A method and apparatus for enhancing the color temperature of grayscale medical images

Abstract

This invention discloses a method and apparatus for enhancing the color temperature of grayscale medical images in the field of medical display devices, aiming to solve the technical problem that medical images displayed by existing display devices are not clearly distinguishable to the human eye. It includes: acquiring display feature data of a liquid crystal display (LCD); calculating correction values ​​based on the display feature data; establishing a feature correction lookup table for the LCD based on the correction values; inputting and parsing a grayscale medical image to obtain RGB input values; converting the RGB input values ​​into RGB output values ​​according to the feature correction lookup table, and generating a corresponding output image for display on the LCD. By using the method of this invention, grayscale medical images can be clearly displayed on the LCD, facilitating human identification and diagnosis.

Description

Technical Field

[0001] This invention relates to a method and apparatus for enhancing the color temperature of grayscale medical images, belonging to the technical field of medical display equipment. Background Technology

[0002] With the development of mobile internet, and considering the trend of globalization and uncontrollable factors such as the pandemic, severe weather, and geological disasters, medical workers hope to have more convenient office equipment so that they can view patients' medical imaging test data at home, on the road, or even in isolation facilities.

[0003] Compared to ordinary display devices, medical professional display equipment not only has higher resolution, higher brightness and higher contrast, but also has a grayscale display brightness response curve correction function that conforms to the DICOM (Digital Imaging and Communications in Medicine) standard (hereinafter referred to as DICOM curve).

[0004] Grayscale refers to the number of brightness levels that a single pixel in a display device can display while maintaining a constant backlight brightness. The most common LCD monitors typically display 256 grayscale levels, named from 0 to 255. The relationship between grayscale and brightness is called the grayscale luminance response curve. The brightness of grayscale 255 is called the white point luminance, which is generally limited by the maximum brightness achievable by the display device. The physiological characteristics of the human eye mean that when the image brightness is low, small changes in brightness are easily perceived; however, when the image brightness is high, larger changes in brightness are required for the human eye to perceive it.

[0005] The principle of the DICOM curve is to correct the brightness of the 256 gray levels of a display device according to the characteristics of the human eye. This ensures that there are small but sufficiently distinguishable brightness variations between each gray level in the low-brightness portion, and correspondingly larger brightness variations between each gray level in the high-brightness portion. This allows all 256 gray levels to be discerned by the human eye, preventing visual gray-level loss and ultimately achieving accurate medical image viewing and diagnosis. In practical use, it has been found that existing professional medical display devices, in order to ensure DICOM curve compliance, have relatively high brightness levels, such as above 400 nits. Prolonged use of excessively high brightness can damage the user's eyes and increase the power consumption of the display device, thus reducing battery life. Non-professional ordinary monitors, on the other hand, have lower maximum brightness, resulting in insufficient brightness differences between the 256 gray levels, making them indistinguishable to the human eye. This leads to the phenomenon of adjacent gray levels being indistinguishable, known as gray-level loss.

[0006] Existing medical imaging technologies, such as digital X-ray imaging and MRI, are all grayscale images. Medical professionals need to accurately identify the differences between various grayscale levels when making medical image diagnoses. When the brightness difference between two grayscale levels displayed on an LCD screen is too small, the human eye cannot distinguish them, potentially leading to misdiagnosis. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and apparatus for enhancing the color temperature of grayscale medical images, making grayscale medical images easier for doctors to identify, facilitating browsing and diagnosis, and avoiding misdiagnosis.

[0008] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0009] In a first aspect, the present invention provides a method for color temperature enhancement of grayscale medical images, comprising:

[0010] Obtain display characteristic data of the LCD screen;

[0011] The correction value is calculated based on the display feature data;

[0012] Establish a feature correction lookup table for the LCD screen based on the correction values;

[0013] Input and parse a grayscale medical image to obtain RGB input values; convert the RGB input values ​​into RGB output values ​​according to the feature correction lookup table, and generate the corresponding output image for display on an LCD screen.

[0014] Furthermore, the display feature data includes: grayscale pixels W from level 0 to level 255. n Red-level pixels R n Green Scale Pixel G n and blue level pixels B n The corresponding brightness data are denoted as L. Wn L Rn L Gn and L Bn .

[0015] Furthermore, the method for calculating the correction value 'a' based on the display feature data is as follows:

[0016] Calculate the maximum corrected brightness L = L B255 -(L w255 -L w254 );

[0017] Traversing blue-level pixels B n Luminance data L from level 0 to level 255 BnFind the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x, and calculate the correction value a = 255 - x.

[0018] Furthermore, a method for establishing a feature correction lookup table for the LCD screen based on the correction value 'a' is as follows:

[0019] The RGB input value is the grayscale pixel order n of the grayscale pixel Wn; the RGB output value is the color pixel P.

[0020] When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n];

[0021] When grayscale pixel W n When the order n satisfies a < n ≤ (255 - a), it is mapped to the color pixel P = [n + a, n + a, n + a].

[0022] When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to the color pixel P=[255,255,510-na].

[0023] Secondly, the present invention provides a color temperature enhancement device for grayscale medical images, comprising:

[0024] The data storage module is used to acquire and store the display feature data of the LCD screen;

[0025] The control module is used to calculate the correction value based on the display feature data and to establish a feature correction lookup table for the LCD screen based on the correction value.

[0026] The conversion module is used to input and parse grayscale medical images to obtain RGB input values; it then converts the RGB input values ​​to RGB output values ​​according to a feature correction lookup table, and generates the corresponding output image for display on an LCD screen.

[0027] The display feature data includes grayscale pixels W from level 0 to level 255. n Red-level pixels R n Green Scale Pixel G n and blue level pixels B n The corresponding brightness data are denoted as L. Wn L Rn L Gn and L Bn And store it in the data storage module.

[0028] Furthermore, the control module includes the following operation: calculating the correction value 'a' based on the display feature data:

[0029] Based on the display feature data in the data storage module, the maximum corrected brightness L = L is calculated. B255 -(L w255 -L w254 );

[0030] Traversing blue-level pixels B n Luminance data L from level 0 to level 255 Bn Find the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x; calculate the correction value a = 255 - x.

[0031] Furthermore, the control module also includes a feature correction lookup table for the LCD screen based on the correction value 'a':

[0032] The RGB input value is the grayscale pixel order n of the grayscale pixel Wn; the RGB output value is the color pixel P.

[0033] When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n];

[0034] When grayscale pixel W n When the order n satisfies a < n ≤ (255 - a), it is mapped to the color pixel P = [n + a, n + a, n + a].

[0035] When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to the color pixel P=[255,255,510-na].

[0036] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0037] This invention provides a method and apparatus for enhancing the color temperature of grayscale medical images. The method involves acquiring display feature data from a liquid crystal display (LCD) screen, calculating correction values ​​based on the data, and suggesting a suitable feature correction lookup table for converting grayscale pixels to color pixels. The grayscale medical image is then converted according to the lookup table, and the resulting color image is displayed on the LCD screen. This method can improve the brightness difference between low-grayscale pixels and enhance the color temperature difference between high-grayscale pixels, resulting in greater differences between the various grayscale values ​​of the grayscale medical image. This improves the display effect of grayscale medical images displayed on a display device, facilitating human visual recognition and diagnosis. Attached Figure Description

[0038] Figure 1 This is a flowchart illustrating a method for enhancing the color temperature display of grayscale medical images provided by the present invention.

[0039] Figure 2This is a comparison of the input image before correction and the output image after correction in Example 2;

[0040] Figure 3 This is a comparison chart of the brightness and color temperature of each grayscale pixel in the input image before correction and the output image after correction in Example 2. Detailed Implementation

[0041] Currently, most display devices are color monitors. When displaying grayscale images on a color monitor, the principle is to generate the image by mixing the three primary colors (red, green, and blue) of each pixel in equal proportions. The display principle of an LCD screen is to control the amount of backlight transmitted by adjusting the deflection angle of the three liquid crystal cells (red, green, and blue) in each pixel. The transmitted light passes through red, green, and blue color filters, producing combinations of red, green, and blue light in different proportions, ultimately forming the desired signal source color. Most liquid crystal cells can control deflection angles in 256 levels, meaning that the light transmission is minimal at level 0 and maximal at level 255.

[0042] Each pixel of the input signal source can be described by a combination of red, green, and blue components, denoted as [r, g, b]. When the values ​​of r, g, and b are the same, the color of this pixel is gray, called the n-level grayscale. Therefore, each pixel of an LCD screen, with constant backlight brightness, can represent 256 grayscale levels and 256×256×256 color levels, totaling 16,777,216.

[0043] For ease of description, in this invention, P is used to refer to a single pixel in an image, and the red, green, and blue components of the pixel are represented as r, g, and b, respectively, in the form P = [r, g, b]. When the pixel is a grayscale pixel, W is used as the reference. n Let W represent the nth gray level. n =[n,n,n]; when the pixel is a single-color red, green, or blue pixel, it is represented by R respectively. n G n B n Representing the nth order (red, green, and blue), where R... n =[n,0,0],G n = [0,n,0], Bn = [0,0,n]. r, g, b, and n are all integers between 0 and 255.

[0044] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0045] Example 1:

[0046] A method for enhancing the color temperature of grayscale medical images, comprising the following steps:

[0047] Step 1: Obtain the display characteristic data of the LCD screen.

[0048] Step 2: Calculate the correction value based on the display feature data.

[0049] Step 3: Establish a feature correction lookup table for the LCD screen based on the correction values.

[0050] Step 4: Input and parse the grayscale medical image to obtain RGB input values; convert the RGB input values ​​to RGB output values ​​according to the feature correction lookup table, and generate the corresponding output image for display on the LCD screen.

[0051] The display feature data includes: grayscale pixels W from level 0 to level 255. n Red-level pixels R n Green Scale Pixel G n and blue level pixels B n The corresponding brightness data are respectively denoted as L. Wn L Rn L Gn and L Bn .

[0052] Optionally, the method for calculating the correction value 'a' based on the display feature data is as follows:

[0053] (1) Calculate the maximum corrected brightness L = L B255 -(L w255 -L w254 ).

[0054] (2) Traverse the blue pixel B n Luminance data L from level 0 to level 255 Bn Find the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x.

[0055] (3) Calculate the correction value a = 255 - x.

[0056] Optionally, a feature correction lookup table for the LCD screen can be established based on the correction value 'a':

[0057] The RGB input value is the order n of the grayscale pixel Wn; the RGB output value is the color pixel P; the corresponding feature correction lookup table (established from the grayscale pixel Wn) n The mapping relationship to the feature correction lookup table of color pixel P is as follows:

[0058] (1) When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n].

[0059] (2) When grayscale pixel W n When the order n satisfies a<n≤(255-a), it is mapped to the color pixel P=[n+a,n+a,n+a].

[0060] (3) When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to the color pixel P=[255,255,510-na].

[0061] Example 2:

[0062] Based on the color temperature enhancement display method for grayscale medical images provided in Embodiment 1, combined with Figure 1 As shown, the display characteristic data of the LCD screen were first measured, and the results are shown in the table below:

[0063] n <![CDATA[L Rn ]]> <![CDATA[L Gn ]]> <![CDATA[L Bn ]]> <![CDATA[L Wn ]]> 0 0.508 0.509 0.510 0.510 1 0.509 0.511 0.510 0.513 2 0.514 0.531 0.510 0.521 239 103.4 391.3 32.25 525.4 240 104.4 394.8 32.43 529.8 241 105.3 398.2 32.82 534.3 254 117.7 445.7 36.57 593.9 255 118.7 449.5 36.86 598.4

[0064] Based on the above display characteristic data, calculate the maximum corrected brightness L = L B255 -(L w255 -L w254 =32.36, and in table L Bn Find the approximate value L in the column. B240 The order is 240, and the correction value a = 255 - 240 = 15 is calculated.

[0065] Substituting the correction value a = 15 into the lookup table, we obtain the feature correction lookup table for this LCD screen as follows:

[0066] (1) When grayscale pixel W n When the order n satisfies 0≤n≤15, it is mapped to the color pixel P=[2n,2n,2n].

[0067] (2) When grayscale pixel W n When the order n satisfies 15 < n ≤ 240, it is mapped to the color pixel P = [n+15, n+15, n+15].

[0068] (3) When grayscale pixel W n When the order n satisfies 240<n≤255, it is mapped to the color pixel P=[255,255,495-n].

[0069] The input grayscale medical image is parsed to obtain its RGB input values. Then, according to the feature correction lookup table, the RGB input values ​​are converted into RGB output values. Finally, the RGB output values ​​are used to generate an output image, which is then displayed on a display device. Figure 2 As shown, this is a comparison of the input image before correction and the output image after correction in this embodiment; Figure 3 The image shown is a comparison of the brightness and color temperature of each grayscale pixel in the input image before correction and the output image after correction in this embodiment. For example, if the RGB input value of the grayscale medical image is 15, then n = 15, which satisfies 0 ≤ n ≤ 15. This value is mapped to color pixel P = [30, 30, 30], and the image is displayed on the LCD screen according to this color pixel P.

[0070] Example 3:

[0071] Combining the methods described in Embodiments 1 and 2, when the calculated correction value a = 10, the corresponding feature correction lookup table applicable to this LCD screen is obtained as follows:

[0072] (1) When grayscale pixel W n When the order n satisfies 0≤n≤10, it is mapped to the color pixel P=[2n,2n,2n].

[0073] (2) When grayscale pixel W n When the order n satisfies 10 < n ≤ 245, it is mapped to the color pixel P = [n+10, n+10, n+10].

[0074] (3) When grayscale pixel W n When the order n satisfies 245<n≤255, it is mapped to the color pixel P=[255,255,500-n].

[0075] At this time, when the RGB input value of the grayscale medical image is still 15, then n = 15, and it satisfies 10 < n ≤ 245, which is mapped to P = [25, 25, 25], and the color pixel P is displayed on the LCD screen.

[0076] Example 4:

[0077] Referring to the above embodiments, this embodiment provides a color temperature enhancement device for grayscale medical images, including: a data storage module, a control module, and a conversion module.

[0078] The data storage module is used to acquire and store the display feature data of the LCD screen. Specifically, the acquired display feature data includes grayscale pixel W from level 0 to level 255. n Red-level pixels R n Green Scale Pixel G n and blue level pixels B n The corresponding brightness data are denoted as L. Wn L Rn L Gn and L Bn And store it in the data storage module.

[0079] The conversion module is used to input and parse grayscale medical images to obtain RGB input values; it converts the RGB input values ​​into RGB output values ​​according to the feature correction lookup table, and generates the corresponding output image for display on the LCD screen.

[0080] Optionally, the control module includes acquiring display feature data from the data storage module and calculating the correction value 'a'. Specific operations include: identifying the corresponding display feature data and calculating the maximum corrected brightness L = L. B255 -(L w255 -L w254 ).

[0081] Traverse the brightness data L of blue level pixels Bn from level 0 to level 255. Bn Find the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x; calculate the correction value a = 255 - x.

[0082] Optionally, the control module also includes a feature correction lookup table for the LCD screen based on the correction value 'a':

[0083] RGB input values ​​are grayscale pixels W n The order n; the RGB output value is the color pixel P; the mapping relationship of the feature correction lookup table is:

[0084] When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n];

[0085] When grayscale pixel W n When the order n satisfies a < n ≤ (255 - a), it maps to color pixels.

[0086] P = [n+a, n+a, n+a];

[0087] When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to color pixels P=[255,255,510-na]. The grayscale medical image requiring correction is then input into the conversion module for processing and converted into a corresponding output image, which is displayed on the LCD screen.

[0088] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0089] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for enhancing the color temperature of grayscale medical images, characterized in that, include: Obtain display characteristic data of the LCD screen; The correction value is calculated based on the display feature data; Establish a feature correction lookup table for the LCD screen based on the correction values; The input grayscale medical image is processed and converted into a corrected output image according to the feature correction lookup table; The display feature data includes: grayscale pixels W from level 0 to level 255. n Red-level pixels R n Green Scale Pixel G n and blue level pixels B n The corresponding brightness data are denoted as L. Wn L Rn L Gn and L Bn； The method for calculating the correction value 'a' based on the display feature data is as follows: Calculate the maximum corrected brightness L=L B255 -(L w255 -L w254 ); Traversing blue-level pixels B n Luminance data L from level 0 to level 255 Bn Find the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x, and calculate the correction value a = 255 - x; A method for establishing a feature correction lookup table for an LCD screen based on the correction value 'a': When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n]; When grayscale pixel W n When the order n satisfies a<n≤(255-a), it is mapped to the color pixel P=[n+a,n+a,n+a]; When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to the color pixel P=[255,255,510-na].

2. The method for enhancing the color temperature of grayscale medical images according to claim 1, characterized in that, The input grayscale medical image is processed and converted into a corrected output image according to the feature correction lookup table, including: The grayscale medical image is analyzed to obtain RGB input values; the RGB input values ​​are converted into RGB output values ​​according to the feature correction lookup table, and the corrected output image is generated and displayed on the LCD screen.

3. A color temperature enhancement device for grayscale medical images, characterized in that, include: The data storage module is used to acquire and store the display feature data of the LCD screen; The control module is used to calculate the correction value based on the display feature data and to establish a feature correction lookup table for the LCD screen based on the correction value. The conversion module is used to input and parse grayscale medical images to obtain RGB input values; The RGB input values ​​are converted into RGB output values ​​according to the feature correction lookup table, and the corresponding output image is generated and displayed on the LCD screen. The control module calculates the correction value 'a' based on the display feature data as follows: Based on the display feature data in the data storage module, the maximum corrected brightness L=L is calculated. B255 -(L w255 -L w254 ); Traversing blue-level pixels B n Luminance data L from level 0 to level 255 Bn Find the brightness data that is closest to the maximum corrected brightness L, and record the order of the blue level pixel corresponding to the brightness data as x; The correction value is calculated as a = 255 - x; Among them, L B255 This represents the brightness data of the blue-level pixel at level 255; L w255 This represents the brightness data of a grayscale pixel at level 255; L w254 This represents the brightness data of a grayscale pixel at 254 levels. The control module establishes a feature correction lookup table for the LCD screen based on the correction value a: RGB input values ​​are grayscale pixels W n The order n; the RGB output value is the color pixel P; The mapping relationship of the feature correction lookup table is as follows: When grayscale pixel W n When the order n satisfies 0≤n≤a, it is mapped to the color pixel P=[2n,2n,2n]; When grayscale pixel W n When the order n satisfies a<n≤(255-a), it is mapped to the color pixel P=[n+a,n+a,n+a]; When grayscale pixel W n When the order n satisfies (255-a)<n≤255, it is mapped to the color pixel P=[255,255,510-na].

Images