Low-illumination image restoration and display optimization method for electronic paper display

Abstract

The invention discloses a low-illumination image restoration and display optimization method for electronic paper display, and the method comprises the steps: obtaining each display gray-scale value of a display picture signal corresponding to a first image in response to the display picture signal received by an electronic paper display; judging whether the first image is a low-illumination image or not according to the display gray-scale value; in response to the fact that the first image is a low-illumination image, obtaining a first temperature corresponding to the display pixel according to the display gray-scale value; controlling a heating resistor to heat the display pixel to a first temperature; and applying a corresponding potential to the upper-layer electrode and / or the lower-layer electrode to enable the display pixel to increase the display gray-scale value correspondingly displayed under the influence of the first temperature, so as to perform histogram equalization on the whole first image displayed by the electronic paper display and increase the global contrast of the first image. According to the invention, restoration and display optimization can be effectively carried out on the low-illumination image, and the display effect of the low-illumination image is improved.

Description

Technical Field

[0001] The present invention relates to the field of electronic paper display, and in particular to a low-light image restoration and display optimization method for electronic paper display. Background Art

[0002] The flexibility of display panels is the main development direction of new display technologies. Electronic paper display technology has the characteristics of ultra-low power consumption and comfortable reading in outdoor light environments. It is one of the ideal carriers of portable and wearable flexible display terminals. Therefore, its flexibility is currently a hot topic in international research. In recent years, electronic paper display devices have attracted much attention due to their advantages such as paper-like appearance, low power consumption, and environmental protection. Compared with electrophoretic electronic paper, electrowetting electronic paper has a faster response speed and can achieve color display. It is an electronic paper display that can achieve high-resolution video playback.

[0003] Electrowetting electronic paper display technology changes the state of pixels by applying voltage between the plates to shrink or spread the ink. The pixel conversion is very fast, which can achieve high-resolution video playback. Compared with traditional LCD and other display methods, the backlight of traditional LCD consumes 90% of the energy, and the efficiency of its reflective layer is also very low; electrowetting technology does not require backlight, the reflective layer efficiency can reach 40%, and the power consumption is also lower. In addition, electrowetting technology uses oil film as raw material and does not require the complex chemical components used in LCD, so it is more stable in extreme environments such as low temperature. Electrowetting display panels can display using ambient light, and electronic devices that are often used in sunlight are more suitable for using electrowetting display panels. Electrowetting panels also have the advantages of simple structure, flexible display, high brightness, high contrast and wide viewing angle.

[0004] However, when the electronic paper display is used to display low-light images, the display quality and effect will be relatively poor. This is because low-light images are taken under weak ambient light conditions, and the image quality itself is low. In addition, the electronic paper display does not restore and optimize the image, which leads to poor display quality and effect. Summary of the invention

[0005] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide a low-light image restoration and display optimization method for electronic paper display, aiming to restore and optimize the display of low-light images and improve the display effect of low-light images.

[0006] To achieve the above object, the present invention provides a low-light image restoration and display optimization method for electronic paper display, the method comprising:

[0007] Step S1, in response to the electronic paper display receiving a display image signal, obtaining each display grayscale value of the first image corresponding to the display image signal; wherein the electronic paper display comprises a plurality of display pixels for displaying each of the display grayscale values, the display pixel comprises an upper electrode and a lower electrode, primary color ink is arranged between the upper electrode and the lower electrode, the upper electrode and the lower electrode are used to apply different potentials to generate a potential difference so that the primary color ink changes its hydrophobicity to control the grayscale value, and a temperature rising resistor is arranged under the display pixel;

[0008] Step S2, judging whether the first image is a low-light image according to the display grayscale value, and if so, proceeding to step S3; if not, applying a corresponding potential to the upper electrode and / or the lower electrode, so that the display pixel directly displays the corresponding display grayscale value;

[0009] Step S3, in response to the first image being a low-light image, obtaining a first temperature corresponding to the display pixel according to the display grayscale value; controlling the temperature-raising resistor to heat the display pixel to the first temperature, so as to intensify the molecular thermal motion in the primary color ink and improve the sensitivity of the hydrophobicity of the primary color ink to the change of the potential difference;

[0010] Step S4, applying a corresponding potential to the upper electrode and / or the lower electrode so that the display pixel amplifies the display grayscale value corresponding to the display under the influence of the first temperature, and then performing histogram equalization on the first image displayed by the electronic paper display as a whole to increase the global contrast of the first image.

[0011] Optionally, step S2 includes:

[0012] Determine whether each of the display grayscale values ​​is lower than the first preset grayscale value. If so, the first image is a low-light image, and enters step S3; if not, the first image is not a low-light image, and a corresponding potential is applied to the upper electrode and / or the lower electrode so that the display pixel directly displays the corresponding display grayscale value.

[0013] Optionally, obtaining the first temperature corresponding to the display pixel according to the display grayscale value in step S3 includes:

[0014] Obtaining a maximum grayscale value among the displayed grayscale values;

[0015] The first temperature corresponding to the display pixel is determined according to the maximum grayscale value; wherein, the larger the maximum grayscale value is, the smaller the first temperature is.

[0016] Optionally, the display pixel further includes black ink, and the black ink is disposed below the primary color ink, and the black ink is used to increase contrast.

[0017] Optionally, the primary color ink material in the display pixel includes perylenetetracarboxamide diimide and condensed cyclic ketone.

[0018] Optionally, the heating resistor heats the display pixels together so that the display pixels are at the same first temperature.

[0019] Optionally, the display pixels include red display pixels, green display pixels and blue display pixels divided into different groups according to the colors corresponding to the primary color inks, and the display pixel groups of three different colors perform a combination display of three primary colors.

[0020] Optionally, the hydrophobicity of the primary color ink is proportional to the potential difference; when the display pixel is not driven, the applied potential difference is greater than the first threshold potential difference, so that the hydrophobicity of the primary color ink reaches the highest level and gathers under the upper electrode.

[0021] Optionally, the hydrophobicity of the primary color ink is inversely proportional to the potential difference; when the display pixel is not driven, the applied potential difference is zero, so that the hydrophobicity of the primary color ink reaches the highest and gathers under the upper electrode.

[0022] Beneficial effects of the present invention: The present invention heats the primary color ink in the display pixel through a temperature-raising resistor, thereby intensifying the molecular thermal motion in the primary color ink, and further increasing the sensitivity of the hydrophobicity of the primary color ink to the change in potential difference. In other words, increasing the temperature makes it easier for the ink opening ratio (grayscale value) to change with the change in potential difference, and the various grayscale values ​​corresponding to the original low-light image are amplified in the display pixel of the electronic paper display, achieving physical histogram equalization and increasing the global contrast of the low-light image. In this way, the present invention effectively restores and optimizes the display of low-light images, thereby improving the display quality of low-light images. At the same time, compared with the prior art that uses additional image processing software to restore low-light images and then sends them to the electronic paper display for display, the electronic paper display of the present invention can restore and optimize the display by itself, so that the electronic paper can improve the display quality without the help of the outside world.

[0023] In summary, the present invention can effectively restore and optimize the display of low-light images, thereby improving the display effect of low-light images. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flowchart of a method for low-light image restoration and display optimization for electronic paper display provided by a specific embodiment of the present invention;

[0025] Figure 2 is a schematic structural diagram of a display pixel provided by a specific embodiment of the present invention;

[0026] Figure 3 It is a schematic diagram comparing ink opening ratios of display pixels at different temperatures provided by a specific embodiment of the present invention. DETAILED DESCRIPTION

[0027] The present invention discloses a method for low-light image restoration and display optimization for electronic paper display. Those skilled in the art can refer to the content of this article and appropriately improve the technical details. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0028] The applicant has found through research that when the electronic paper display is used to display low-light images, the display quality and effect will be relatively poor. Because the low-light images are taken under weak ambient light, the image quality itself is low, and the electronic paper display does not restore and optimize the display, which will lead to poor display quality and effect. The existing technology can only compensate for the lack of display quality by performing additional image processing on the low-light images and sending them to the electronic paper display for display. However, the electronic paper display itself cannot restore and optimize the display of low-light images.

[0029] Therefore, an embodiment of the present invention provides a low-light image restoration and display optimization method for electronic paper display, such as Figure 1 As shown, the method includes:

[0030] Step S1: in response to the electronic paper display receiving a display picture signal, obtaining each display grayscale value of a first image corresponding to the display picture signal.

[0031] Among them, the electronic paper display includes multiple display pixels for displaying each display grayscale value, the display pixel includes an upper electrode and a lower electrode, primary color ink is arranged between the upper electrode and the lower electrode, the upper electrode and the lower electrode are used to apply different potentials to generate a potential difference so that the primary color ink changes its hydrophobicity to control the grayscale value, and a temperature rising resistor is arranged under the display pixel.

[0032] In this specific embodiment, the display pixel structure can be as follows Figure 2 As shown, the display pixel includes an upper electrode and a lower electrode, primary color ink is arranged between the upper electrode and the lower electrode, and a temperature rising resistor is arranged under the display pixel.

[0033] It should be noted that the display image signal in this embodiment is generally not processed by other image processing software.

[0034] Step S2, judging whether the first image is a low-light image according to the display grayscale value, if so, proceeding to step S3; if not, applying corresponding potentials to the upper electrode and / or the lower electrode so that the display pixel directly displays the corresponding display grayscale value.

[0035] It should be noted that when the first image is not a low-light image, it means that the quality of the first image is not affected by light, and the first image is directly displayed normally without the need for a heating resistor to heat the display pixels. ;

[0036] In this specific embodiment, step S2 includes:

[0037] Determine whether each display grayscale value is lower than the first preset grayscale value. If so, the first image is a low-light image, and enter step S3; if not, the first image is not a low-light image, and a corresponding potential is applied to the upper electrode and / or the lower electrode so that the display pixel directly displays the corresponding display grayscale value.

[0038] It should be noted that low-light images have low grayscale values ​​due to the weak ambient light in which they are shot. Therefore, a threshold is set in this embodiment. When all grayscale values ​​in the first image do not exceed the threshold, it can be determined to be a low-light image.

[0039] Step S3, in response to the first image being a low-light image, obtaining a first temperature corresponding to the display pixel according to the display grayscale value; controlling the temperature rising resistor to heat the display pixel to the first temperature to intensify the molecular thermal motion in the primary color ink and improve the sensitivity of the hydrophobicity of the primary color ink to the change of the potential difference.

[0040] It should be noted that when liquid molecules may obtain enough energy to overcome the interaction force between the molecules on the solid surface, the more intense the molecular thermal motion in the primary ink is, the easier it is for its surface tension (hydrophobicity) to be changed by the potential difference. Therefore, the higher the temperature, the more sensitive the hydrophobicity of the primary ink is to the change of the potential difference.

[0041] It is worth mentioning that, under all temperature conditions in the embodiments of the present invention, at the convergence potential, the primary color inks are all gathered under the upper electrode in the shape of spherical droplets.

[0042] Under the same potential difference at different temperatures, the opening ratio of the primary color ink in the two display pixels is as follows: Figure 3 As shown, the first temperature is lower than the second temperature. Figure 3 It can be seen that when the temperature is higher, the ink opening rate changes more.

[0043] In step S3, obtaining a first temperature corresponding to a display pixel according to the display grayscale value includes:

[0044] Obtaining the maximum grayscale value among various displayed grayscale values;

[0045] According to the maximum grayscale value, a first temperature corresponding to the display pixel is determined; wherein, the larger the maximum grayscale value is, the smaller the first temperature is.

[0046] It should be noted that the image restoration and display optimization in the embodiment of the present invention is based on histogram equalization, so the smaller the maximum grayscale value is, the greater the degree of stretching required is, and the higher the first temperature is.

[0047] Step S4, applying corresponding potentials to the upper electrode and / or the lower electrode so that the display pixel amplifies the corresponding display grayscale value under the influence of the first temperature, thereby performing histogram equalization on the first image displayed by the electronic paper display as a whole to increase the global contrast of the first image.

[0048] It should be noted that the embodiment of the present invention realizes the restoration and display optimization of low-light images by the electronic paper display itself through a physical heating method.

[0049] In this specific embodiment, the display pixel further includes black ink, which is disposed under the primary color ink and is used to increase contrast.

[0050] It should be noted that in this embodiment, the display pixel is a double-layer ink structure, and the contrast is increased by the black ink below to improve the display quality of the image.

[0051] In this specific embodiment, the primary color ink materials in the display pixel include perylenetetracarboxamide diimide and condensed cyclic ketone.

[0052] It should be noted that these two materials are ink materials used in the electrowetting electronic paper of the embodiment of the present invention, and the sensitivity between their hydrophobicity and potential difference changes due to the influence of temperature.

[0053] In this specific embodiment, the heating resistor heats each display pixel together, so that each display pixel is at the same first temperature.

[0054] It should be noted that the common heating is to ensure the consistency of histogram equalization and ensure image quality.

[0055] In this specific embodiment, the display pixels include red display pixels, green display pixels and blue display pixels according to the colors corresponding to the primary color inks, and three display pixel groups with different colors perform a combination display of three primary colors.

[0056] It should be noted that the RGB primary colors are a commonly used color combination in displays, which can restore a variety of colors and ensure pixel display effects.

[0057] In this specific embodiment, the hydrophobicity of the primary color ink is proportional to the potential difference; when the display pixel is not driven, the applied potential difference is greater than the first threshold potential difference so that the hydrophobicity of the primary color ink reaches the highest level and gathers under the upper electrode.

[0058] In another specific embodiment, the hydrophobicity of the primary color ink is inversely proportional to the potential difference; when the display pixel is not driven, the applied potential difference is zero, so that the hydrophobicity of the primary color ink reaches the highest and gathers under the upper electrode.

[0059] It should be noted that both of these characteristics may be applied to the embodiments of the present invention, wherein the hydrophobicity of the primary color ink is inversely proportional to the potential difference, which is commonly used.

[0060] The embodiment of the present invention heats the primary color ink in the display pixel through a temperature-raising resistor, so that the molecular thermal motion in the primary color ink is intensified, thereby increasing the sensitivity of the hydrophobicity of the primary color ink to the change in potential difference. In other words, the increase in temperature makes it easier for the ink opening rate (grayscale value) to change with the change in potential difference. The various grayscale values ​​corresponding to the original low-light image are amplified in the display pixel of the electronic paper display, realizing the physical histogram equalization and increasing the global contrast of the low-light image. In this way, the embodiment of the present invention effectively restores and optimizes the display of low-light images, thereby improving the display quality of low-light images. At the same time, compared with the prior art that uses additional image processing software to restore low-light images and then sends them to the electronic paper display for display, the electronic paper display of the embodiment of the present invention can restore and optimize the display by itself, so that the electronic paper can improve the display quality without the help of the outside world.

[0061] In summary, the embodiments of the present invention can effectively restore and optimize the display of low-light images, thereby improving the display effect of low-light images.

[0062] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0063] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0064] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A low-light image restoration and display optimization method for electronic paper display, It is characterized in that The method comprises: Step S1, in response to the electronic paper display receiving a display image signal, obtaining each display grayscale value of the first image corresponding to the display image signal; wherein the electronic paper display comprises a plurality of display pixels for displaying each of the display grayscale values, the display pixel comprises an upper electrode and a lower electrode, primary color ink is arranged between the upper electrode and the lower electrode, the upper electrode and the lower electrode are used to apply different potentials to generate a potential difference so that the primary color ink changes its hydrophobicity to control the grayscale value, and a temperature rising resistor is arranged under the display pixel; Step S2, judging whether the first image is a low-light image according to the display grayscale value, and if so, proceeding to step S3; if not, applying a corresponding potential to the upper electrode and / or the lower electrode, so that the display pixel directly displays the corresponding display grayscale value; Step S3, in response to the first image being a low-light image, obtaining a first temperature corresponding to the display pixel according to the display grayscale value; controlling the temperature-raising resistor to heat the display pixel to the first temperature, so as to intensify the molecular thermal motion in the primary color ink and improve the sensitivity of the hydrophobicity of the primary color ink to the change of the potential difference; Step S4, applying a corresponding potential to the upper electrode and / or the lower electrode so that the display pixel amplifies the display grayscale value corresponding to the display under the influence of the first temperature, and then performing histogram equalization on the first image displayed by the electronic paper display as a whole to increase the global contrast of the first image.

2. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The step S2 comprises: Determine whether each of the display grayscale values ​​is lower than the first preset grayscale value. If so, the first image is a low-light image, and enters step S3; if not, the first image is not a low-light image, and a corresponding potential is applied to the upper electrode and / or the lower electrode so that the display pixel directly displays the corresponding display grayscale value.

3. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The step S3 of obtaining the first temperature corresponding to the display pixel according to the display grayscale value includes: Obtaining a maximum grayscale value among the displayed grayscale values; The first temperature corresponding to the display pixel is determined according to the maximum grayscale value; wherein, the larger the maximum grayscale value is, the smaller the first temperature is.

4. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The display pixel further includes black ink, which is disposed under the primary color ink and is used to increase contrast.

5. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The primary color ink material in the display pixel includes perylenetetracarboxamide diimide and condensed cyclic ketone.

6. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The heating resistor heats the display pixels together, so that the display pixels are at the same first temperature.

7. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The display pixels include red display pixels, green display pixels and blue display pixels according to the colors corresponding to the primary color inks, and the display pixel groups of three different colors perform three-primary color combination display.

8. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The hydrophobicity of the primary color ink is proportional to the potential difference; when the display pixel is not driven, the applied potential difference is greater than the first threshold potential difference, so that the hydrophobicity of the primary color ink reaches the highest and gathers under the upper electrode.

9. The low-light image restoration and display optimization method for electronic paper display according to claim 1, It is characterized in that The hydrophobicity of the primary color ink is inversely proportional to the potential difference; when the display pixel is not driven, the applied potential difference is zero, so that the hydrophobicity of the primary color ink reaches the highest and is gathered under the upper electrode.

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