Sub-pixel rendering method for display panel

Abstract

The present invention relates to a sub-pixel rendering method for a display panel, which determines a sampling position according to a sub-pixel arrangement position, thereby converting an input image according to a human eye visual model to generate corresponding adjusted luminance data and sampling a plurality of adjusted luminance values ​​of the aforementioned adjusted luminance data through the sampling position, thereby generating corresponding target grayscale data, thereby avoiding input image distortion.

Description

Technical Field

[0001] The present invention relates to a rendering method, and more particularly to a sub-pixel rendering method applied to a display panel. Background Art

[0002] In a general display panel, the sub-pixel structure is arranged in a matrix, and each sub-pixel structure can display one of red, green and blue. Further, the sub-pixel structures of the three colors of red, green and blue can form a pixel. However, not all display panels have three sub-pixel structures in one pixel unit, resulting in poor display quality.

[0003] In order to solve the above-mentioned problem of poor display quality, in the prior art, some industry players have jointly proposed a primary color sub-pixel rendering technology, which is to design a specific sub-pixel rendering algorithm for a specific primary color sub-pixel arrangement. However, the existing sub-pixel rendering algorithm does not take into account the human eye visual model, that is, it ignores the visual perception of the human eye.

[0004] Based on the above problems, the present invention provides a sub-pixel rendering method for a display panel, which converts the input grayscale image of the input image according to the human eye visual model to obtain adjusted luminance data, thereby obtaining better target grayscale data, so that the grayscale image displayed by the display panel can meet the visual perception of the human eye. Summary of the invention

[0005] An object of the present invention is to provide a sub-pixel rendering method for a display panel, which utilizes input grayscale data of an input image converted according to a human eye visual model to generate corresponding adjusted luminance data, and samples the corresponding adjusted luminance value according to a sampling position corresponding to a sub-pixel arrangement position, thereby obtaining a target grayscale value that meets the visual perception of a person.

[0006] The present invention discloses a sub-pixel rendering method for a display panel, which first determines a plurality of sampling positions according to a plurality of sub-pixel arrangement positions, and converts an input grayscale data of an input image according to a human eye vision model to generate an adjusted luminance data, and then samples a plurality of adjusted luminance values ​​of the adjusted luminance data according to the sampling positions, and finally generates a target grayscale data according to the sampled plurality of adjusted luminance values, wherein the target grayscale data includes a plurality of target grayscale values ​​corresponding to the plurality of sub-pixels, thereby avoiding distortion of the input image and making the target grayscale value conform to the visual perception of the human eye. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a block diagram of an embodiment of a sub-pixel rendering method of the present invention;

[0008] Figure 2 is a flow chart of an embodiment of a sub-pixel rendering method of the present invention;

[0009] Figure 3 A schematic diagram of sub-pixel arrangement of an embodiment of a sub-pixel rendering method of the present invention;

[0010] Figure 4 A flowchart of human eye vision conversion of an embodiment of the sub-pixel rendering method of the present invention;

[0011] Figure 5 A schematic diagram of conversion steps of an embodiment of a sub-pixel rendering method of the present invention;

[0012] Figure 6 is a graph of grayscale versus brightness according to an embodiment of the sub-pixel rendering method of the present invention;

[0013] Figure 7 A flow chart of sampling steps of an embodiment of a sub-pixel rendering method of the present invention;

[0014] Figure 8 A schematic diagram of sampling steps of an embodiment of a sub-pixel rendering method of the present invention; and

[0015] Fig. 9 FIG. 4 is a schematic diagram of conversion from brightness to grayscale according to an embodiment of a sub-pixel rendering method of the present invention.

[0016] Reference Numbers

[0017] 10 Display device

[0018] 12 Operational Circuit

[0019] 14. Driving circuit

[0020] 16 Display Panel

[0021] 162 sub-pixels

[0022] 1622 first sub-pixel

[0023] 1624 second sub-pixel

[0024] 1626 third sub-pixel

[0025] 164 sampling positions

[0026] 20 microprocessor units

[0027] ADB adjusts brightness data

[0028] B1 input brightness value

[0029] B2 adjusts the brightness value

[0030] B3 Sampling brightness value

[0031] B4 compensation brightness value

[0032] CB compensation brightness data

[0033] CV grayscale to brightness curve

[0034] DR drive signal

[0035] EQ1 forward function

[0036] EQ2 reverse function

[0037] GD target grayscale data

[0038] G1 input grayscale value

[0039] G2 target grayscale value

[0040] HV human vision model

[0041] IN Input image

[0042] ING input grayscale data

[0043] INB input brightness data

[0044] SEN sensor signal

[0045] SPB sampled luminance data

[0046] Steps S10-S40 DETAILED DESCRIPTION

[0047] In order to enable you, the examiner, to have a further understanding and recognition of the features and effects achieved by the present invention, embodiments and accompanying descriptions are provided as follows:

[0048] In view of the fact that the conventional sub-pixel rendering algorithm cannot meet the visual perception of the human eye, the present invention proposes a sub-pixel rendering method for a display panel, which can obtain better target grayscale data so that the grayscale image displayed by the display panel can meet the visual perception of the human eye.

[0049] Certain words are used in the specification and claims to refer to specific components. However, those skilled in the art should understand that manufacturers may use different terms to refer to the same component. Moreover, the specification and claims do not use the difference in name as a way to distinguish components, but use the overall technical difference of the components as the criterion for distinction. The term "including" mentioned throughout the specification and claims is an open term and should be interpreted as "including but not limited to". Furthermore, the term "coupled" includes direct and indirect connection means. Therefore, if the text describes a first device coupled to a second device, it means that the first device can be directly connected to the second device, or can be indirectly connected to the second device through other devices or other connection means.

[0050] The following will further describe the characteristics and structure of a sub-pixel rendering method for a display panel disclosed in the present invention:

[0051] First, see Figure 1 , which is a block diagram of an embodiment of the sub-pixel rendering method of the present invention. As shown in the figure, the display device 10 to which the sub-pixel rendering method of the display panel of the present invention is applied includes an operation circuit 12, a driving circuit 14 and a display panel 16. The operation circuit 12 receives an input image IN input from a micro-processing unit 20 (for example: the micro-processing unit 20 inputs a digital image to the operation circuit 12), and performs a sub-pixel rendering operation RP of the input image IN, thereby generating a corresponding target grayscale data GD to the driving circuit 14, and the driving circuit 14 generates a corresponding driving signal DR to the display panel 16 according to the target grayscale data GD and drives the display panel 16 to display the grayscale image corresponding to the input image IN. The operation circuit 12 referred to in this embodiment is a circuit that can have logic and floating-point operation capabilities, and the operation circuit 12 of the present invention can be further integrated into the driving circuit 14.

[0052] See also Figure 2 , which is a flow chart of an embodiment of the sub-pixel rendering method of the present invention. As shown in the figure, the sub-pixel rendering method of the present invention refers to the operation processing process of the operation circuit 12, and its steps include:

[0053] Step S10: determining a sampling position according to the sub-pixel arrangement position;

[0054] Step S20: converting the input grayscale data of the input image according to the human eye vision model to generate adjusted brightness data;

[0055] Step S30: sampling and adjusting the brightness value of the brightness data according to the sampling position; and

[0056] Step S40: Generate target grayscale data according to the sampled adjusted luminance value.

[0057] In step S10, the calculation circuit 12 obtains a plurality of sampling positions 164 (eg, Figure 3 As shown), the operation circuit 12 determines the number of the corresponding sampling positions 164 according to the arrangement positions of the sub-pixels 162 and a display resolution of the display panel 16, such as Figure 3As shown, the sub-pixels 162 of the present invention in this embodiment include multiple first sub-pixels 1622, multiple second sub-pixels 1624 and multiple third sub-pixels 1626. In this embodiment, the first sub-pixels 1622 are red pixels, the second sub-pixels 1624 are blue pixels, and the third sub-pixels 1626 are green pixels. The first sub-pixels 1622, the second sub-pixels 1624 and the third sub-pixels 1626 have their corresponding sampling positions 164 respectively, but the present invention is not limited to this and can be further applied to special display devices with other display conditions, for example: display panels 16 with various sub-pixel arrangements, so that the operation circuit 12 determines the corresponding sampling position 164 according to the location of the sub-pixels 162.

[0058] Next, in step S20, the operation circuit 12 converts the input grayscale value G1 (eg, Figure 5 As shown), Figure 4 As shown, step S20 comprises the following steps:

[0059] Step S22: converting the input grayscale data according to the grayscale-to-luminance curve to generate input luminance data; and

[0060] Step S24: Generate adjusted luminance data according to the forward function of the human vision model and the input luminance data.

[0061] In step S22, if Figure 5 As shown, the input grayscale data ING of the input image IN includes the input grayscale values ​​G1. The operation circuit 12 is based on Figure 6 A gray-scale-to-brightness curve CV shown converts the input gray-scale values ​​G1 into a plurality of input brightness values ​​B1, thereby generating corresponding input brightness data INB.

[0062] In step S24, refer to Figure 5 The operation circuit 12 adjusts the input luminance values ​​B1 of the input luminance data INB according to the forward function EQ1 of the human eye vision model HV, and generates the adjusted luminance data ADB, wherein the adjusted luminance data ADB includes the adjusted luminance values ​​B2. In this embodiment, the operation circuit 12 uses the forward function EQ1 of the human eye vision model HV as a sampling function, samples the input luminance values ​​B1, and the sampling process is similar to the convolution operation, thereby obtaining the adjusted luminance values ​​B2. The human eye vision model HV described in the present invention is a function of space, wavelength, environment and physiology, which determines the pupil size and the brightness and chromaticity adaptability of the optic nerve based on ambient light.

[0063] Next, in step S30, the operation circuit 12 samples the adjusted brightness values ​​B2 according to the sampling positions 164 corresponding to the sub-pixels 162. Figure 7 As shown, step S30 may further include

[0064] Step S32: adjusting the brightness value according to the sampling position; and

[0065] Step S35: Compensate the sampled luminance value according to the inverse function of the human eye vision model.

[0066] In step S32, if Figure 8 As shown, the operation circuit 12 samples the adjusted luminance values ​​B2 corresponding to the input grayscale values ​​G1 according to the sampling positions 164 corresponding to the sub-pixels 162, thereby obtaining the sampled luminance values ​​B3, and thus generating the corresponding sampled luminance data SPB, that is, the sampling positions 164 corresponding to the arrangement positions of the sub-pixels 162 sample the adjusted luminance values ​​B2 at the corresponding positions, and obtain the corresponding sampled luminance values ​​B3, thereby generating the sampled luminance data SPB. Since the number of the input grayscale values ​​G1 of the input image IN is generally greater than the number of the sub-pixels 162 of the display panel 16, and each input grayscale value G1 has its own position (such as Figure 3 As shown in FIG. 1 , the different resolutions of the input image IN means that the number of input grayscale values ​​G1 of the input image IN is different, so the positions of the sampling positions 164 will also change accordingly. For example, the greater the resolution, the more input grayscale values ​​G1 are, and accordingly, the more input grayscale values ​​G1 are distributed between the sampling positions 164. The smaller the resolution, the fewer input grayscale values ​​G1 are, and accordingly, the fewer input grayscale values ​​G1 are distributed between the sampling positions 164. Therefore, the operation circuit 12 is based on the display screen. The resolution of the display panel 16 and the arrangement positions of the sub-pixels 162 constitute the sampling positions 164 that sample the corresponding adjusted luminance values ​​B2, that is, the operation circuit 12 samples an adjusted luminance value B2 corresponding to each sub-pixel 162 at its position. Thus, even if the resolution of the display panel 16 is different from the number of sub-pixels corresponding to the input image IN, the driving circuit 14 can still drive the display panel 16 to display the grayscale image corresponding to the input image IN according to the target grayscale data GD.

[0067] In step S35, the operation circuit 12 compensates the sampled luminance values ​​B3 according to the inverse function EQ2 of the human visual model HV, thereby generating a plurality of corresponding compensated luminance values ​​B4, thereby generating corresponding compensated luminance data CB. In further detail, the operation circuit 12 samples the luminance values ​​around each sampling position 164 as a center point, and compensates the luminance value of each sampling position 164 according to the inverse function EQ2, thereby compensating the sampled luminance values ​​B3, thereby generating the corresponding compensated luminance values ​​B4.

[0068] Then, in step S40, Fig. 9 As shown, the operation circuit 12 is based on Figure 5 The grayscale-to-brightness curve CV shown in FIG. 1 converts the compensated brightness data CB into the target grayscale data GD. That is, the operation circuit 12 converts the compensated brightness data CB into the target grayscale data GD according to the grayscale-to-brightness curve CV shown in FIG. Figure 6 The grayscale-to-brightness curve CV shown converts the compensated brightness values ​​B4 into a plurality of target grayscale values ​​G2, thus completing low-distortion image rendering. Therefore, the driving circuit 14 generates a corresponding driving signal DR to drive the display panel 16 according to the target grayscale data GD.

[0069] In addition, in step S24, refer to Figure 5 The present invention may further include a sensor 122 coupled to the operation circuit 12. The sensor 122 senses the state of the external environment and provides a sensing signal SEN to the operation circuit 12, thereby correcting the forward function EQ1 of the human eye visual model HV, so that the forward function EQ1 conforms to the state of the external environment. For example, different ambient illumination will cause the forward function EQ1 to be different, that is, the operation circuit 12 dynamically corrects the forward function EQ1 according to the environmental conditions.

[0070] In summary, the sub-pixel rendering method of the display panel of the present invention converts the input grayscale data of the input image into input luminance data and adjusts it according to the forward function of the human eye visual model to generate corresponding adjusted luminance data; and samples the adjusted luminance data according to the sampling position to obtain sampled luminance data, and then compensates the sampled luminance data according to the inverse function of the human eye visual model to obtain compensated luminance data, thereby generating target grayscale data, and providing a driving circuit to drive the display panel according to the target grayscale value of the target grayscale data. In this way, not only a target grayscale value that meets the resolution of the display panel is provided to drive the sub-pixels of the display panel, but also the grayscale image displayed by the display panel meets the perception of human eye vision.

Claims

1. A sub-pixel rendering method for a display panel, characterized in that: Include: Determining a plurality of sampling positions according to a plurality of sub-pixel arrangement positions; Converting an input grayscale data of an input image according to a grayscale-to-luminance curve to generate an input luminance data, wherein the input luminance data includes a plurality of input luminance values, and the input grayscale data includes a plurality of input grayscale values; Generate an adjusted luminance data according to a forward function of a human eye vision model and the input luminance data, wherein the adjusted luminance data includes a plurality of adjusted luminance values; sampling the plurality of adjusted brightness values ​​of the adjusted brightness data according to the plurality of sampling positions; as well as A target grayscale data is generated according to the sampled plurality of adjusted luminance values. The target grayscale data includes a plurality of target grayscale values ​​corresponding to the plurality of sub-pixels.

2. The sub-pixel rendering method according to claim 1, wherein: Also includes: The state of the sensing environment is used to correct the forward function of the human eye vision model.

3. The sub-pixel rendering method according to claim 1, wherein: Also includes: The sampled plurality of adjusted luminance values ​​are compensated according to an inverse function of the human eye vision model, and the plurality of target grayscale values ​​are generated according to the compensated plurality of adjusted luminance values.

4. The sub-pixel rendering method according to claim 1, wherein: Also includes: The target grayscale data is generated by converting the plurality of adjusted luminance values ​​sampled according to a grayscale-to-luminance curve.

5. The sub-pixel rendering method according to claim 1, wherein: Also includes: The plurality of sampling positions are determined according to the plurality of sub-pixel arrangement positions and a display resolution of the display panel.

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