel brightness distribution in a color space;

Counting the pixel brightness distribution to obtain a high-brightness pixel group and a low-brightness pixel group, and performing a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group respectively to obtain a first average and a second average value, and perform a subtraction operation on the first average value and the second average value to obtain a difference;

determining a luminance lookup table according to the difference and mapping an input pixel luminance according to the luminance lookup table to generate an output pixel luminance; and

The inverse conversion of the color gamut conversion is performed on the output pixel luminance and an input pixel chroma to generate an (R,G,B) output data.

In one embodiment, the color space represents each pixel with a luminance data and a chrominance data.

In one embodiment, the color space may be a YUV space or a YCbCr space.

In one embodiment, the high-brightness pixel group and the low-brightness pixel group use a medium brightness value as a dividing point, that is, pixels greater than or equal to the medium brightness value are classified into the high-brightness pixel group, and less than The pixels of the medium luminance value are classified into the low luminance pixel group.

In one embodiment, the luminance lookup table is used to map an input luminance to an output luminance, wherein when the input luminance is not higher than a threshold, the output luminance is equal to the input luminance; and in all When the input brightness is higher than the threshold, the output brightness is equal to the input brightness minus a reduction amount, and the reduction amount is proportional to the input brightness and the difference.

In one embodiment, the (R, G, B) output data of each pen is used to generate a corresponding current to drive a self-luminous display panel, and the self-luminous display panel can be a micro-LED display. panel, mini light emitting diode display panel, quantum dot light emitting diode display panel or organic light emitting diode display panel.

In order to achieve the aforementioned object, the present invention further provides a driving circuit, which includes a color gamut conversion unit, a brightness distribution analysis unit, a look-up table generation unit, a brightness adjustment unit and a color gamut inverse conversion unit to perform a self-luminous display panel. A current limiting program, the current limiting program includes:

The color gamut conversion unit receives RGB data from an RGB input stream, and performs a color gamut conversion on the RGB data to obtain a pixel brightness and a pixel chroma in a color space;

The brightness distribution analysis unit performs the following operations: receiving a frame of the pixel brightness and performing a brightness distribution analysis on it to obtain a pixel brightness distribution N(Y) representing the picture data of the previous frame, where Y represents the pixel Brightness, N represents the number of pixels; and count the pixel brightness distribution N(Y) to obtain a high-brightness pixel group and a low-brightness pixel group, and perform a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group respectively obtaining a first average value and a second average value, and performing a subtraction operation on the first average value and the second average value to obtain a difference;

The lookup table generating unit determines a luminance lookup table according to the difference, wherein the luminance lookup table is used to map a pixel luminance to an output luminance, wherein when the pixel luminance is not higher than a threshold, The output brightness is equal to the pixel brightness; and when the pixel brightness is higher than the threshold, the output brightness is equal to the pixel brightness minus a tune-down amount that is proportional to the pixel brightness. proportional to and proportional to the difference;

The brightness adjustment unit maps the current pixel brightness according to the brightness lookup table to generate the output brightness; and

The color gamut inverse conversion unit performs the inverse conversion operation of the color gamut conversion on the output luminance and the current pixel chroma to generate an (R, G, B) output data, thereby generating an RGB output stream.

In one embodiment, the color space may be a YUV space or a YCbCr space.

In one embodiment, the high-brightness pixel group and the low-brightness pixel group use a medium brightness value as a dividing point, that is, pixels greater than or equal to the medium brightness value are classified into the high-brightness pixel group, and less than The pixels of the medium luminance value are classified into the low luminance pixel group.

In one embodiment, the (R, G, B) output data of each pen is used to generate a corresponding current to drive the self-luminous display panel, and the self-luminous display panel can be a micro-LED display. panel, mini light emitting diode display panel, quantum dot light emitting diode display panel or organic light emitting diode display panel.

In order to achieve the aforementioned objective, the present invention further provides a self-luminous display, which has the aforementioned driving circuit and the self-luminous display panel.

In order to enable your examiners to further understand the structure, features and purposes of the present invention, the accompanying drawings and detailed descriptions of preferred specific embodiments are as follows.

The principle of the present invention is:

(1) Counting a pixel brightness distribution in a color space of the previous frame of RGB data to obtain a high-brightness pixel group and a low-brightness pixel group;

(2) according to the difference between the average values of the high-brightness pixel group and the low-brightness pixel group, determine the distribution of the brightness reduction amount of each pixel in a high-brightness range; and

(3) Decrease the pixel luminance value of a current frame of RGB data within the high luminance range in the color space according to the luminance decrease amount distribution, and then convert the color space back to the RGB space to generate a frame of RGB output data , so that a self-luminous display can further reduce power consumption when displaying a picture with two high-brightness difference regions, and thus prolong its service life.

Please refer to FIG. 1 , which shows a flow chart of an embodiment of an adaptive current limiting method for a self-luminous display of the present invention. As shown in FIG. 1 , the adaptive current limiting method of the self-luminous display includes: performing a color gamut conversion on the RGB data of the previous frame to obtain a pixel brightness distribution in a color space (step a); counting the pixel brightness distribution obtaining a high-brightness pixel group and a low-brightness pixel group, and performing a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a second average value, and the A subtraction operation is performed between the first average value and the second average value to obtain a difference value (step b); a luminance lookup table is determined according to the difference value and an input pixel luminance is mapped according to the luminance lookup table to generate an output pixel luminance (step c); and perform inverse conversion of the color gamut conversion on the output pixel luminance and an input pixel chroma to generate an (R, G, B) output data (step d).

In step a, the color space may be a color space representing each pixel with a luminance data and a chroma data, for example, the color space may be a YUV space or a YCbCr space, wherein Y represents the luminance, (U, V) and (Cb, Cr) are combined to represent chroma.

In step b, the high-brightness pixel group and the low-brightness pixel group use a medium brightness value (for example, 128) as a dividing point, that is, pixels greater than or equal to the medium brightness value are classified as the high-brightness pixel group, and pixels with values less than the mid-intensity value are classified into the low-intensity pixel group. For example, if the pixel brightness distribution has N brightness values ranging from 0 to 127, M brightness values ranging from 128 to 255, and both N and M are non-negative integers, then the low brightness pixel group has N brightness values value, and the high-brightness pixel group has M brightness values.

In step c, the luminance lookup table is used to map an input pixel luminance to an output pixel luminance, wherein, when the input pixel luminance is not higher than a threshold (eg 127), the output pixel luminance is equal to all the input pixel brightness; and when the input pixel brightness is higher than the threshold, the output pixel brightness is equal to the input pixel brightness minus a brightness reduction amount, and the brightness reduction amount is related to the input pixel brightness proportional to and proportional to the difference. Please refer to FIG. 2 , which shows a luminance conversion curve corresponding to the luminance lookup table, wherein the depression degree of the luminance conversion curve is proportional to the difference.

In step d, the output data of each pen (R, G, B) is used to generate a corresponding current to drive a self-luminous display panel, and the self-luminous display panel may be a micro-LED display panel, a miniature A light emitting diode display panel, a quantum dot light emitting diode display panel or an organic light emitting diode display panel.

According to the above description, the present invention provides a driving circuit. Please refer to FIG. 3 , which shows a block diagram of an embodiment of the driving circuit of the present invention. As shown in FIG. 3 , a driving circuit 100 includes a color gamut conversion unit 110 , a luminance distribution analysis unit 120 , a look-up table generation unit 130 , a luminance adjustment unit 140 , a color gamut inverse conversion unit 150 and a driving unit 160 to A self-luminous display panel 200 executes a current limiting procedure, and the current limiting procedure includes:

(1) The color gamut conversion unit 110 receives RGB data from an RGB input stream RGB _IN , and performs a color gamut conversion on the RGB data to obtain a pixel luminance Y and a pixel chroma D _COLOR in a color space, wherein , the color space can be a color space representing each pixel with a luminance data and a chroma data, for example, the color space can be a YUV space or a YCbCr space, where Y represents the luminance, (U, V) and ( Cb, Cr) are combined to represent chroma.

(2) The brightness distribution analysis unit 120 performs the following operations: receiving a frame of pixel brightness Y and performing a brightness distribution analysis on it to obtain a pixel brightness distribution N(Y) representing the picture data of the previous frame, wherein Y represents a pixel brightness, N represents the number of pixels, that is, with respect to the current RGB input stream RGB _IN , the pixel brightness distribution N(Y) generated by the brightness distribution analysis unit 120 represents the pixel brightness distribution of the RGB data of the previous frame; Pixel brightness distribution N(Y) to obtain a high-brightness pixel group and a low-brightness pixel group, and respectively perform a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a first average value. Two average values, and a subtraction operation is performed on the first average value and the second average value to obtain a difference Y _D . In addition, the high-brightness pixel group and the low-brightness pixel group use a medium brightness value (for example, 128) as a dividing point, that is, pixels greater than or equal to the medium brightness value are classified into the high-brightness pixel group, and less than The pixels of the medium luminance value are classified into the low luminance pixel group. For example, if the pixel brightness distribution has N brightness values ranging from 0 to 127, M brightness values ranging from 128 to 255, and both N and M are non-negative integers, then the low brightness pixel group has N brightness values value, and the high-brightness pixel group has M brightness values.

(3) The lookup table generating unit 130 determines a luminance lookup table LUT according to the difference Y _D , wherein the luminance lookup table LUT is used to map an input luminance to an output luminance, wherein the input luminance is not high At a threshold (eg, 127), the output brightness is equal to the input brightness; and when the input brightness is higher than the threshold, the output brightness is equal to the input brightness minus a tune-down amount, and the tune The _droop is proportional to the input luminance and to the difference YD.

(4) The brightness adjustment unit 140 maps the brightness Y corresponding to one (R, G, B) input data in the current RGB input stream RGB _IN according to the brightness lookup table LUT to generate an output brightness Y _OUT .

(5) The color gamut inverse conversion unit 150 performs the inverse conversion operation of the color gamut conversion on the output luminance Y _OUT and the current pixel chroma D _COLOR to generate an (R, G, B) output data, thereby generating a The RGB output stream is RGB _OUT , wherein the output data of each pen (R, G, B) is used for the driving unit 160 to generate the corresponding analog voltage VA to drive the self _- luminous display panel 200 to generate the corresponding pixel current. In addition, the self-luminous display panel 200 may be a micro-LED display panel, a mini LED display panel, a quantum dot LED display panel or an organic LED display panel.

According to the above description, the present invention further provides a self-luminous display. Please refer to FIG. 4 , which shows a block diagram of an embodiment of the self-luminous display of the present invention. As shown in FIG. 4 , a self-illuminating display 300 has a driving circuit 310 and a self-illuminating display panel 320 , wherein the driving circuit 310 is realized by the driving circuit 100 , and the self-illuminating display panel 320 is realized by the self-illuminating display panel 200 .

By the design disclosed above, the present invention has the following advantages:

1. The adaptive current limiting method of the self-luminous display of the present invention can determine the brightness adjustment distribution of each pixel in a high brightness range according to the brightness average difference between the high brightness group and the low brightness group of a frame of display data, thereby The power consumption of a self-luminous display is further reduced without affecting the chroma content of the picture, and thus its service life is extended.

2. The adaptive current limiting method of the self-luminous display of the present invention can dynamically update the distribution of the brightness reduction amount to instantly provide corresponding high-brightness pixel down-pressing processing for different picture data with different brightness average differences, so as to adapt to It can significantly reduce the power consumption and prolong the service life of self-luminous displays.

What is disclosed in this case is a preferred embodiment, and any partial changes or modifications that originate from the technical ideas of this case and are easily inferred by those who are familiar with the art are within the scope of the patent right of this case.

To sum up, regardless of the purpose, means and effect of this case, it shows that it is completely different from the conventional technology, and its first invention is suitable for practical use, and indeed meets the patent requirements of the invention. Society is to pray for the best.

100: Drive circuit 110: Color Gamut Conversion Unit 120: Brightness distribution analysis unit 130: Lookup table generation unit 140: Brightness adjustment unit 150: color gamut inverse conversion unit 160: Drive unit 200: Self-luminous display panel 300: Self-illuminating display 310: Drive circuit 320: Self-luminous display panel Step a: Perform a color gamut conversion on the RGB data of the previous frame to obtain a pixel brightness distribution in a color space Step b: Counting the pixel brightness distribution to obtain a high-brightness pixel group and a low-brightness pixel group, and performing a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a a second average value, and performing a subtraction operation on the first average value and the second average value to obtain a difference Step c: Determine a luminance lookup table according to the difference and map an input pixel luminance according to the luminance lookup table to generate an output pixel luminance Step d: Inverse conversion of the color gamut conversion is performed on the output pixel luminance and an input pixel chroma to generate an (R, G, B) output data

FIG. 1 is a flowchart illustrating an embodiment of an adaptive current limiting method for a self-luminous display of the present invention. FIG. 2 illustrates a luminance conversion curve corresponding to the luminance lookup table described in the flow shown in FIG. 1 . FIG. 3 is a block diagram illustrating an embodiment of the driving circuit of the present invention. FIG. 4 shows a block diagram of one embodiment of the display of the present invention.

Step a: Perform a color gamut conversion on the RGB data of the previous frame to obtain a pixel brightness distribution in a color space

Step b: Counting the pixel brightness distribution to obtain a high-brightness pixel group and a low-brightness pixel group, and performing a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a a second average value, and performing a subtraction operation on the first average value and the second average value to obtain a difference

Step c: Determine a luminance lookup table according to the difference and map an input pixel luminance according to the luminance lookup table to generate an output pixel luminance

Step d: Inverse conversion of the color gamut conversion is performed on the output pixel luminance and an input pixel chroma to generate an (R, G, B) output data

Claims (10)

An adaptive current limiting method for a self-luminous display, comprising: performing a color gamut conversion on RGB data of a previous frame to obtain a pixel brightness distribution in a color space; counting the pixel brightness distribution to obtain a high-brightness pixel group; A low-brightness pixel group, and a weighted average calculation is performed on the high-brightness pixel group and the low-brightness pixel group to obtain a first average value and a second average value, and the first average value and the second average value are obtained. performing a subtraction operation on the average value to obtain a difference value; determining a luminance lookup table according to the difference value and mapping an input pixel luminance according to the luminance lookup table to generate an output pixel luminance; and the output pixel luminance and an input pixel color The inverse conversion of the color gamut conversion is performed to generate an (R, G, B) output data; wherein the luminance lookup table is used to map an input luminance to an output luminance, wherein the input luminance is not high At a threshold, the output brightness is equal to the input brightness; and when the input brightness is higher than the threshold, the output brightness is equal to the input brightness minus a reduction amount, and the reduction amount is the same as the input brightness. The input brightness is proportional to and proportional to the difference. The adaptive current limiting method for a self-luminous display as described in claim 1, wherein the color space represents each pixel with a luminance data and a chromaticity data. The adaptive current limiting method for a self-luminous display as described in claim 2, wherein the color space is a YUV space or a YCbCr space. The adaptive current limiting method for a self-luminous display as described in claim 1, wherein the high-brightness pixel group and the low-brightness pixel group use a medium brightness value as a dividing point, that is, greater than or equal to the Pixels with a medium brightness value are classified into the high-brightness pixel group, and pixels with a lower brightness value are classified into the low-brightness pixel group. The adaptive current limiting method for a self-luminous display according to the claim 1, wherein the (R, G, B) output data of each pen is used to generate a corresponding current to drive a self-luminous display panel, The self-luminous display panel is composed of a micro-LED display panel, a mini LED A display panel selected from the group consisting of a volume display panel, a quantum dot light-emitting diode display panel and an organic light-emitting diode display panel. A driving circuit includes a color gamut conversion unit, a luminance distribution analysis unit, a look-up table generation unit, a luminance adjustment unit and a color gamut inverse conversion unit to perform a current limiting procedure on a self-luminous display panel, the current limiting procedure comprising: : The color gamut conversion unit receives RGB data from an RGB input stream, and performs a color gamut conversion on the RGB data to obtain a pixel luminance and a pixel chroma in a color space; the luminance distribution analysis unit performs the following Operation: receiving a frame of the pixel brightness and performing a brightness distribution analysis on it to obtain a pixel brightness distribution N(Y) representing the previous frame of picture data, where Y represents the pixel brightness and N represents the number of pixels; and Counting the pixel brightness distribution N(Y) to obtain a high-brightness pixel group and a low-brightness pixel group, and performing a weighted average calculation on the high-brightness pixel group and the low-brightness pixel group respectively to obtain a first average value and a second average value, and performing a subtraction operation on the first average value and the second average value to obtain a difference value; the lookup table generating unit determines a luminance lookup table according to the difference, wherein the luminance lookup table is used to map a pixel brightness to an output brightness, wherein, when the pixel brightness is not higher than a threshold, the output brightness is equal to the pixel brightness; and when the pixel brightness is higher than the threshold , the output brightness is equal to the pixel brightness minus a reduction amount, and the reduction amount is proportional to the pixel brightness and the difference; the brightness adjustment unit maps the current brightness according to the brightness lookup table the pixel luminance to generate the output luminance; and the color gamut inverse conversion unit performs an inverse conversion operation of the color gamut conversion on the output luminance and the current pixel chroma to generate a (R, G, B) Output data, thereby generating an RGB output stream. The driving circuit as described in claim 6, wherein the color space is a YUV space or a YCbCr space. The driving circuit as described in claim 6, wherein the high-brightness pixel group and the low-brightness pixel group use a medium brightness value as a dividing point, that is, pixels greater than or equal to the medium brightness value are classified as Similar to the high-brightness pixel group, pixels less than the medium-brightness value are classified as the low-brightness pixel group of pixels. The driving circuit of claim 6, wherein the (R, G, B) output data of each pen is used to generate a corresponding current to drive the self-luminous display panel, and the self-luminous display The panel is a display panel selected from the group consisting of a micro light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel and an organic light emitting diode display panel. A display, which has the driving circuit and a self-luminous display panel as described in any one of claims 6 to 9 of the patent application scope.

Images