Display device and display method

Abstract

The present invention provides a display device and a display method. [Solution] The sub-image generation module generates multiple sub-image signals based on the received image signal, the dithering module adjusts the gradation values ​​of target adjustment pixels in the multiple sub-image signals based on a blue noise mask and a gradation lookup table, and the control unit controls the image displayed by the image unit based on the gradation values ​​of the target adjustment pixels. According to the display device and display method of the present invention, it is possible to effectively generate more gradations and significantly improve the display quality of the display device.

Description

Technical Field

[0001] The present invention relates to an electronic device, and particularly to a display device and a display method.

Background Art

[0002] In the image display technology of a display device (for example, a projector or a liquid crystal display), since the distribution of the gradation of the image displayed by the display device is not uniform and more gradations cannot be effectively generated, a good image effect cannot be achieved.

[0003] The content of the "Background Art" paragraph is for assisting in understanding the content of the present invention, and the content described in the "Background Art" paragraph can include conventional technologies other than those grasped by those having ordinary knowledge in the technical field. Regarding the content described in the "Background Art" paragraph, what represents the problem to be solved by the content of the "Background Art" or one or more embodiments of the present invention is not already grasped or known by those having ordinary knowledge in the technical field before the filing of the present invention.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a display device and a display method that can effectively generate more gradations and significantly improve the display quality of the display device.

[0005] Other objects and advantages of the present invention will become more apparent from the technical features disclosed in the present invention.

Means for Solving the Problems

[0006] To achieve one, part or all, or any other of the above objectives, the present invention provides a display device comprising a sub-image generation module, a dithering module, a control unit, and an image unit, wherein the sub-image generation module generates a plurality of sub-image signals based on a received image signal; the dithering module is connected to the sub-image generation module, the dithering module includes a blue noise mask and a grayscale lookup table, the dithering module adjusts the grayscale values ​​of target adjustment pixels in the plurality of sub-image signals based on the blue noise mask and the grayscale lookup table; the control unit is connected to the dithering module and the image unit, and the control unit controls the image displayed by the image unit based on the grayscale values ​​of the target adjustment pixels.

[0007] The present invention further provides a display method for a display device, characterized in that it includes the steps of: a sub-image generation module generating a plurality of sub-image signals based on a received image signal; a dithering module adjusting the gradation values ​​of target adjustment pixels in the plurality of sub-image signals based on a blue noise mask and a gradation lookup table; and a control unit controlling the image displayed by the image unit based on the gradation values ​​of the target adjustment pixels. [Effects of the Invention]

[0008] As described above, in the embodiment of the present invention, the sub-image generation module generates a plurality of sub-image signals based on the received image signal, the dithering module adjusts the gradation values ​​of the target adjustment pixels in the plurality of sub-image signals based on the blue noise mask and the gradation lookup table, and the control unit controls the image displayed by the image unit based on the gradation values ​​of the target adjustment pixels. This makes it possible to effectively generate a larger number of gradations and significantly improve the display quality of the display device.

[0009] To make the above-mentioned features and advantages of the present invention clearer, embodiments will be described in detail below with reference to the drawings. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram of an example of a display device according to an embodiment of the present invention. [Figure 2] This is a schematic diagram of an example of a dithering module and control unit according to an embodiment of the present invention. [Figure 3A] Figures 3A and 3B are schematic diagrams of a sub-blue noise mask according to an embodiment of the present invention, in which sub-image signals corresponding to different time points are applied at different grayscale levels. [Figure 3B] Figures 3A and 3B are schematic diagrams of a sub-blue noise mask according to an embodiment of the present invention, in which sub-image signals corresponding to different time points are applied at different grayscale levels. [Figure 4] This is a schematic diagram of an example of a grayscale lookup table according to an embodiment of the present invention. [Figure 5] This is a schematic diagram of an example of a subblue noise mask corresponding to different time points and different frame rate conversion intensity values ​​according to an embodiment of the present invention. [Figure 6] This is a schematic diagram of an example of a lookup table for a blue noise mask according to an embodiment of the present invention. [Figure 7] This is a schematic diagram showing an example of the position of a target adjustment pixel in an image signal according to an embodiment of the present invention. [Figure 8] This is a flowchart illustrating an example of a display method for a display device according to an embodiment of the present invention. [Figure 9] Figures 9 and 10 are flowcharts illustrating a method for adjusting the grayscale value of a target adjustment pixel according to an embodiment of the present invention. [Figure 10] Figures 9 and 10 are flowcharts illustrating a method for adjusting the grayscale value of a target adjustment pixel according to an embodiment of the present invention. [Modes for carrying out the invention]

[0011] The above or other technical content, features and effects of the present invention will become apparent as shown in the detailed description of preferred embodiments with reference to the following drawings. Directional terms such as “up,” “down,” “left,” “right,” “front,” and “back” as used in the following embodiments are merely descriptive terms for reference to directions when referring to the drawings. For this reason, the present invention is not limited to those indicated by directional terms. Furthermore, the term “connection” as used in the following embodiments may mean any direct or indirect means of connection. Furthermore, the term “signal” may mean at least one current, voltage, charge, temperature, data, electromagnetic wave, or any one or more other signals.

[0012] Figure 1 is a schematic diagram of an example of a display device according to an embodiment of the present invention. As shown in Figure 1, the display device 100 may be, for example, a projection device (e.g., a projector) or a display (e.g., a liquid crystal display). The display device 100 may include a sub-image generation module 102, a dithering module 104, a control unit 106, and an image unit 108. The dithering module 104 is connected to the sub-image generation module 102. The control unit 106 is connected to the dithering module 104 and the image unit 108. The sub-image generation module 102 may generate n sub-image signals based on a received image signal (for example, the image signal is an image signal with an original resolution of 1080P and a frame rate of 60fps, but is not limited thereto). n is an integer of 1 or more (for example, it may be 2, 4, or 8). For example, one frame in the image signal may be divided into 2, 4, or 8 subframes to form a plurality of sub-image signals, which are then provided to the dithering module 104 for processing. In one embodiment, the sub-image generation module 102 may be a sub-image processing module, which may be used, for example, to divide one frame in an image signal (e.g., a 1080P / 30 or 60 fps image signal) into n (e.g., 4 or 8) identical subframes. In another embodiment, if the display device 100 is a projection device having a 4K (2160P) resolution, the sub-image generation module 102 may be, for example, an XPR 4P (eXpanded Pixel Resolution 4P) module, which may be used to divide one frame in an image signal (e.g., a 2160P / 60 fps image signal) into n (e.g., 4) different subframes. The sub-image generation module 102 may be connected to a signal input terminal (e.g., HDMI or DisplayPort) to acquire the image signal. In one embodiment, the sub-image generation module 102, the dithering module 104, and the control unit 106 may each include at least one processor.At least one processor may be a field-programmable logic gate array (FPGA), a microcontroller (MCU), or another device with computing power. The number of processors may be one or more. In one embodiment, at least two of the sub-image generation module 102, dithering module 104, and control unit 106 may be integrated into the same processor (e.g., a field-programmable logic gate array (FPGA)).

[0013] The dithering module 104 may include a blue noise mask and a gray level LUT. For example, the blue noise mask and the gray level LUT may be stored in a storage unit (not shown) within the dithering module 104 or in a storage unit (e.g., a storage medium not shown) connected to the dithering module 104. The dithering module 104 may adjust the gray level of the target adjustment pixel in the sub-image signal based on the blue noise mask and the gray level LUT. The control unit 106 may control the image displayed by the image unit 108 based on the gray level of the target adjustment pixel. In embodiments where the display device 100 is a projection device, the control unit 106 is a Digital Light Processing Controller (DLPC), and the image unit 108 is a light bulb. The light bulb controller may control the inversion of the micromirrors of the light bulb based on the gray level of the target adjustment pixel to convert the illumination beam into an image beam, and project the image beam outside the projection device via a projection lens. In embodiments where the display device 100 is a display, the control unit 106 may be a display controller (e.g., a liquid crystal controller), and the image unit 108 may be a display panel (e.g., a liquid crystal panel).

[0014] In this way, the sub-image generation module 102 generates multiple sub-image signals based on the image signal, and the dithering module 104 performs temporal dithering and spatial dithering based on the blue noise mask and gradation lookup table, thereby effectively generating more gradations and significantly improving the display quality of the display device 100.

[0015] In this embodiment, the dithering module 104 generates a plurality of sub-blue noise masks based on a blue noise mask, obtains the corresponding mask value in the blue noise mask based on the position of the target adjustment pixel in the corresponding sub-image signal, obtains the frame rate conversion intensity value (FRC intensity), spatial sub intensity value, first tone value, and second tone value corresponding to the original tone value of the target adjustment pixel based on a tone lookup table, performs a logical operation based on the mask value, frame rate conversion intensity value, and spatial sub intensity value, and adjusts the target adjustment pixel to the first tone value or the second tone value based on the calculation result. Here, the first tone value may be different from the second tone value (except when the original tone value is 0). The first tone value may also be less than or equal to the second tone value. If the first grayscale value is smaller than the second grayscale value, the first grayscale value may be used, for example, to display a pixel in a "dark" state, and the second grayscale value may be used, for example, to display a pixel in a "bright" state.

[0016] For example, as shown in Figure 2, the dithering module 104 may include a frame rate conversion module 202, a logical operation selection unit 204, and a spatial dithering module 206. The frame rate conversion module 202, the logical operation selection unit 204, and the spatial dithering module 206 may be integrated into the same processor, for example. For example, the frame rate conversion module 202 and the spatial dithering module 206 are each electrically connected to the logical operation selection unit 204. Taking n equal to 8 as an example, the sub-image generation module 102 may divide the image signal into eight sub-image signals, for example, so that the dithering module 104 performs temporal dithering and spatial dithering.

[0017] At an initial gradation level, the dithering module 104 may divide a blue noise mask into n (for example, 8) non-overlapping (initial) sub-blue noise masks. At least one sub-blue noise mask may be applied to a sub-image signal. At the initial gradation level, the number of (initial) sub-blue noise masks a to h is, for example, equal to the number of sub-image signals. FIG. 3A shows a schematic diagram in which sub-image signals SF1 to SF8 at eight time points such as t = 0 to 7 apply different sub-blue noise masks at different gradation levels. In one embodiment, the blue noise mask may be further divided into (non-initial) sub-blue noise masks of n gradation levels (the gradations from the lowest gradation to the highest gradation are equally divided into n) according to the gradation level so that sub-image signals SF1 to SF8 are applied at different gradation levels. For example, the n gradation levels are the first gradation level (initial gradation level 1 / n) to the nth gradation level (n / n), and the nth gradation level is the brightest. Each sub-blue noise mask may have, for example, 64 pixels. The blue noise mask may have, for example, 64×64 pixels according to the type of sub-blue noise mask and the gradation level. Taking n equal to 8 as an example, the sub-blue noise masks a to h corresponding to the first column with a gradation level of 1 / 8 are each obtained by performing temporal dithering on the sub-image signals SF1 to SF8 at the corresponding time points t = 0 to 7 using the blue noise mask. That is, the sub-blue noise masks a to h are each applied to n (for example, 8) sub-image signals SF1 to SF8. The ratio of the number of pixels in the "bright" state to the total number of pixels in each sub-blue noise mask a to h is 1 / 8, and there is no overlapping region of pixels in the "bright" state between the sub-blue noise masks a to h. That is, the sub-blue noise masks a to h are subsets that do not have a common set with each other.

[0018] The frame rate conversion module 202 may obtain (non-initial) sub-blue noise masks corresponding to other different gray levels (2 / 8 to 8 / 8) by performing a logical operation (e.g., OR operation) on the sub-blue noise masks a to h. When the gray level is a non-initial gray level of 2 / n to n / n, the number of sub-blue noise masks a to h applied at the corresponding time points t = 0 to 7 is plural (at least two), that is, the (non-initial) sub-blue noise mask is a combination of at least two of the plural sub-blue noise masks a to h. For example, in FIG. 3A, at t = 0, the mask (combination) of the second gray level 2 / 8 is a combination of the sub-blue noise masks a and b obtained by performing an OR operation on the sub-blue noise masks a and b. Thus, one or more sub-blue noise masks applied to the sub-image signals SF1 to SF8 at each time point t = 0 to 7 from the first gray level (initial gray level, 1 / n) to the nth gray level (n / n) are obtained. By superimposing the sub-image signals SF1 to SF8 at different time points t = 0 to 7, a uniform and complete image signal SUM without dot distribution is obtained.

[0019] If the gray levels that can be displayed by the image signal are further finely divided, for example, between the gray levels of 0 / 8 to 1 / 8, 1 / 8 to 2 / 8, 2 / 8 to 3 / 8, 3 / 8 to 4 / 8, 4 / 8 to 5 / 8, 5 / 8 to 6 / 8, 6 / 8 to 7 / 8, and 7 / 8 to 8 / 8, and more gray levels are further finely divided, the spatial dithering module 206 may adjust the ratio of the pixels in the "bright" display state in the sub-blue noise mask to further finely divide more gray levels.

[0020] Taking the sub-blue noise mask a in Figure 3A as an example, the proportion of pixels with a display state of "bright" in sub-blue noise mask a is 1 / 8. In sub-blue noise mask a, the proportion of pixels with a display state of "bright" may be reduced according to the spatial sub-intensity value s. Here, the spatial sub-intensity value s may be obtained, for example, according to the grayscale lookup table shown in Figure 4. Taking the input grayscale (original grayscale value of the target adjustment pixel) as an example, the corresponding first grayscale value g0 is equal to 0, the second grayscale value g1 is equal to 44, the frame rate conversion intensity value r is equal to 4, and the spatial sub-intensity value s is equal to 69. Here, the frame rate conversion intensity value r is related to the grayscale level, and the spatial sub-intensity value s is related to the number of pixels with a display state of "bright" in the spatial distribution. A higher value of s means that there are more pixels with a display state of "bright" in the spatial distribution, and the maximum value is when s = 256.

[0021] Assuming that the spatial sub-intensity value s of sub-blue noise mask a shown in Figure 3A is 256, reducing the proportion of pixels with a display state of "bright" according to the spatial sub-intensity value (e.g., s=64) yields sub-blue noise mask a' shown in Figure 3B, and the gradation corresponding to sub-blue noise mask a decreases from the initial gradation level 1 / n to (0 / n)+p (e.g., gradation level (0 / 8)+p). Here, p is equal to the spatial sub-intensity value divided by 256 and then by n, so when the spatial sub-intensity value is 64, p is equal to 1 / 32. Similarly, the gradation values ​​of the other sub-blue noise masks in Figure 3A can be adjusted in the same way to obtain the corresponding sub-blue noise masks in Figure 3B.

[0022] For example, the frame rate conversion module 202 may determine the corresponding sub-blue noise mask based on the correspondence between time point t and the frame rate conversion intensity value r shown in Figure 5, and may determine, for example, one (initial) sub-blue noise mask a-h, or a combination of multiple (initial) sub-blue noise masks a-h ((non-initial) sub-blue noise mask). In Figure 5, a-h represent the sub-blue noise masks a-h, respectively, and A-H are the results of performing an inverse operation on the sub-blue noise masks a-h (e.g., A=not(a), B=not(b), C=not(c), etc.). Therefore, each inverse mask (e.g., A=not(a)) may be performed as a logical combination (e.g., OR operation) of other sub-blue noise masks (e.g., b to h) defined as mutually exclusive subsets. In other words, in (initial) sub-blue noise mask a and (non-initial) sub-blue noise mask A (combinations of sub-blue noise masks b to h), pixels at the same position have opposite display states (for example, pixels at the same position are "bright" in sub-blue noise mask a and "dark" in sub-blue noise mask A).

[0023] The frame rate conversion module 202 may determine at least one sub-blue noise mask for the frame rate conversion intensity value r corresponding to the target adjustment pixel at the target time point t, according to the correspondence table shown in Figure 5. Here, each frame rate conversion intensity value r (e.g., r=1~8) corresponds to at least one of a plurality of sub-blue noise masks a~h at different time points t=0~7, and each sub-blue noise mask a~h has a corresponding sequence of mask values. The frame rate conversion module 202 may generate a first signal S1 by determining whether the mask value of the target adjustment pixel falls within the sequence of mask values ​​of the sub-blue noise mask corresponding to the frame rate conversion intensity value. The first signal S1 indicates whether the mask value of the target adjustment pixel falls within the sequence of mask values ​​of at least one sub-blue noise mask corresponding to the target time point t and frame rate conversion intensity value r. The sequence of mask values ​​includes multiple numerical values. The multiple numerical values ​​in the sequence of mask values ​​for each blue noise mask a~h are subsets that do not have any common set with each other. The numbers may be consecutive integers or discontinuous integers, and the numbers may or may not have a pattern.

[0024] For example, as shown in Figure 4, the frame rate conversion module 202 may use a grayscale lookup table to obtain a frame rate conversion intensity value r corresponding to the input grayscale. Assuming that the frame rate conversion intensity value r corresponding to the input grayscale (the original grayscale value of the target adjustment pixel) is equal to 2, and the combination of sub-blue noise masks corresponding to the target time t=1 and frame rate conversion intensity value r=2 are sub-blue noise masks c and d, the frame rate conversion module 202 may generate a first signal S1 based on sub-blue noise masks c and d. The frame rate conversion module 202 may determine whether the mask value of the target adjustment pixel falls within the sequence of mask values ​​of sub-blue noise mask c or d. Here, the mask value of the target adjustment pixel may be obtained, for example, by a dithering module 104 (e.g., frame rate conversion module 202 and / or spatial dithering module 206) according to the blue noise mask lookup table shown in Figure 6. The blue noise mask has 64 × 64 pixels, each pixel having a corresponding mask value. As shown in Figure 6, the mask value of the target adjustment pixel may be obtained from the mask via a LUT.

[0025] The dithering module 104 may process the image signal (including sub-image signals SF1 to SF8) using a blue noise mask. Assuming the image signal is a 1920 × 1080 resolution image as shown in Figure 7, the blue noise mask BLM1 contains 64 × 64 pixels as shown in Figure 6, so multiple blue noise masks BLM1 are applied to the processing of the original image signal. In one embodiment, the multiple blue noise masks BLM1 may be the same or different blue noise masks, and a specific blue noise mask may be applied depending on a specific time. The frame rate conversion module 202 may obtain the corresponding mask value in the blue noise mask BLM1 based on the position of the target adjustment pixel in the corresponding sub-image signals SF1 to SF8. For example, in Figure 7, the coordinate position (x, y) of the target adjustment pixel P1 is (96, 32), and the remainder when the x-axis coordinate position and the y-axis coordinate position are each divided by 64 is the coordinate position (32, 32) of the target adjustment pixel P1 in the corresponding blue noise mask BLM1. Based on this coordinate position (32,32), the mask value corresponding to the coordinate position (32,32), retrieved from the blue noise mask lookup table in Figure 6, is 132. In this way, the frame rate conversion module 202 can obtain the corresponding blue noise mask value for each pixel in the sub-image signals SF1 to SF8. The range of the mask value is, for example, 0 to 255, and the mask value is related to making the display state of the pixel "bright" or "dark".

[0026] The frame rate conversion module 202 may generate a first signal S1 based on the searched mask value and at least one sub-blue noise mask a-h corresponding to the target adjustment pixel P1. For example, the sequence of mask values ​​for each blue noise mask a-h has a range of mask values ​​(e.g., including consecutive integers). Sub-blue noise mask a is designed to make pixels whose mask value sequence falls between 0 and 32 appear "bright" and otherwise appear "dark," while sub-blue noise masks b, c, d, e, f, g, h are designed to make pixels whose mask value sequence falls between 33-64, 65-96, 97-128, 129-160, 161-192, 193-224, and 225-256 appear "bright" and otherwise appear "dark." For example, at the above time point t=1, the (non-initial) sub-blue noise mask corresponding to the frame rate conversion intensity value r=2 is a combination of sub-blue noise masks c and d, and the first signal S1 indicates that the mask value 132 of the target adjustment pixel P1 is not included in the sequence of mask values ​​of sub-blue noise masks c and d. The frame rate conversion module 202 may generate the first signal S1 by performing an OR operation on the output result of whether or not the mask value of the target adjustment pixel P1 is included in the sequence of mask values ​​of sub-blue noise masks c and d. For example, the result in which the mask value of the target adjustment pixel P1 is included in the sequence of mask values ​​of the sub-blue noise mask is set to a bit value of "1", and the output result in which the mask value of the target adjustment pixel P1 is not included in the sequence of mask values ​​of the sub-blue noise mask is set to a bit value of "0", and an OR operation is performed to generate the first signal S1. Assuming that when performing an OR operation, if the mask value of the target adjustment pixel P1 falls within the sequence of mask values ​​of either sub-blue noise mask c or d, the display state of the target adjustment pixel is set to "bright," and otherwise it is set to "dark," in this embodiment, since the mask value 132 of the target adjustment pixel does not fall within the sequence of mask values ​​of sub-blue noise mask c or d, the first signal S1 indicates that the display state of the target adjustment pixel is "dark," that is, the output result of the first signal S1 is a bit value of "0."

[0027] Similarly, when the input grayscale is 18, as described above, the corresponding frame rate conversion intensity value r is equal to 4, and according to the correspondence table shown in Figure 5, the corresponding at least one sub-blue noise mask (non-initial sub-blue noise mask) at time t=1 is a combination of sub-blue noise masks e, f, g, and h, and the frame rate conversion module 202 generates a first signal S1 based on the sub-blue noise masks e, f, g, and h. The frame rate conversion module 202 performs an OR operation on the result of whether the mask value of the target adjustment pixel P1 falls within the sequence of mask values ​​of the sub-blue noise masks e, f, g, and h. Here, if the mask value of the target adjustment pixel P1 falls within the sequence of mask values ​​of any of the sub-blue noise masks e, f, g, and h, the display state of the target adjustment pixel P1 is set to "bright", and if the mask value of the target adjustment pixel P1 does not fall within the sequence of mask values ​​of any of the sub-blue noise masks e, f, g, and h, the display state of the target adjustment pixel is set to "dark". Accordingly, the first signal S1 indicates whether the display state of the target adjustment pixel P1 is "bright" or "dark". For example, if the mask value 132 of the target adjustment pixel P1 falls within the sequence of mask values ​​(129-160) of the sub-blue noise mask e, but not within the sequence of mask values ​​of the sub-blue noise masks f, g, and h, the display state of the target adjustment pixel P1 is set to "bright". Accordingly, the first signal S1 indicates that the display state of the target adjustment pixel P1 is "bright", that is, the output result of the first signal S1 is a bit value of "1".

[0028] The spatial dithering module 206 may obtain a spatial sub-intensity value s according to a grayscale lookup table and obtain a sequence of mask values ​​for the sub-blue noise mask (any of a to h) corresponding to the target adjustment pixel P1 according to the blue noise mask. The spatial dithering module 206 calculates a numerical interval according to the sequence of mask values ​​for the sub-blue noise mask corresponding to the target adjustment pixel P1 and the spatial sub-intensity value s. Here, the sequence of mask values ​​for the sub-blue noise mask corresponding to the target adjustment pixel P1 includes the mask value of the target adjustment pixel P1. The spatial dithering module 206 may obtain a mask value corresponding to the target adjustment pixel P1 according to a blue noise mask lookup table and obtain a sequence of mask values ​​for the corresponding sub-blue noise mask based on the mask value corresponding to the target adjustment pixel P1. In this embodiment, the sequence of mask values ​​is, for example, a range of mask values ​​having consecutive integers, and the maximum value of the numerical interval may be calculated, for example, according to the following formula (1).

[0029] R1 = V1 + (256 / n) * (s / 256) (1) (Alternatively, it may be expressed as R1 = V1 + (s / n)) R1 is the maximum value of the numerical interval, V1 is the minimum value of the sequence of mask values ​​of a sub-blue noise mask (any of a to h) whose sequence of mask values ​​includes the mask value of the target adjustment pixel P1, and is also the minimum value of the numerical interval, n is the number of sub-image signals, and s is the spatial sub-intensity value. For example, if the mask value of the target adjustment pixel P1 is v=132, the corresponding spatial sub-intensity value is s=69, and the sequence of mask values ​​of the corresponding sub-blue noise mask e is 129~160, then the spatial dithering module 206 may calculate, according to equation (1), that the maximum value R1 of the numerical interval is 137.625, and the numerical interval is, for example, 129~137.625. The spatial dithering module 206 may also determine whether the mask value (132) of the target adjustment pixel P1 falls within the numerical interval and generate a second signal S2. The second signal S2 indicates whether the mask value of the target adjustment pixel P1 falls within the numerical interval. The numerical interval is greater than or equal to V1 and less than or equal to R1. If the mask value of the target adjustment pixel P1 falls within the numerical interval V1 to R1, the second signal S2 indicates that the display state of the target adjustment pixel is "bright," and that is, the output result of the second signal S2 is a bit value of "1." If the mask value of the target adjustment pixel does not fall within the numerical interval, the second signal S2 indicates that the display state of the target adjustment pixel is "dark," and that is, the output result of the second signal S2 is a bit value of "0."

[0030] In other embodiments, the spatial dithering module 206 may determine the numerical interval based on V1 and (256 / n)*(s / 256). Here, the maximum value R1 of the numerical interval is the (256 / n)*(s / 256)th number (which may be expressed as the s / nth number) in the sequence of mask values ​​of the sub-blue noise mask (any of a to h) corresponding to the target adjustment pixel P1. The minimum value of the numerical interval is the minimum value of the sequence of mask values ​​of the sub-blue noise mask (any of a to h) that includes the mask value of the target adjustment pixel P1. For example, assuming that n is equal to 8 and s is equal to 128, this indicates that the numbers from V1 (minimum value) to the (256 / n)*(s / 256)th (e.g., the 16th) in the sequence of mask values ​​of the sub-blue noise mask (any of a to h) corresponding to the target adjustment pixel P1 correspond to a "bright" display state, and the remaining numbers correspond to a "dark" display state.

[0031] The logical operation selection unit 204 may obtain a first grayscale value g0 and a second grayscale value g1 according to a grayscale lookup table. The logical operation selection unit 204 may perform a logical operation based on a first signal S1 from the frame rate conversion module 202 and a second signal S2 from the spatial dithering module 206, and adjust the grayscale value of the target adjustment pixel P1 to the first grayscale value g0 or the second grayscale value g1 based on the calculation result. The logical operation may be, for example, an AND operation. For example, if at least one of the first signal S1 and the second signal S2 indicates that the display state of the target adjustment pixel is "dark", that is, if the output result of at least one of the first signal S1 and the second signal S2 is a bit value "0", the logical operation selection unit 204 may be configured to adjust the (original) grayscale value (input grayscale) of the target adjustment pixel P1 to the first grayscale value g0. If both the first signal S1 and the second signal S2 indicate that the display state of the target adjustment pixel is "bright," that is, if the output results of the first signal S1 and the second signal S2 are bit values ​​of "1," the logical operation selection unit 204 adjusts the (original) gradation value (input gradation) of the target adjustment pixel P1 to the second gradation value g1. The control unit 106 may control the image unit 108 to display the target adjustment pixel as either the first gradation value g0 or the second gradation value g1, depending on the adjustment result by the logical operation selection unit 204.

[0032] Similarly, the dithering module 104 may adjust the gradation values ​​for pixels at different positions in each sub-image signal. As shown in the gradation lookup table in Figure 4, with a few exceptions, most of the first gradation value g0 and the second gradation value g1 are different from the original gradation value (input gradation). For example, if the input gradation is 0, 44, or 61, at least one of the first gradation value g0 and the second gradation value g1 is equal to the input gradation. The dithering module 104 according to this embodiment can generate more gradations and improve the display quality of the display device 100 by performing the above logical operations.

[0033] The above embodiment takes the example of dividing an image signal into n=8 sub-image signals SF1~SF8 in order to perform temporal and spatial dithering. In other embodiments, in order to achieve better display effects, the bit depth may be optimized by dividing the image signal into a corresponding number of sub-image signals (e.g., 2, 4, but not limited to these) depending on the different resolution and frame rate. For example, taking a projection device (display device 100) with an original resolution of 1080p and a screen refresh rate of 240Hz as an example, if the resolution of the image signal is 1080p and the frame rate is 30fps, one frame (image signal) may be divided into 8 subframes (sub-image signals). In this case, the total frame rate will be 240fps. Similarly, if the resolution of the image signal is 1080p and the frame rate is 60fps, one frame (image signal) may be divided into 4 subframes (sub-image signals). If the resolution of the image signal is 4K, the frame rate is 60fps, and the image signal is relatively static, one frame may be divided into two subframes. The contents of the two subframes are essentially the same or completely identical, and the two 4K, 60fps subframes may be merged into one 4K, 30fps frame.

[0034] Figure 8 is a flowchart of an example of a display method for a display device according to an embodiment of the present invention. According to the above embodiment, the display method of the display device 100 may include at least the following steps. First, the sub-image generation module 102 generates a plurality of sub-image signals based on the received image signal (step S802). Next, the dithering module 104 adjusts the gradation value of the target adjustment pixel in the sub-image signal based on the blue noise mask and the gradation lookup table (step S804). Finally, the control unit 106 controls the image displayed by the image unit 108 based on the gradation value of the target adjustment pixel P1 (step S806). The display device 100 may be, for example, a projection device, the control unit 106 may be, for example, a light bulb controller, the image unit 108 may be, for example, a light bulb, and the light bulb controller may control the inversion of the micromirror of the light bulb based on the gradation value (corresponding control signal) of the target adjustment pixel P1.

[0035] In this embodiment, step S804 may include steps S902 to S910, as shown in Figure 9. First, the dithering module 104 generates a plurality of sub-blue noise masks a to h based on the blue noise mask (step S902). Next, the dithering module 104 obtains the corresponding mask value in the blue noise mask based on the position of the target adjustment pixel P1 in the corresponding sub-image signal (step S904). Next, the dithering module 104 obtains the frame rate conversion intensity value r, spatial sub-intensity value s, first gradation value g0, and second gradation value g1 of the original gradation value corresponding to the target adjustment pixel P1 based on the gradation lookup table (step S906). Next, the dithering module 104 performs a logical operation based on the mask value, frame rate conversion intensity value, and spatial sub-intensity value (step S908). Here, the logical operation may be, for example, an AND operation. Finally, based on the calculation result, the target adjustment pixel P1 is adjusted to the first or second gradation value (step S910). Here, the first gradation value g0 may be different from the second gradation value g1.

[0036] In this embodiment, the frame rate conversion intensity value r corresponds to at least one of a plurality of sub-blue noise masks a to h, and each sub-blue noise mask a to h has a corresponding sequence of mask values. The method for adjusting the gradation value of the target adjustment pixel P1 is as shown in Figure 10, by performing steps S1002 to S1012 using the dithering module 104. First, at least one sub-blue noise mask corresponding to the frame rate conversion intensity value r of the target adjustment pixel P1 is determined at the target time t (step S1002). Next, it is determined whether the mask value of the target adjustment pixel P1 falls within the mask value range (sequence of mask values) of at least one sub-blue noise mask corresponding to the frame rate conversion intensity value r, and a first signal S1 is generated (step S1004). Here, the first signal S1 indicates whether the mask value of the target adjustment pixel P1 falls within the mask value range (sequence of mask values) of at least one sub-blue noise mask corresponding to the target time t and the frame rate conversion intensity value r. Next, a numerical interval is calculated based on the mask value range (sequence of mask values) and spatial sub-intensity value s of the sub-blue noise mask corresponding to the target adjustment pixel P1 (step S1006). Here, the mask value range (sequence of mask values) of the sub-blue noise mask corresponding to the target adjustment pixel P1 includes the mask value of the target adjustment pixel P1. The calculation method for the numerical interval may be as shown in equation (1) above, so the explanation is omitted here. Next, a second signal S2 is generated by determining whether or not the mask value of the target adjustment pixel P1 falls within the numerical interval (step S1008). Here, the second signal S2 indicates whether or not the mask value of the target adjustment pixel P1 falls within the numerical interval. Next, in one embodiment, as shown in Figure 2, the steps of the frame rate conversion module 202 generating the first signal S1 (steps S1002 and S1004) and the spatial dithering module 206 generating the second signal S2 (steps S1006 and S1008) may be performed simultaneously. Next, a logical operation is performed based on the first signal S1 and the second signal S2 (step S1010), and based on the calculation result, the gradation value of the target adjustment pixel P1 is adjusted to the first gradation value or the second gradation value (step S1012).

[0037] Based on the above, in the present invention, the sub-image generation module generates multiple sub-image signals based on the received image signal, the dithering module adjusts the gradation values ​​of target adjustment pixels in the multiple sub-image signals based on the blue noise mask and gradation lookup table, and the control unit controls the image displayed by the image unit based on the gradation values ​​of the target adjustment pixels. This makes it possible to effectively generate more gradations and significantly improve the display quality of the display device.

[0038] The above are merely preferred embodiments of the present invention, and the scope of implementation of the present invention is not limited thereto. Any modifications and modifications are possible by those skilled in the art based on the claims and specification of the present invention, and the scope of protection of the present invention is based on the claims. Furthermore, none of the embodiments or claims of the present invention necessarily have to realize all of the purposes, advantages, or features disclosed by the present invention. In addition, the abstract and the title of the invention are merely for the purpose of assisting in the search of patent documents and do not limit the scope of rights of the present invention. Furthermore, terms such as "first," "second," etc. in this specification or the claims are merely for naming elements or distinguishing different embodiments or scopes, and do not limit the upper or lower limit of the number of components.

Claims

1. A display device comprising a sub-image generation module, a dithering module, a control unit, and an image unit, The sub-image generation module generates multiple sub-image signals based on the received image signal, The dithering module is connected to the sub-image generation module, and the dithering module includes a blue noise mask and a tone lookup table, and the dithering module adjusts the tone values ​​of target adjustment pixels in the plurality of sub-image signals based on the blue noise mask and the tone lookup table. The control unit is connected to the dithering module and the image unit, and the control unit controls the image displayed by the image unit based on the grayscale value of the target adjustment pixel.

2. The control unit is a light bulb controller, The image portion is a light bulb, The display device according to claim 1, characterized in that the light bulb controller controls the light bulb based on the grayscale value of the target adjustment pixel.

3. The control unit is a display controller, The aforementioned image section is a display panel, The display device according to claim 1, characterized in that the display controller controls the display panel based on the grayscale value of the target adjustment pixel.

4. The aforementioned dithering module is Based on the aforementioned blue noise mask, multiple sub-blue noise masks are generated. Based on the position of the target adjustment pixel in the corresponding sub-image signal, the corresponding mask value in the blue noise mask is obtained. Based on the aforementioned grayscale lookup table, the frame rate conversion intensity value, spatial sub-intensity value, first grayscale value, and second grayscale value corresponding to the original grayscale value of the target adjustment pixel are obtained. Based on the mask value, the frame rate conversion intensity value, and the spatial sub-intensity value, a logical operation is performed. The display device according to claim 1, characterized in that the target adjustment pixel is adjusted to the first or second grayscale value based on the calculation result.

5. The display device according to claim 4, characterized in that the first grayscale value is different from the second grayscale value.

6. The dithering module includes a frame rate conversion module, a spatial dithering module, and a logical operation selection unit. The frame rate conversion module and the spatial dithering module are each electrically connected to the logical operation selection unit. The frame rate conversion intensity value corresponds to at least one of the plurality of subblue noise masks, and each of the plurality of subblue noise masks has a corresponding sequence of mask values. The frame rate conversion module determines at least one sub-blue noise mask corresponding to the frame rate conversion intensity value of the target adjustment pixel at the target time point, The frame rate conversion module determines whether the mask value of the target adjustment pixel falls within a sequence of mask values ​​of at least one sub-blue noise mask corresponding to the frame rate conversion intensity value, and generates a first signal. The first signal indicates whether the mask value of the target adjustment pixel falls within a sequence of mask values ​​of at least one subblue noise mask corresponding to the target time and the frame rate conversion intensity value. The spatial dithering module calculates a numerical interval based on the sequence of mask values ​​of the sub-blue noise mask corresponding to the target adjustment pixel and the spatial sub-intensity value, The sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel includes the mask value of the target adjustment pixel. The spatial dithering module determines whether the mask value of the target adjustment pixel falls within the numerical interval and generates a second signal. The second signal indicates whether the mask value of the target adjustment pixel falls within the numerical interval. The display device according to claim 4, characterized in that the logical operation selection unit performs the logical operation based on the first signal from the frame rate conversion module and the second signal from the spatial dithering module, and adjusts the gradation value of the target adjustment pixel to the first gradation value or the second gradation value based on the calculation result.

7. The maximum value in the aforementioned numerical interval is given by equation (1). R1=V1+(256 / n)*(s / 256) (1) It is calculated according to the following: The display device according to claim 6, wherein R1 is the maximum value of the numerical interval, V1 is the minimum value of the sequence of mask values ​​of the sub-blue noise mask corresponding to the target adjustment pixel, n is the number of the plurality of sub-image signals, and s is the spatial sub-intensity value, wherein V1 is the minimum value of the numerical interval.

8. The maximum value in the aforementioned numerical interval is the (256 / n) * (s / 256)th number in the sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel. The display device according to claim 6, characterized in that the minimum value of the numerical interval is the minimum value of the sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel.

9. The dithering module generates a corresponding number of subblue noise masks based on the plurality of sub-image signals, The display device according to claim 4, characterized in that the number of the plurality of sub-image signals is n, where n is an integer of 1 or more.

10. A display method for a display device, The sub-image generation module generates multiple sub-image signals based on the received image signal, The dithering module adjusts the tonal values ​​of target adjustment pixels in the plurality of sub-image signals based on a blue noise mask and a tonal lookup table. A display method for a display device, characterized by comprising the step of a control unit controlling an image displayed by an image unit based on the grayscale value of the target adjustment pixel.

11. The control unit is a light bulb controller, The image portion is a light bulb, The display method for the display device according to claim 10, characterized in that the light bulb controller controls the light bulb based on the grayscale value of the target adjustment pixel.

12. The step of the dithering module adjusting the grayscale value of the target adjustment pixel in the plurality of sub-image signals based on the blue noise mask and the grayscale lookup table is: The steps include generating a plurality of sub-blue noise masks based on the blue noise mask, A step of obtaining a corresponding mask value in the blue noise mask based on the position of the target adjustment pixel in the corresponding sub-image signal, The steps include obtaining a frame rate conversion intensity value, a spatial sub-intensity value, a first tone value, and a second tone value corresponding to the original tone value of the target adjustment pixel based on the tone lookup table, The steps include performing a logical operation based on the mask value, the frame rate conversion intensity value, and the spatial sub-intensity value, A display method for a display device according to claim 10, comprising the step of adjusting the target adjustment pixel to the first or second grayscale value based on the calculation result, wherein the first grayscale value is different from the second grayscale value.

13. The frame rate conversion intensity value corresponds to at least one of the plurality of subblue noise masks, and each of the plurality of subblue noise masks has a corresponding sequence of mask values. The aforementioned display method is, The dithering module includes the step of determining at least one subblue noise mask corresponding to the frame rate conversion intensity value of the target adjustment pixel at a target time point, The dithering module generates a first signal by determining whether the mask value of the target adjustment pixel falls within a sequence of mask values ​​of at least one sub-blue noise mask corresponding to the frame rate conversion intensity value, wherein the first signal indicates whether the mask value of the target adjustment pixel falls within a sequence of mask values ​​of at least one sub-blue noise mask corresponding to the target time and the frame rate conversion intensity value. The dithering module calculates a numerical interval based on a sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel and the spatial sub-intensity value, wherein the sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel includes the mask value of the target adjustment pixel. The dithering module determines whether the mask value of the target adjustment pixel falls within the numerical interval and generates a second signal, wherein the second signal indicates whether the mask value of the target adjustment pixel falls within the numerical interval. The dithering module performs the logical operation based on the first signal and the second signal, The display method for a display device according to claim 12, further comprising the step of adjusting the gradation value of the target adjustment pixel to the first gradation value or the second gradation value based on the calculation result.

14. The maximum value in the aforementioned numerical interval is given by equation (1). R1=V1+(256 / n)*(s / 256) (1) It is calculated according to the following: The display method for a display device according to claim 13, wherein R1 is the maximum value of the numerical interval, V1 is the minimum value of the sequence of mask values ​​of the sub-blue noise mask corresponding to the target adjustment pixel, n is the number of the plurality of sub-image signals, and s is the spatial sub-intensity value, wherein V1 is the minimum value of the numerical interval.

15. The maximum value in the aforementioned numerical interval is the (256 / n) * (s / 256)th number in the sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel. The display method for the display device according to claim 13, characterized in that the minimum value of the numerical interval is the minimum value of the sequence of mask values ​​of the subblue noise mask corresponding to the target adjustment pixel.

Images