A method for controlling gray scale display of an LED screen frame by frame

Abstract

The application discloses a kind of led screen frame-by-frame control gray scale display method, comprising: setting gray scale, gray scale corresponds to the number of subframe;Memory allocation, according to gray scale value and resolution, corresponding memory space is applied as buffer for saving subsequent subframe data needed to be decomposed;Gray scale graphic data is sequentially decomposed to each subframe according to each pixel point;Subframe buffer write, read data in subframe buffer is sequentially brushed into display, and subframe buffer is read again after reading is finished, and dynamic display of screen is achieved through dynamic writing of data. Through software frame-by-frame control of the brightness of all LED lamps of each frame, the problem of non-linear relationship and poor low gray scale dimming effect in traditional hardware PWM control is avoided. Compared with the prior art, the unique feature of this technology is that it can achieve gray scale effect without adding extra hardware, and the gray scale control is more precise and stable.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more specifically to a method for controlling grayscale display on an LED screen frame by frame. Background Technology

[0002] LED monochrome screens typically display only one color, such as white or blue. To achieve a grayscale effect, that is, to display images or text at different grayscale levels, the commonly used technique and process is to control the brightness of the LEDs using PWM technology.

[0003] Existing PWM control methods suffer from defects such as unstable brightness and obvious mosaic effect. The technical essence of these defects is the nonlinear relationship in PWM control of LED brightness and the poor dimming effect under low grayscale, as well as the high hardware cost and complexity. Summary of the Invention

[0004] To address the shortcomings of existing PWM control methods for grayscale display on LED monochrome screens, such as unstable brightness, noticeable mosaic effect, and high hardware costs, this invention provides a frame-by-frame grayscale display control method for LED screens. This method controls the brightness of all LEDs in each frame via software, avoiding the non-linear relationships and poor low-grayscale dimming effects inherent in traditional hardware PWM control. Compared to traditional technologies, this unique feature is that it can achieve grayscale effects without adding extra hardware, and provides more precise and stable grayscale control.

[0005] The technical solution adopted in this application is as follows:

[0006] A method for frame-by-frame control of grayscale display on an LED screen includes:

[0007] Set the grayscale levels, and the grayscale levels correspond to the number of subframes;

[0008] Allocate memory: Based on the grayscale value and resolution, request corresponding memory space as a buffer to store the subframe data that needs to be decomposed later.

[0009] The grayscale image data is decomposed into each subframe in order of each pixel.

[0010] Subframe buffer writing and reading involves sequentially flushing the data in the subframe buffer to the display. Once the subframe buffer reading is finished, it is read again. Through dynamic data writing, dynamic display on the screen is achieved.

[0011] In some embodiments, the setting of grayscale levels, where each grayscale level corresponds to a subframe number and the pixel grayscale value corresponds to a percentage of the subframe number, includes:

[0012] If the image needs to display a grayscale level N, the number of preprocessed subframe buffers that need to be updated is N-1.

[0013] In some embodiments, the memory allocation involves requesting corresponding memory space as a buffer based on grayscale values ​​and resolutions to store subframe data that needs to be decomposed subsequently; including:

[0014] The screen resolution is A*B. K bytes of memory are dynamically allocated for the storage of the preprocessed subframe image, K = (N-1)*A*B / 8. Each frame buffer can correspond to the position of the dot matrix LED in the LED monochrome screen. i represents the data of the first frame. The start and end positions of each subframe are SE(i) = (i-1)*A*B / 8.

[0015] In some embodiments, the step of decomposing grayscale image data into each subframe in order of each pixel includes:

[0016] The gray values ​​G of the original grayscale image data pixel (x,y) coordinates are obtained sequentially. These gray values ​​are based on the current grayscale level. g is less than N. The offset (x,y) start and end positions are calculated.

[0017] Decompose the grayscale values ​​into subframes in sequence, calculate the grayscale level of the current pixel g = G / N, and determine that the coordinates of the corresponding positions in g-1 subframes need to be set to 1, i.e., val[se(j)+offset(x,y)] = 1,j = 1,2,3,g; where val is the value of the corresponding coordinate in dynamic memory, that is, the grayscale value is set to the corresponding coordinate of each subframe.

[0018] The beneficial effects of this invention are:

[0019] Improve display clarity and brightness: This technology enables frame-by-frame grayscale control of each pixel, thereby improving the clarity and brightness of the display.

[0020] Reduced power consumption and cost: Compared with traditional PWM control methods, the technical solution of this patent can greatly reduce power consumption and cost, thereby improving the lifespan and economic benefits of the display screen.

[0021] Improved response speed and stability: The technical solution of this patent adopts software control, which can achieve precise control of each pixel, thereby improving the response speed and stability of the display screen.

[0022] Wider applicability: The technical solution of this patent can be applied to various types of binary monochrome displays, and has strong versatility and scalability. Attached Figure Description

[0023] Figure 1 A schematic diagram of a grayscale image decomposed into 3 subframes in 4 levels;

[0024] Figure 2 This is a schematic diagram illustrating the grayscale effect of writing three subframes generated with 4 levels of grayscale to the display screen frame by frame. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0026] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0029] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or display that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or display.

[0030] The following will combine Figure 1-2 The embodiments of this application will be described in detail below. It is worth noting that the following embodiments are only used to explain this application and do not constitute a limitation on this application.

[0031] Step 1: Set the grayscale level N to be displayed in the image, and the number of preprocessed subframe buffers to be updated is N-1.

[0032] Step 2: Allocate memory. The screen resolution is A*B. Allocate K bytes of dynamic memory for the preprocessed subframe image as storage, K = (N-1)*A*B / 8.

[0033] Step 3: Frame data positioning. Each frame buffer bit can correspond to the position of the LED dot matrix in the monochrome LED screen. i represents the first frame data. The start and end positions of each subframe are SE(i) = (i-1)*A*B / 8.

[0034] Step 4: Decompose the original data. Decompose the grayscale image data into each subframe according to each pixel. The decomposition steps are as follows:

[0035] Obtain the gray value G of the original grayscale image data pixel (x,y) coordinates in sequence. This gray value is based on the current grayscale level. g needs to be less than N. Calculate the offset (x,y) start and end positions.

[0036] The grayscale values ​​are sequentially decomposed into subframes. The grayscale level of the current pixel is calculated as g = G / N. It is determined that the coordinates of the corresponding positions in g-1 subframes need to be set to 1.

[0037] Subframe 0val[se(1)+offset(x,y)]=1

[0038] Subframe 1val[se(2)+offset(x,y)]=1

[0039] Subframe 2val[se(3)+offset(x,y)]=1

[0040] …………

[0041] Subframe g-1val[se(g)+offset(x,y)]=1

[0042] Where val is the value of the corresponding coordinate in dynamic memory, that is, the grayscale value is set to the coordinate corresponding to each subframe.

[0043] Step 5: Write frame data to the screen. Refresh the subframes to the display frame by frame according to the rules. Refresh the K bytes of data storing all subframes in order of order N. Write A*B / 8 data to the display screen from position SE(i) each time.

[0044] Step 6: Dynamic display. After writing all the subframe data, in order to achieve the dynamic display effect, the frame buffer data needs to be rewritten and continuously written to the display screen. According to the proportion of grayscale data in the number of subframes, the visual persistence effect achieves grayscale display.

[0045] The technical solution of this application achieves high-quality display on a binary monochrome display screen by finely controlling each frame of the image. This improves the detail and gradation effects within a limited color range, while avoiding pixel distortion and color distortion problems that occur when image data is over-compressed. Through this technique, the solution successfully overcomes the problem of low grayscale quality in traditional monochrome displays, achieving a higher quality image display effect.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for frame-by-frame control of grayscale display on an LED screen, characterized in that, include: Set the grayscale levels, and the grayscale levels correspond to the number of subframes; Allocate memory: Based on the grayscale value and resolution, request corresponding memory space as a buffer to store the subframe data that needs to be decomposed later. The grayscale image data is decomposed into each subframe in order of each pixel. Subframe buffer writing and reading involves sequentially flushing the data in the subframe buffer to the display, and then rereading the subframe buffer after it finishes reading. Through dynamic data writing, dynamic display on the screen is achieved. The setting of grayscale levels, where each grayscale level corresponds to a subframe number, and each pixel grayscale value corresponds to a percentage of the subframe number; includes: If the image needs to display a grayscale level N, the number of preprocessed subframe buffers that need to be updated is N-1. The memory allocation, based on grayscale values ​​and resolution, requests corresponding memory space as a buffer to store subsequent subframe data that needs to be decomposed; including: The screen resolution is A*B, and K bytes of memory are dynamically allocated for storage of the preprocessed subframe images. Each frame buffer corresponds to the position of the LED dot matrix in the monochrome LED screen, where i represents the i-th frame of data and the start and end positions of each subframe. ; The step of decomposing grayscale image data into each subframe sequentially according to each pixel includes: Obtain the grayscale value G of the (x, y) coordinate points of the original grayscale image data pixels in sequence. This grayscale value is based on the current grayscale level, and g is less than N. Calculate the start and end positions of the offset. ; The grayscale values ​​are sequentially decomposed into subframes. The grayscale level of the current pixel is calculated as g = G / N. The coordinates of the corresponding positions in the g-1 subframes are determined to be set to 1. j=1,2,3…g; where val is the value of the corresponding coordinate in dynamic memory, that is, the grayscale value is set to the coordinate corresponding to each subframe.

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