Method for generating holographic optical image

Abstract

The invention relates to the technical field of holographic optics, and discloses a holographic optical image generation method. According to the holographic optical image generation method, required original images are converted into grey-scale images, and the size of a finally generated holographic optical image area, the number of required original images and the position of each original image in the final holographic optical image area are set according to design requirements; the maximum overlapping value between the original images is determined according to the area where the holographic optical image is finally generated and the positions of the original images in the area, the minimum units are divided according to the maximum overlapping value, the original images are processed according to the minimum units, the processed original images are placed in the area where the holographic optical image is finally generated, and the holographic optical image is obtained. And obtaining a gray-scale map of the processed holographic optical image region, and adjusting the grating direction of the region corresponding to the gray-scale value according to the gray-scale value of each point in the gray-scale map of the holographic optical image region to obtain the holographic optical image.

Description

Technical Field

[0001] The present invention relates to the field of holographic optical technology, and specifically to a method for generating a holographic optical image. Background Art

[0002] A holographic optical image is an advanced visual technology based on the principle of light wave optics. Such a pattern not only has unique aesthetics but also can achieve the conversion of the image when observed from multiple angles through design, bringing a unique dynamic performance. Holographic optical patterns are widely used in the fields of high-end packaging design and product anti-counterfeiting. They can not only enhance the attractiveness of products, attract the attention of consumers, but also effectively prevent counterfeit and shoddy products and enhance brand value.

[0003] A holographic optical image can combine multiple pictures. When observed from different angles, different pictures will be revealed. However, existing holographic optical images often present multiple forms under stray light, with blurred patterns and poor dynamic effects. At the same time, the design and production of its dynamic patterns are relatively complex, and the production process is rather cumbersome.

[0004] The prior art relates to the field of holographic optical technology, especially to a method, device, and electronic device for generating a holographic optical image. Although the prior art can achieve the optical effect of sequential display at a specified path and specified interval, it only performs edge contour detection and processing, lacking detection and processing of internal information. In addition, due to problems such as the need for presetting of the path and interval in the prior art and the use of probability filling when processing overlapping regions, designers cannot use non-preset paths or intervals for design, nor can they ensure the effectiveness of the information retained in the overlapping regions, and cannot perform preview and adjustment. This makes the technology have obvious limitations in the field of high-degree-of-freedom design: it is not only difficult to achieve real-time generation preview and dynamic adjustment of holographic optical images, but also difficult to form a user interface convenient for designers to use, and further restricts the development process of related algorithms. Summary of the Invention

[0005] (1) Technical Problems to be Solved

[0006] Aiming at the deficiencies of the prior art, the present invention provides a method for generating a holographic optical image. By combining design requirements, the size of the region for finally generating the holographic optical image, the number of required original images, and the position of each original image in the final holographic optical image region are set to generate the holographic optical image. Designers can freely set the moving path of the image, adjust the image interval and overlapping region, and the degree of uniformity of the overlap can also be adjusted arbitrarily, bringing great freedom to the design of holographic optical images, making the design of holographic optical images more convenient, expanding the design scope of holographic optical images, and solving the above problems.

[0007] (2) Technical Solutions

[0008] To achieve the above object, the present invention provides the following technical solution: A method for generating a holographic optical image, comprising the following steps:

[0009] S1. Convert the required original image into a grayscale image and calculate the average grayscale of each pixel;

[0010] S2. Set the size of the finally generated holographic optical image area, the number of required original images, and the position of each original image in the finally generated holographic optical image area in combination with the design requirements;

[0011] S3. Determine the maximum overlap value between the original images according to the area of the finally generated holographic optical image and the positions of the original images in this area, and calculate the total number of pixels in the overlapping area and the overlap value of the original images;

[0012] S4. Calculate the maximum overlap value according to the overlap value of the original images, divide the minimum unit according to the maximum overlap value, and process the original images according to the minimum unit;

[0013] S5. Place the processed original images in the finally generated holographic optical image area, obtain the grayscale image of the processed holographic optical image area, and calculate the enhanced contrast value of the newly generated holographic image area;

[0014] S6. Adjust the grating azimuth angle of the corresponding area according to the grayscale value of each point in the grayscale image of the holographic optical image area to obtain the final holographic optical image.

[0015] Preferably, the formula for converting the original image into a grayscale image is as follows:

[0016] Gray(i,j) = 0.299R(i,j) + 0.587G(i,j) + 0.114B(i,j)

[0017] In the formula, Gray(i,j) represents the grayscale value of the grayscale image at the position (i,j), R(i,j) represents the red channel value of the original color image at the position (i,j), G(i,j) represents the green channel value of the original color image at the position (i,j), B(i,j) represents the blue channel value of the original color image at the position (i,j), and 0.299, 0.587, and 0.114 are the weight coefficients corresponding to their respective channel values.

[0018] Preferably, setting the size of the finally generated holographic optical image area, the number of required original images, and the position of each original image in the finally generated holographic optical image area in combination with the design requirements is as follows:

[0019] The size of the finally generated holographic optical image area refers to the value range of i and j in Final Area=(i,j);

[0020] The number of required original images is n (n is an integer between 1 and 256);

[0021] The position of each original image in the final holographic optical image area Location(k)=(i k , j k ), where k ranges from 1 to n, indicating the position of the k-th original image.

[0022] Preferably, the calculation formula of the average gray level is as follows:

[0023]

[0024] In the formula, Mean Gray k represents the average gray level of the k-th original image, where k ranges from 1 to n, T represents the total number of pixels in the image, M and N represent the number of rows and columns of the image, and i, j represent the counting subscripts.

[0025] Preferably, the calculation formula of the total number of pixels in the overlapping area is as follows:

[0026] Overlap Pixels = ∑ (i,j)∈Overiap Area Image(i,j)

[0027] In the formula, Overlap Pixels represents the total number of calculated overlapping pixels, Image(i,j) is a conditional function, if there are two or more original image information at (i,j), Image(i,j)=1, otherwise Image(i,j)=0, and Overlap Area represents the overlapping area.

[0028] Preferably, the calculation formula of the original image overlap value is as follows:

[0029]

[0030] In the formula, Overlap value is the original image overlap value, equal to the sum of the I function from I1 to I n , the I k function corresponds to the k-th original image, count(*) represents the statistical function, and Gray k represents the gray level value of the k-th image at the position (i,j), where k ranges from 1 to n.

[0031] Preferably, the calculation formula of the maximum overlap value is as follows:

[0032] Max Overlap value = max(∑ (i,j)∈最终生成平面 Overlap value(i,j))

[0033] In the formula, Max Overlap value represents the maximum overlap value.

[0034] Preferably, the minimum unit is a set of n*n pixel points, and n is the smallest integer satisfying n*n ≥ Max Overlap value.

[0035] Preferably, the formula for calculating the enhanced contrast value of the newly generated holographic image area is as follows:

[0036]

[0037] In the formula, Enhanced Contrast represents the enhanced contrast value of the image, Mean represents the average gray value of the k-th original image after processing, where k ranges from 1 to n, Mean Gray max represents the maximum average gray value in the original image after processing, Mean Gray min represents the minimum average gray value in the original image after processing.

[0038] Preferably, the formula for adjusting the grating azimuth angle is as follows:

[0039] Adjustment(i,j) = k*Gray(i,j)

[0040] In the formula, Adjustment(i,j) represents the adjusted grating azimuth angle, k represents a function based on the gray value, and Gray(i,j) represents the gray value at the corresponding position (i,j).

[0041] Compared with the prior art, the present invention provides a method for generating a holographic optical image, which has the following beneficial effects:

[0042] 1. When the holographic optical image generated by the present invention is irradiated by an external point light source, gratings in different directions will appear in sequence according to the relative angle between the point light source and the human eye, avoiding the display of multiple pictures at the same time, and the pixel uniformity of each part of the original image after processing is better, improving the clear presentation of the holographic optical image.

[0043] 2. The method for dividing the minimum unit according to the maximum overlap value proposed by the present invention brings great freedom to the design of holographic optical images. Without considering the moving path or interval of the image, it only needs to consider the position of the original image in the final holographic optical image area during the design, making the design of holographic optical images more convenient. Designers can freely set the moving path of the image, adjust the image interval and overlapping area, and the degree of uniformity of the overlap can also be adjusted arbitrarily, expanding the design scope of holographic optical images.

[0044] 3. The present invention is easy to form an algorithm and application interface convenient for designers to use. Designers can set the range of the final holographic optical image area, freely import one or some original images, adjust the positions of the original images by moving the mouse or inputting coordinates, preview the finally generated holographic optical image, and modify the above parameters according to the preview situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the method steps of the present invention;

[0046] Figure 2 It is an example diagram of an original image to be processed in the method of the present invention;

[0047] Figure 3 It is a schematic diagram of the array information corresponding to the example diagram of the original image extracted by the method of the present invention;

[0048] Figure 4 It is a schematic diagram of the position of an original image in the finally generated holographic image area in the method of the present invention;

[0049] Figure 5 It is an example diagram of the overlapping situation of an original image in the method of the present invention;

[0050] Figure 6 It is a schematic diagram of reconstructing an original image according to the minimum unit (2×2) in the method of the present invention;

[0051] Figure 7 It is an example diagram of an original image after being processed by the minimum unit reconstruction in the method of the present invention;

[0052] Figure 8 It is an image of an original image example in the method of the present invention after being processed by the minimum unit (6×6);

[0053] Figure 9 It is an example diagram of the grayscale image of a holographic image area after being processed by the method of the present invention;

[0054] Figure 10 An enlarged view of a certain minimum unit (8×8) of the example diagram of the grayscale image of a holographic image area after being processed by the method of the present invention. Detailed implementation mode

[0055] Next, in combination with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0056] Aiming at the problems that the existing holographic optical image generation technology only detects and processes the edge contours, lacks the detection and processing of internal information, and the paths and intervals need to be preset, and probability filling is used when processing overlapping regions, etc., so designers cannot use non-preset paths or intervals for design, nor can they ensure the effectiveness of the information retained in the overlapping regions, and cannot perform preview and adjustment. For this reason, a method for generating a holographic optical image is proposed. Please refer to Figure 1 This method includes the following steps:

[0057] S1. Convert the required original image into a grayscale image and calculate the average grayscale of each pixel;

[0058] The original image is an image designed by a designer through drawing software, etc., and can be patterns of different shapes, such as text, corporate trademarks, etc. In specific implementation, it is necessary to convert the original image required by the designer into a grayscale image, which is convenient for extracting the effective information on the original image;

[0059] Among them, the formula for converting the original image into a grayscale image is as follows:

[0060] Gray(i,j) = 0.299R(i,j) + 0.587G(i,j) + 0.114B(i,j)

[0061] The original color image usually contains three color channels, namely red, green, and blue (RGB). Each pixel needs to store three values, while the grayscale image has only one channel (grayscale value). This significantly reduces the data volume of the image, decreases the data processing requirements, reduces memory consumption, and speeds up the processing speed, making the calculation of the holographic image generation process more efficient. In the formula, Gray(i,j) represents the grayscale value of the grayscale image at position (i,j), R(i,j) represents the red channel value of the original color image at position (i,j), G(i,j) represents the green channel value of the original color image at position (i,j), B(i,j) represents the blue channel value of the original color image at position (i,j), and 0.299, 0.587, and 0.114 are the weight coefficients corresponding to their respective channel values. Using a grayscale image can also better highlight the shape, texture, and details of the image, while color may interfere with the recognition of these features to a certain extent. In addition, in holographic image processing, it is usually necessary to pay more attention to the outline and structure of the object. At this time, using a grayscale image can more effectively discover and analyze these important features;

[0062] The calculation formula for the mean grayscale is as follows:

[0063]

[0064] The calculation of the mean grayscale helps reduce the influence of noise in the image. By obtaining the mean value, the overall image quality can be evaluated in a more accurate way, especially in the presence of interference. The mean is a robust statistic that can reduce the influence of accidental outliers on the grayscale evaluation, thereby improving the stability of subsequent processing steps. In the formula, Mean Gray k represents the mean grayscale of the k-th original image, where k ranges from 1 to n, T represents the total number of pixels in the image, M and N represent the number of rows and columns of the image respectively, and i, j are counting subscripts. When performing image segmentation, classification, or other machine learning tasks, the mean grayscale can be used as part of the feature vector to provide a more reliable background setting for subsequent processing. The accuracy of the mean grayscale directly affects the accuracy of the classification result;

[0065] S2. Combine the design requirements to set the size of the finally generated holographic optical image area, the number of required original images, and the position of each original image in the finally generated holographic optical image area;

[0066] Designers can freely set the size of the finally generated holographic optical area according to the final effect presented by the design, and select the number of original images and the position of each original image in the finally generated area as required;

[0067] The size of the finally generated holographic optical image area is Final Area = the value range of i and j in (i, j), and the number of required original images is n (n is an integer between 1 and 256). The position of each original image in the finally holographic optical image area is Location(k) = (i k , j k ), where k ranges from 1 to n, indicating the position of the k-th original image;

[0068] S3. Determine the maximum overlap value between the original images according to the area of the finally generated holographic optical image and the positions of the original images in this area, and calculate the total number of pixels in the overlapping area and the overlap value of the original images;

[0069] The area of the finally generated holographic optical image is the area of the finally presented holographic optical image designed by the designer, which is equivalent to a "canvas". The area of the holographic optical image on the "canvas", the number of original images, and the position of each original image on this area can all be designed and adjusted by the designer. Among them, the size of the finally generated holographic optical area, the number of original images, and the position of each original image jointly determine the overlapping area and overlap value of the holographic optical image, thus affecting the subsequent holographic effect path, the interval of the original images, and the uniformity of the overlap;

[0070] The calculation formula for the total number of pixels in the overlapping area is as follows:

[0071] Overlap Pixels = ∑ (i,j)∈Overlap Area Image(i, j)

[0072] By calculating the total number of pixels in the overlapping image area with this formula, the weight can be optimized in the algorithm, so that the image quality of the overlapping part is higher and the final stitching effect is also improved. In the formula, Overlap Pixels represents the total number of calculated overlapping pixels, Image(i, j) is a conditional function. If there are two or more original image information at (i, j), Image(i, j) = 1, otherwise Image(i, j) = 0. Overlap Area represents the overlapping area. The calculated total number of pixels in the overlapping area provides a basis for subsequent result verification. For example, when generating a holographic optical image, it can be used to evaluate the final image coverage area or identify whether the merging effect meets the expectations;

[0073] The calculation formula for the overlap value of the original images is as follows:

[0074]

[0075] In the formula, Overlap value is the overlap value of the original images, which is equal to the sum of the I function from I1 to I n sum, Ik The function corresponds to the k-th original image, count(*) represents the statistical function, and Gray k represents the gray value of the k-th image at the position (i,j), where k ranges from 1 to n. If the gray value of the k-th original image at (i,j) is zero, then I k the function is equal to 0, and in other cases it is equal to 1. The user has added n original images in total (where n is greater than 1 and less than 256);

[0076] S4. Calculate the maximum overlap value according to the original image overlap value, divide the minimum unit according to the maximum overlap value, and process the original image according to the minimum unit;

[0077] The above-mentioned minimum unit refers to the basic unit that constitutes the finally generated holographic optical image. For example, if the original image is composed of one pixel point after another, then one pixel point is the basic unit of the original image;

[0078] The above-mentioned minimum unit divided according to the maximum overlap value is the basic unit after the original image is processed by the algorithm and is also the basic constituent unit of the finally generated holographic optical image;

[0079] The maximum overlap value is obtained through the following defined formula:

[0080] Max Overlap value=max(∑ (i,j)∈最终生成平面 Overlap value(i,j))

[0081] The minimum unit is a set of n*n pixel points, and n is the smallest integer that satisfies n*n≥Max Overlap value;

[0082] Process the overlapping original image data according to the overlapping area, reconstruct the original image with the smallest unit, and distinguish each piece of original image information with different gray values. For example, reconstruct the original image according to the smallest unit (2×2). Each smallest unit contains four pixel points. This original image only retains the information at the same position (such as the first pixel point in the upper left corner) in each smallest unit, and modifies the presentation order corresponding to the designed optical holographic image (such as the first appearance). Then, set the retained gray value to 1 (if the gray value of the retained information point is 0, its gray value remains unchanged), and set the gray values of the remaining non-retained pixel points to 0. After that, the subsequent original image in the overlapping area retains the information at a different position from the previous original images in each smallest unit, and modifies the gray value of the retained information according to the presentation order of the optical holographic image. This method not only makes the information pixel points retained in the smallest unit between the overlapping original images at different positions through the processing of the smallest unit, avoiding the mutual interference between the overlapping images, but also is conducive to the subsequent realization of the holographic optical effect by distinguishing each piece of original image information with different gray values;

[0083] S5. Place the processed original image in the finally generated holographic optical image area to obtain the gray-scale image of the processed holographic optical image area, and calculate the enhanced contrast value of the newly generated holographic image area;

[0084] According to the above relevant steps, input the original image information at the backend processed by the smallest unit into the finally generated holographic optical image area according to the position designed by the designer, and the corresponding gray-scale image can be obtained;

[0085] The calculation formula for the enhanced contrast value of the newly generated holographic image area is as follows:

[0086]

[0087] In specific applications, enhanced contrast can help convey information clearly. For example, in the fields of medical imaging, material characterization, etc., clear contrast can help analyze and interpret more complex structures. In the formula, Enhanced Contrast represents the enhanced contrast value of the image, Mean represents the average gray value of the k-th original image after processing, where k ranges from 1 to n, Mean Gray max represents the maximum average gray value in the processed original image, Mean Gray min represents the minimum average gray value in the processed original image. The holographic optical image processed by contrast enhancement is more likely to pass through subsequent processing, such as classification and recognition algorithms, because enhanced contrast makes features more obvious, thereby improving the accuracy of the algorithm;

[0088] S6. Adjust the grating azimuth angle of the corresponding area according to the gray value of each point in the gray scale image of the holographic optical image area to obtain the final holographic optical image;

[0089] In specific implementation, in order to realize that the original image is sequentially displayed according to the relative angle between the point light source and the human eye when illuminated by the point light source, different directions of gratings need to be used for each original image. Designers can adjust by modulating the relationship between the gray value of the effective information of the original image and the corresponding grating azimuth angle to design the required optical effects, including but not limited to the sequential movement and appearance of the same image, the "animation" effect of continuous movement and accompanied by image changes, and the display of different images at different angles at the same position, etc.;

[0090] The formula for adjusting the grating azimuth angle is as follows:

[0091] Adjustment(i,j) = k * Gray(i,j)

[0092] By adjusting the grating direction, the imaging quality and clarity of the holographic image can be optimized, making the performance of the image reach the best. A suitable grating direction will improve the distribution of the light field, thereby making the imaging more realistic. In the formula, Adjustment(i,j) represents the adjusted grating azimuth angle, k represents a function based on the gray value, Gray(i,j) represents the gray value at the corresponding position (i,j). The control of the grating direction can precisely affect the coherence and interference effect of light, change the propagation path of light, thereby obtaining the holographic information required for design, which is crucial for adjusting the optical performance under imaging conditions.

[0093] Through the comprehensive application of the above methods, the holographic optical image generation method provided by the present invention can not only avoid the display of multiple pictures at the same time, improve the clear presentation of the holographic optical image, but also bring great freedom to the design of the holographic optical image, making the design of the holographic optical image more convenient and expanding the design scope of the holographic optical image.

[0094] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for generating a holographic optical image, characterized in that, It includes the following steps: S1. Convert the required original image into a grayscale image and calculate the average grayscale of each pixel; S2. Set the size of the finally generated holographic optical image area, the number of required original images, and the position of each original image in the finally generated holographic optical image area in combination with the design requirements; S3. Determine the maximum overlap value between the original images according to the area of the finally generated holographic optical image and the positions of the original images in this area, and calculate the total number of pixels in the overlapping area and the original image overlap value; S4. Calculate the maximum overlap value according to the original image overlap value, divide it into the smallest units according to the maximum overlap value, and process the original images according to the smallest units; S5. Place the processed original images in the finally generated holographic optical image area, obtain the grayscale image of the processed holographic optical image area, and calculate the enhanced contrast value of the newly generated holographic image area; S6. Adjust the grating azimuth angle of the corresponding area according to the grayscale value of each point in the grayscale image of the holographic optical image area to obtain the final holographic optical image.

2. The generating method of a holographic optical image according to claim 1, wherein: The formula for converting the original image into a grayscale image is as follows: Gray(i,j) = 0.299R(i,j) + 0.587G(i,j) + 0.114B(i,j) In the formula, Gray(i,j) represents the grayscale value of the grayscale image at the position (i,j), R(i,j) represents the red channel value of the original color image at the position (i,j), G(i,j) represents the green channel value of the original color image at the position (i,j), B(i,j) represents the blue channel value of the original color image at the position (i,j), and 0.299, 0.587, and 0.114 are the weight coefficients corresponding to their respective channel values.

3. The method for generating a holographic optical image according to claim 2, wherein: The setting of the size of the finally generated holographic optical image area, the number of required original images, and the position of each original image in the finally generated holographic optical image area in combination with the design requirements is as follows: The size of the finally generated holographic optical image area designed refers to the value range of i and j in FinalArea = (i,j); The number of required original images is n (n is an integer between 1 and 256); The position Location(k) of each original image in the final holographic optical image region is (i k , j k ), where k ranges from 1 to n, representing the position of the k-th original image.

4. A method for generating a holographic optical image according to claim 3, characterized in that: The calculation formula for the average grayscale is as follows: In the formula, Mean Gray k represents the mean gray level of the k-th original image, where k ranges from 1 to n, T represents the total number of pixels in the image, M and N represent the number of rows and columns of the image, and i, j represent the counting subscripts.

5. A method for generating a holographic optical image according to claim 4, characterized in that: The calculation formula for the total number of pixels in the overlapping area is as follows: Overlap Pixels = ∑ (i,j)∈Overlap Area Image(i, j) In the formula, Overlap Pixels represents the total number of overlapping pixels calculated, Image(i,j) is a conditional function, if there are two or more original image information at (i,j), Image(i,j) = 1, otherwise Image(i,j) = 0, and OverlapArea represents the overlapping area.

6. A method for generating a holographic optical image according to claim 5, characterized in that: The calculation formula for the original image overlap value is as follows: In the formula, the Overlap value is the original image overlap value, which is equal to the sum of the I function from I1 to I n , I k The function corresponds to the k-th original image, count(*) represents the statistical function, and Gray k represents the gray value of the k-th image at the position (i, j), where k ranges from 1 to n.

7. A method for generating a holographic optical image according to claim 6, characterized in that: The calculation formula for the maximum overlap value is as follows: Max Overlap value=max(∑ (i,j)∈最终生成平面 Overlap value(i,j)) In the formula, Max Overlap value represents the maximum overlap value.

8. A method for generating a holographic optical image according to claim 7, characterized in that: The smallest unit is a set of n*n pixel points, and n is the smallest integer that satisfies n*n ≥ Max Overlap value.

9. A method for generating a holographic optical image according to claim 8, characterized in that: The calculation formula for the enhanced contrast value of the newly generated holographic image area is as follows: In the formula, Enhanced Contrast represents the enhanced contrast value of the image, represents the average gray value of the k-th original image after processing, where k ranges from 1 to n, Mean Gray max represents the maximum average gray value in the original image after processing, Mean Gray min represents the minimum average gray value in the original image after processing.

10. A method for generating a holographic optical image according to claim 9, characterized in that: The formula for adjusting the grating azimuth angle is as follows: Adjustment(i,j) = k * Gray(i,j) In the formula, Adjustment(i,j) represents the adjusted grating azimuth angle, k represents a function based on the gray value, and Gray(i,j) represents the gray value at the corresponding position (i,j).

Images