Imaging positioning yin-yang-like strip code and construction method and decoding method thereof

Abstract

The application discloses a yin-yang divination strip code for imaging positioning and a construction method and a decoding method thereof. A plurality of sub-regions are arranged on a light-emitting surface. Yin-yang divination strip patterns are arranged in the sub-regions respectively, and are used for representing identity information. The yin-yang divination strip patterns comprise yin divination strips and yang divination strips. The yin divination strips and the yang divination strips are alternatively arranged in a single sub-region. A blank strip is arranged in a first sub-region, and is used for representing an information start symbol. The yin-yang divination strip code has the characteristics of simple structure, easy manufacturing and low decoding complexity, and can still maintain high robust positioning performance in various complex environments. The yin-yang divination strip code can effectively reduce the complexity of a positioning anchor point device and the cost of a system.

Description

Technical Field

[0001] This invention relates to the fields of photogrammetry and visible light imaging positioning technology, specifically to a simulated yin-yang barcode for imaging positioning, and its construction and decoding methods. Background Technology

[0002] Imaging Visible Light Positioning (iVLP) is an indoor positioning technology based on Visible Light Communication (VLC). Utilizing LED lighting infrastructure, it can be applied in indoor scenarios such as large supermarkets, shopping malls, large parking lots, and factory automated guided vehicle (AGV) navigation, providing positioning and navigation for pedestrians and AGVs. iVLP can also be applied outdoors. Specifically, customized LED flat panel lights can be installed on streetlight poles to provide directional navigation services for pedestrians or autonomous vehicles, overcoming the limitation of GPS and BeiDou systems in providing directional navigation for stationary pedestrians.

[0003] iVLP technology boasts advantages such as zero electromagnetic pollution, environmental friendliness, and high safety. Meanwhile, LEDs, with their energy-saving, environmentally friendly, and uniform light emission, have become the preferred choice for indoor lighting. Furthermore, iVLP employs photogrammetry and computer vision technologies, resulting in higher accuracy compared to other positioning technologies, with an average system positioning error reaching the centimeter level.

[0004] Existing visible light imaging localization methods also have some problems. For example, a method for detecting LED flicker frequency based on a CMOS image sensor (application number 201510809219.0) proposes a method that uses the rolling shutter effect of the CMOS image sensor to generate a stripe image on the imaging surface, and then analyzes and calculates the flicker frequency of the LED by performing FFT transformation on the stripe image. Although this method can be applied to transmit LED identification information (e.g., patent application 201510809216.7 - A method for transmitting and detecting LED information based on a CMOS image sensor), it requires the design of a dedicated LED driving modulation circuit, and the decoding complexity of the receiver is also high. Based on this, a visual reference method for visible light localization (application number 202210510786.6) designs a mechanism based on the Manchester one-dimensional visual reference mechanism to generate a bright and dark stripe image carrying LED-ID information, and proposes a corresponding decoding method. However, this method has high decoding complexity, low robustness, and a limited number of feature points (the four corner points of the flat panel light) for PnP localization, so the localization accuracy needs to be improved.

[0005] Based on the above problems, this invention proposes a method for creating and decoding a simulated Yin-Yang barcode based on a rectangular light-emitting surface by simply modifying existing LED flat panel lights. This method is expected to overcome some of the shortcomings and defects of traditional imaging and positioning technologies. Summary of the Invention

[0006] The purpose of this invention is to address the problems existing in the prior art by providing a simulated Yin-Yang barcode for imaging positioning, as well as its construction and decoding methods.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, a simulated yin-yang barcode for imaging positioning is provided, comprising several sub-regions disposed on a light-emitting surface, wherein each sub-region is provided with a yin-yang barcode pattern to represent identification information, wherein the yin-yang barcode pattern includes yin barcodes and yang barcodes, and one of the yin barcodes and the yang barcodes is disposed in a single sub-region; a blank barcode is provided in the first sub-region to represent an information start character.

[0008] This invention applies the yin-yang symbol pattern, which combines characteristics and regularity, to image information transmission systems. It has advantages such as strong noise resistance, high visual recognition, and direction independence. It can be combined to form many patterns to describe information in the complex world. Moreover, the yin-yang stripe pattern can be well applied to existing LED flat panel lights. The modification is very simple. Just set the stripes on the light-emitting surface. There is no need for complicated engraving and it does not affect the lighting effect of the light fixture itself.

[0009] Furthermore, the light-emitting surface is rectangular, and the sub-regions are vertical rectangular regions arranged sequentially along the length of the light-emitting surface, with several sub-regions having the same size.

[0010] Furthermore, the yin and yang stripes are vertically arranged in the center of the sub-region, and multiple dark-colored marker blocks are provided in the blank stripes near the edge of the luminous surface.

[0011] Furthermore, the light-emitting surface is the light-emitting surface of the LED flat panel light fixture, and the yin-yang stripe pattern is engraved on the light-emitting surface. This allows for simple modification of existing indoor LED flat panel light fixtures, enabling them to be used as reference markers for indoor positioning. This effectively avoids the shortcomings of traditional guide rail marker positioning and autonomous positioning, reducing positioning and navigation costs.

[0012] Furthermore, the length of the luminous surface of the rectangle is defined as... L , width is W The length of the transmitted identity information is I bits, then if it represents a length of IThe bit's identity recognition information divides the luminous surface into equal parts along its long side. N A =I+ 1 sub-region, each sub-region having a length of L A =W , width is The unit is mm.

[0013] Secondly, a method for constructing a simulated Yin-Yang barcode for imaging positioning is provided, the method comprising the following steps: Define the length of the luminous surface of the rectangle as L , width is W The length of the transmitted identity information is I Bits, the length of the subregion is L A Width is W A ; Define the length and width of the yin-yang stripe pattern set within the sub-region as follows: ,in The gap distance between the yin and yang stripe patterns is... W g for: , The distance of the yin-yang stripe pattern from the long edge L E Distance from the short edge W E They are respectively: ; Let the length of each segment of the negative line stripe be... L B The interval between the two segments is L g Then we have: , , .

[0014] Furthermore, a length of [missing information] is provided at the edge of the blank stripe area of ​​the luminescent surface. L O Width W O The first dark-colored marker block is used for left-right direction determination; a length of [missing information] is provided at the upper or lower edge of the blank striped area. L P Width W P The second dark-colored marker is used to determine the up and down direction.

[0015] Thirdly, a decoding method for a simulated Yin-Yang barcode used for imaging positioning is provided, the decoding method comprising the following steps: Image preprocessing: Convert the captured image to a grayscale image, identify the grayscale image, and perform edge extraction; Image integrity detection and extraction of four corner points of the luminous surface: The edge contour of the grayscale image is located, and its incompleteness is determined by whether the grayscale image touches the boundary and whether it has four vertices; the pixel coordinates of the four corner points of the complete grayscale image are obtained, defined as... ,in i =0, 1, 2, 3. and For the two corner points closest to the edge of the blank stripe, and These are the other two corresponding corner points; Determining the boundary by connecting the center points of the two longest sides: Traverse the four sides of the contour, select the two longest sides, and divide the line segments of the two longest sides into equal parts. N A Divide into equal parts, then there is a line segment N A Adding 1 point, the coordinates of the center point of each column of the yin-yang stripe pattern on a long side are represented as follows: ,in Similarly, the coordinates of the center point on the other longer side are represented as: Connect the center points of each column of yin-yang stripe patterns on both sides, so that each line can pass through each yin-yang stripe pattern in the sub-region. Direction determination: Set left and right search areas for left and right direction determination and up and down search areas for up and down direction determination. The area with the smaller sum of gray values ​​in the left and right search areas is the left end, and the area with the smaller sum of gray values ​​in the up and down search areas is the top end. right N A The square area at the center point of the pixel of the yin-yang stripe pattern is grayscale determined and decoded, and the decoded data is assembled into identity information. The projection distances of the yin-yang stripe patterns are sorted from smallest to largest, and the decoding information of the yin-yang stripe patterns is reorganized according to the sorting results.

[0016] Furthermore, in the image integrity detection step, a contour detection algorithm is used to find the contours of the grayscale image. All found contours are sorted by area, and the contour with the largest area is selected. The minimum bounding rectangle function of the contour is used to find the coordinates of the four circumscribed vertices. Then, the parameter tolerance is used to determine whether the image touches the boundary. If it touches the boundary, it is considered incomplete. The polygon vertex coordinates are obtained through the contour approximation function, and it is determined whether the number of vertices is 4. If not, the image is considered incomplete.

[0017] Furthermore, in the direction determination step, the center points of the two short sides of the contour are first found, all pixels on the line segment are obtained, and the total length of the line segment is obtained; the left and right directions are determined by using the two ends of the line connecting the midpoints of the short sides. As the left and right search areas, the up and down directions are determined using the two ends of the blank stripe connection. As the upper and lower search areas, the sum of the gray values ​​of the left and right search areas and the upper and lower search areas at both ends of the line segment is calculated respectively, and their magnitudes are compared. In the formula, L The length of the luminous surface. W The width of the luminous surface. W O The width of the dark markings along the left and right edges of the blank stripes. L P The length of the dark marker blocks at the top and bottom edges of the blank stripe.

[0018] Compared with existing technologies, the beneficial effects of this invention are: 1. The simulated Yin-Yang barcode for imaging positioning in this invention has the characteristics of simple structure, easy manufacturing, and low decoding complexity. It also maintains high robust positioning performance under various complex environments, effectively reducing the complexity of positioning anchor point equipment and lowering system costs; 2. The Yin-Yang barcode pattern can be obtained by laser engraving frosted stripes on the light guide plate of an LED flat panel lamp. This simple manufacturing process effectively reduces the complexity of positioning anchor point equipment. Compared to existing stripe images generated based on the rolling shutter effect of CMOS image sensors, it eliminates the need to design LED lamp driving modulation circuits, thereby avoiding the need for designing the transmitter in an iVLP system. 3. Compared to the existing Manchester barcode visual method for LED flat panel lights, the decoding method of this barcode pattern is simpler, has better robustness in complex environments, obvious feature points, and higher positioning accuracy; 4. This construction method can scientifically and accurately construct the yin and yang barcodes on the light-emitting surface. Different identity information can be expressed through the set arrangement and combination. Moreover, the yin and yang barcode patterns constructed by this method are easy to identify and decode in the future, and can effectively obtain the identity information they express; 5. This decoding method is less difficult, the flat panel light barcode is simple and easy to observe, and imaging and positioning can be achieved without affecting the lighting. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the construction of a simulated Yin-Yang barcode for imaging positioning according to the present invention. Figure 2 This is a schematic diagram of the LED flat panel lamp with simulated yin-yang barcodes engraved according to the present invention when the lamp is turned off. Figure 3 This is a flowchart of the LED-ID decoding and camera orientation estimation process of the present invention; Figure 4 This is a schematic diagram of the LED flat panel lamp with simulated yin-yang barcodes engraved according to the present invention when the lamp is lit. Figure 5 This is a schematic diagram of the edge recognition results in the image processing of this invention; Figure 6 This is a schematic diagram showing the coordinates of the four corner points of the outer contour of the light-emitting surface of the flat panel lamp of the present invention; Figure 7 This is a schematic diagram of the outer rotating contour of the light-emitting surface of the flat panel lamp of the present invention (blue contour). Figure 8 This is a schematic diagram of the stripe connection of the flat panel lamp of the present invention; Figure 9 This is a schematic diagram illustrating the direction determination of the flat panel light according to the present invention; Figure 10 This is a schematic diagram illustrating the determination of the grayscale value of the pixel at the center point of the line connecting different types of stripes in this invention. Figure 11 This is a schematic diagram of the direction determination process for the ID decoding of a flat panel light in this invention; Figure 12 This is a schematic diagram illustrating the pixel coordinates of the centroid of the dark striped rectangular block in the striped image of this invention.

[0020] In the diagram: 1. Illuminated surface; 2. Sub-area; 3. Yin-Yang stripe pattern; 301. Yin stripe; 302. Yang stripe; 4. First dark-colored marker block; 5. Second dark-colored marker block; 6. LED flat panel light fixture. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of this invention, it should be noted that the terms "middle," "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for 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. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] Example 1: A simulated Yin-Yang barcode for imaging positioning is provided, such as... Figure 1 As shown, the sub-regions 2 are provided on the light-emitting surface 1. Each sub-region 2 is provided with a yin-yang stripe pattern 3 to represent identification information. The yin-yang stripe pattern 3 includes yin stripe 301 and yang stripe 302. The yin stripe 301 and the yang stripe 302 are selectively provided in a single sub-region 2. A blank stripe is provided in the first sub-region 2 to represent the information start character.

[0024] The Yin-Yang barcode of this invention for imaging positioning has the characteristics of simple structure, easy manufacturing, low decoding complexity, and can maintain high robust positioning performance in various complex environments. It can effectively reduce the complexity of positioning anchor point equipment and reduce system cost.

[0025] This invention creatively applies the simple symbolic pattern of yin and yang lines to an image information transmission system, offering advantages such as strong noise resistance, high visual recognition, and direction independence. A yang line "—" represents 0, and a yin line "- -" represents 1. Combinations of six lines can form 64 different patterns, capable of describing information in a complex world, much like how computers use "0" and "1" to construct the digital world. The yin and yang stripe pattern can be readily applied to existing LED flat panel lights, requiring only simple modification—stripes are simply added to the light-emitting surface—without complex engravings or affecting the lighting effect of the light fixture itself.

[0026] This invention is based on the length of the transmitted identity (ID) information. I The bit divides the light-emitting surface 1 into multiple sub-regions 2. The yin-yang stripe pattern 3 set in each sub-region 2 can represent the identification information (LED-ID). The sub-region at the starting position uses a blank stripe to represent the information start symbol. There is no need to set the yin-yang stripe pattern. Setting some dark-colored marker blocks can be used to determine the direction.

[0027] Furthermore, the light-emitting surface 1 is rectangular, and the sub-region 2 is a vertical rectangular region arranged sequentially along the length of the light-emitting surface 1. Several sub-regions 2 have the same size, that is, the same area, to ensure that each sub-region is consistent. The difference lies in the stripe pattern within it.

[0028] Furthermore, the yin stripe 301 and the yang stripe 302 are respectively arranged vertically in the center of the sub-region 2, and multiple dark-colored marker blocks are provided in the blank stripe near the edge of the light-emitting surface.

[0029] Furthermore, the light-emitting surface 1 is the light-emitting surface of the LED flat panel lamp 6, such as... Figure 2 As shown, the yin-yang stripe pattern 3 is engraved on the luminous surface 1.

[0030] The yin-yang stripe pattern 3 can be obtained by laser engraving frosted stripes on the light guide plate of the LED flat panel lamp 6. This method is simple to produce and effectively reduces the complexity of the positioning anchor point equipment. Compared with the existing stripe image generated by the roller blind effect based on CMOS image sensor, there is no need to design the LED lamp driving modulation circuit, thus avoiding the problem of increased equipment complexity of the iVLP system transmitter.

[0031] The present invention, which directly engraves yin-yang stripe patterns on the light-emitting surface of LED flat panel lamps, has a simpler decoding method than the existing Manchester barcode visual method of LED flat panel lamps. It also has better robustness in complex environments, obvious feature points, and higher positioning accuracy.

[0032] Furthermore, the length of the luminous surface of the rectangle is defined as... L , width is W The length of the transmitted identity information is I bits, then if it represents a length of I The bit's identity recognition information divides the luminous surface into equal parts along its long side. N A =I+1 Block regions, each block region has a length of L A =W , width is The unit is mm.

[0033] Example 2: A method for constructing a simulated Yin-Yang barcode for imaging positioning is provided.

[0034] The construction method includes the following steps: Define the length of the luminous surface of the rectangle as L , width is W The length of the transmitted identity information is I Bits, the length of the subregion isL A Width is W A ; Define the length and width of the yin-yang stripe pattern set within the sub-region as follows: ,in The gap distance between the yin and yang stripe patterns is... W g for: , The distance of the yin-yang stripe pattern from the long edge L E Distance from the short edge W E They are respectively: ; Let the length of each segment of the negative line stripe be... L B The interval between the two segments is L g Then we have: , , .

[0035] The above construction method can scientifically and accurately construct the yin and yang stripes on the light-emitting surface. Different identity information can be expressed through the set arrangement and combination. Moreover, the yin and yang stripe patterns constructed by this method are easy to identify and decode in the future, and the identity information they express can be well obtained.

[0036] Furthermore, in combination Figure 1 As shown, a length of [missing information] is provided at the edge of the blank stripe area of ​​the luminous surface 1. L O Width W O The first dark-colored marker block 4 is used for left-right direction determination; a length of [missing information] is provided at the upper or lower edge of the blank stripe area. L P Width W P The second dark-colored marker block 5 is used to determine the up and down direction.

[0037] Combination Figure 1 As shown, a specific construction method is given: the length of the rectangular luminescent surface is... L , width is W Length of transmitted ID information I =8 bits, then the light-emitting surface needs to be divided into equal parts along its long side. NA =9 sub-regions, each sub-region having a length of L A = Wmm, width is W A = 1 / 9·Lmm; Let the yin line stripe represent the information "1" and the yang line stripe represent the information "0". Additionally, the length of the yin and yang line stripe patterns set in the sub-regions... mm, where α = 4 / 5, and the width is mm, where β=3 / 4, and each stripe pattern is centered in the sub-region, then adjacent yin and yang stripe patterns (including yin stripe and yang stripe, yin stripe and yin stripe, and yang stripe and yang stripe) have a distance between them. =1 / 4· W A The gap is mm, and the distance between the yin-yang stripe pattern and the long edge of the rectangular luminous surface is... .

[0038] Example 3: A decoding method for the simulated Yin-Yang barcode used for imaging positioning in Example 2 is provided. Figure 2 The demonstration showcased an LED flat panel light fixture with a yin-yang stripe pattern engraved on its luminous surface. The light fixture was in a non-powered state. The first sub-area from the left was a blank stripe, which indicated the starting position of the decoding direction. Once the starting position was determined, the LED-ID number could be decoded from the yin-yang stripe pattern on the rectangular luminous surface, regardless of the shooting direction.

[0039] Combination Figure 3 As shown, the decoding method includes the following steps: (1) Image preprocessing: Convert the captured image into a grayscale image, identify the grayscale image and perform edge extraction; Specifically, the captured image (picture) is first converted to a grayscale image, and then an edge detection algorithm is used to identify the edges of the grayscale image, such as... Figures 4-5 As shown.

[0040] (2) Image integrity detection and extraction of four corner points of the luminous surface: Locate the edge contour of the grayscale image, and determine whether the grayscale image is incomplete by whether the grayscale image touches the boundary and whether the number of vertices is four; obtain the pixel coordinates of the four corner points under the complete grayscale image, defined as , where i = 0, 1, 2, 3. and For the two corner points closest to the edge of the blank stripe, and For the other two corresponding corner points, such as Figure 6 and Figure 7As shown; Specifically, a contour detection algorithm is used to find the contours of the grayscale image. All found contours are sorted by area, and the contour with the largest area is selected. The minimum bounding rectangle function is used to calculate the coordinates of the four circumscribed vertices. Then, the parameter tolerance is used to determine whether the image touches the boundary. If it touches the boundary, it is considered incomplete. The polygon vertex coordinates are obtained through a contour approximation function, and it is determined whether the number of vertices is 4. If not, the image is considered incomplete.

[0041] (3) Determining the center point of the long side equally divided: Traverse the four sides of the contour, select the two long sides of the contour, and divide the two long side segments into equal parts. N A Divide into equal parts, then there is a line segment N A Adding 1 point, the coordinates of the center point of each column of the yin-yang stripe pattern on a long side are represented as follows: ,in Similarly, the coordinates of the center point on the other longer side are represented as: ; combination Figure 8 As shown, the center points of each column of the yin-yang stripe pattern on both sides are connected by a line so that each line passes through each yin-yang stripe pattern in the sub-region.

[0042] (4) Direction determination: Set the left and right search areas for left and right direction determination and the up and down search areas for up and down direction determination. The area with the smaller sum of gray values ​​in the left and right search areas is the left end, and the area with the smaller sum of gray values ​​in the up and down search areas is the top end. Specifically, first, the center points of the two short sides of the contour are found, and the Bresenham algorithm is used to obtain all pixels on the line segment and the total length of the line segment is obtained; the left and right directions are determined by connecting the two ends of the line with the midpoint of the short side. As the left and right search areas, the up and down directions are determined using the two ends of the blank stripe connection. As the upper and lower search areas, the sum of the gray values ​​of the left and right search areas and the upper and lower search areas at both ends of the line segment is calculated respectively, and their magnitudes are compared. Figure 9 As shown, in the left-right judgment, the region with the smaller sum of gray values ​​is the left edge; in the top-bottom judgment, the region with the smaller sum of gray values ​​is the top edge. In the formula, L The length of the luminous surface. W The width of the luminous surface. W O The width of the dark markings along the left and right edges of the blank stripes. L P The length of the dark marker blocks at the top and bottom edges of the blank stripe.

[0043] (5) N AThe grayscale determination and decoding process is performed on a square area centered on the pixel center of the yin-yang stripe pattern: The coordinates of the center point are obtained based on the stripe length. Using this coordinate point as the center, a square area is selected, and the average grayscale value of all pixels within this area is obtained. R i All grayscale values ​​are combined into a sequence, and an adaptive threshold is obtained by performing Otsu's algorithm. R T Finally, a decoding decision is made based on the obtained threshold result; Specifically, such as Figure 10 As shown, this is a specific implementation of grayscale threshold-based decoding. The adaptive threshold obtained using Otsu is 1, while line segment 2 ( R 2 The center gray value is greater than the adaptive threshold, i.e., R² > R. T According to the definition, line segment 2 is judged as "1"; line segment 3 ( R 3 The center gray value is less than the threshold, i.e., R3 <R T According to the definition, line segment 3 is judged as "0". At this time, although the blank stripe period also participates in the judgment, the final result does not affect the ID decoding. Finally, the decoded data is assembled into LED-ID information.

[0044] (6) LED-ID information sorting and reorganization: Sort the projection distances of the yin-yang stripe patterns from smallest to largest, and reorganize the identity identification of the decoded information of the yin-yang stripe patterns according to the sorting results; Specifically, first, the coordinates of the midpoint of the short edge of the LED flat panel light fixture are extracted, and the left and right direction vectors are calculated. Then, the coordinates of the center point of the line connecting all the yin-yang stripe patterns are calculated, and the vector from the center point of the left edge to the center point of each stripe is calculated. Then, its projection length is calculated. The stripes are sorted in ascending order of projection distance (to determine the order from left to right). Finally, the LED-ID of the decoded yin-yang stripe pattern is reconstructed according to the sorting result. In this process, the first position of the sequence, i.e., the blank stripe, is ignored, and the reconstruction starts directly from the second position. Figure 11 To illustrate the example diagram, the final decoding result in this example is 10010110.

[0045] To further improve the positioning performance of precise positioning, this invention proposes a method for extracting the pixel coordinates of the centroid points of dark striped rectangular blocks in the imaging surface (light-emitting surface) of LED flat panel lamps. This method serves as a feature reference point for precise PnP positioning, combined with... Figure 12 As shown, the specific steps are as follows: (1) Preprocess the acquired images and perform Otsu threshold segmentation of the ROI region; (2) After contour detection, filter out internal contours that are too large or too small; (3) The centroid is obtained by using the image moment method based on the internal contour. The obtained internal contour centroid is the feature reference point.

[0046] Compared with traditional indoor navigation and positioning, the simulated yin-yang barcode and its decoding method of this invention have the advantages of low cost, no need for pre-installed marking devices, small construction workload, and high positioning accuracy. The decoding difficulty of this invention is lower, the barcode of the flat panel light is simple and easy to observe, and positioning can be performed without affecting lighting.

[0047] It should be noted that, inspired by the yin-yang symbol pattern, three-segment symbols “- - -” and four-segment symbols “- -- -” can be designed. Combinations of yin-yang symbols and three- or four-segment symbols can represent 2-bit information. All higher-order symbol patterns extended from this yin-yang symbol pattern and their corresponding decoding methods are protected under this patent.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A simulated Yin-Yang barcode for imaging and positioning, characterized in that, It includes several sub-regions set on the light-emitting surface, each sub-region having a yin-yang stripe pattern to represent identification information. The yin-yang stripe pattern includes yin stripes and yang stripes, and one of the yin stripes and the yang stripes is set in a single sub-region. A blank stripe is set in the first sub-region to represent the information start character.

2. The simulated Yin-Yang barcode for imaging positioning according to claim 1, characterized in that, The light-emitting surface is rectangular, and the sub-regions are vertical rectangular regions arranged sequentially along the length of the light-emitting surface, with several sub-regions having the same size.

3. The simulated Yin-Yang barcode for imaging positioning according to claim 1, characterized in that, The yin and yang stripes are arranged vertically in the center of the sub-region, and multiple dark-colored marker blocks are arranged near the edge of the light-emitting surface within the blank stripes.

4. The simulated Yin-Yang barcode for imaging positioning according to claim 1, characterized in that, The light-emitting surface is the light-emitting surface of the LED flat panel lamp, and the yin-yang stripe pattern is engraved on the light-emitting surface.

5. The simulated Yin-Yang barcode for imaging positioning according to claim 1, characterized in that, Define the length of the luminous surface of the rectangle as L , width is W The length of the transmitted identity information is I bits, then if it represents a length of I The bit's identity recognition information divides the luminous surface into equal parts along its long side. N A =I+1 Block regions, each block region has a length of L A =W , width is The unit is mm.

6. The method for constructing a simulated Yin-Yang barcode for imaging positioning according to any one of claims 1 to 5, characterized in that, The construction method includes the following steps: Define the length of the luminous surface of the rectangle as L , width is W The length of the transmitted identity information is I Bits, the length of the subregion is L A Width is W A ; Define the length and width of the yin-yang stripe pattern set within the sub-region as follows: ,in The gap distance between the yin and yang stripe patterns is... W g for: ， The distance of the yin-yang stripe pattern from the long edge L E Distance from the short edge W E They are respectively: ； Let the length of each segment of the negative line stripe be... L B The interval between the two segments is L g Then we have: ， ， 。 7. The method for constructing a simulated Yin-Yang barcode for imaging positioning according to claim 6, characterized in that, A length of [length missing] is provided at the edge of the blank stripe area of ​​the luminescent surface. L O Width W O The first dark-colored marker block is used for left-right direction determination; a length of [missing information] is provided at the upper or lower edge of the blank striped area. L P Width W P The second dark-colored marker is used to determine the up and down direction.

8. The decoding method for the simulated Yin-Yang barcode for imaging positioning according to any one of claims 1 to 5, characterized in that, The decoding method includes the following steps: Image preprocessing: Convert the captured image to a grayscale image, identify the grayscale image, and perform edge extraction; Image integrity detection and extraction of four corner points of the luminous surface: find the edge contour of the grayscale image, and determine whether the grayscale image is incomplete by whether the grayscale image touches the boundary and whether the number of vertices is four; To obtain the pixel coordinates of the four corner points of a complete grayscale image, define as follows: , where i = 0, 1, 2, 3. and For the two corner points closest to the edge of the blank stripe, and These are the other two corresponding corner points; Determining the boundary by connecting the center points of the two longest sides: Traverse the four sides of the contour, select the two longest sides, and divide the line segments of the two longest sides into equal parts. N A Divide into equal parts, then there is a line segment N A +1 If there are 10 points, then the coordinates of the center point of each column of the yin-yang stripe pattern on one of the long sides are represented as follows: ,in Similarly, the coordinates of the center point on the other longer side are represented as: Connect the center points of each column of yin-yang stripe patterns on both sides, so that each line can pass through each yin-yang stripe pattern in the sub-region. Direction determination: Set left and right search areas for left and right direction determination and up and down search areas for up and down direction determination. The area with the smaller sum of gray values ​​in the left and right search areas is the left end, and the area with the smaller sum of gray values ​​in the up and down search areas is the top end. right N A The grayscale determination and decoding of the square area at the center point of the pixel of the yin-yang stripe pattern is performed, and the decoded data is assembled into identity information. The projection distances of the yin-yang stripe patterns are sorted from smallest to largest, and the decoding information of the yin-yang stripe patterns is reorganized according to the sorting results.

9. The decoding method for the simulated Yin-Yang barcode for imaging positioning according to claim 8, characterized in that, In the image integrity detection step, a contour detection algorithm is used to find the contours of the grayscale image. All found contours are sorted by area, and the contour with the largest area is selected. The minimum bounding rectangle function of the contour is used to find the coordinates of the four circumscribed vertices. Then, the parameter tolerance is used to determine whether the image touches the boundary. If it touches the boundary, it is considered incomplete. The polygon vertex coordinates are obtained through the contour approximation function, and it is determined whether the number of vertices is 4. If not, the image is considered incomplete.

10. The decoding method for the simulated Yin-Yang barcode for imaging positioning according to claim 8, characterized in that, In the direction determination step, firstly, the center points of the two short sides of the contour are found, all pixels on the line segment are obtained, and the total length of the line segment is calculated; the left and right directions are determined by connecting the two ends of the line with the midpoints of the short sides. As the left and right search areas, the up and down directions are determined using the two ends of the blank stripe connection. As the upper and lower search regions, the sum of the gray values ​​of the left and right search regions and the upper and lower search regions at both ends of the line segment is calculated respectively, and their magnitudes are compared. In the formula, L The length of the luminous surface. W The width of the luminous surface. W O The width of the dark markings along the left and right edges of the blank stripes. L P The length of the dark marker blocks at the top and bottom edges of the blank stripe.

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