Electrochromic glare sensor value algorithm based on post-pull camera exposure parameters

Abstract

This invention discloses an electrochromic control algorithm based on the exposure parameters of a rear-view camera, which includes the following steps: (1) reading the EV value of the rear-view camera, dividing the image acquired by the rear-view camera into M×N two-dimensional blocks, and calculating the glare value of each block; (2) constructing an M×N internal rearview mirror masking matrix W. inside External left rearview mirror mask matrix W left External right-side rearview mirror mask matrix W righ Masking matrix W inside W left W righ The element is 0 or 1, where 1 represents the area where the inner rearview mirror, the outer left rearview mirror, and the outer right rearview mirror are located in the image captured by the rear camera; (3) Calculate the glare sensing values ​​of the inner rearview mirror, the outer left rearview mirror, and the outer right rearview mirror respectively; This invention replaces the glare sensor and calculates the glare sensing values ​​of the inner and outer three rearview mirrors according to the algorithm, and performs independent anti-glare function for the inner and outer three EC mirrors, which can effectively reflect the scene of the outer left and right EC mirrors.

Description

Technical Field

[0001] This invention relates to an electrochromic control algorithm based on the shooting parameters and pixel brightness values ​​of a rear-view camera, belonging to the field of automotive rearview mirror control technology. Background Technology

[0002] like Figure 1-2 As shown, the current solution for anti-glare control of internal and external EC (Electro-Chromic) mirrors in streaming media systems is as follows: A rearview mirror photochromic system is combined with a camera and a display screen. The rearview mirror photochromic system uses an internal ambient light sensor (ALS) and an anti-glare sensor (GLS) to synchronously control the anti-glare function of the internal and external electro-chromic (EC) anti-glare mirrors. Examples include the vehicle rearview mirror system disclosed in US Patent Publication No. US2013048835A1 and the drive circuit of an optoelectronic rearview mirror system disclosed in Chinese Patent Publication No. CN104968522B. Such streaming media systems include... Figure 2 , Figure 2 The dashed squares represent the internal functional components. The system comprises three main parts: the streaming media unit, external left and right side EC mirrors, and a rear-mounted camera. Specific hardware details are as follows... Figure 3 As shown, the functions are as follows:

[0003] The streaming media unit is the most important part of the system, including ALS, GLS, EC control circuit, internal EC, display screen and control calculation module. Its operation is as follows: (1) The control calculation module receives the output of ALS and GLS, performs calculations based on the received data, and sends control signals to EC control circuit, while controlling the color-changing function of internal electro-optical element and external electro-optical element. (2) The image data of the rear camera is transmitted to the control calculation module and controlled by it. The control calculation module processes the image data appropriately and displays it on the screen. (3) Among them, GLS detects glare from the rear. Since the middle is the display screen, it is usually installed below and above the rear of the internal rearview mirror.

[0004] External left and right EC mirrors: The two rearview mirrors on the left and right sides contain EC control receivers, which control the color change of the external left and right EC mirrors according to the received control signals.

[0005] Rear-view camera: A camera that transmits images and receives streaming media to control the image sensor, such as resolution, exposure value, and signal gain, etc. In order to make the image the same as the image in the rearview mirror, the output image of the rear-view camera needs to be mirrored.

[0006] The above-mentioned system's synchronous anti-glare control for the three internal and external EC mirrors cannot effectively reflect the scene of the external left, external right, and internal EC mirrors. For example, when the external left EC mirror has strong glare, the GLS of the internal EC mirror does not receive the glare (the glare sensor is used to detect the brightness of glare coming from behind, and since the center is a display screen, it is usually installed above or below the interior rearview mirror), and the GLS cannot effectively reflect the scene of the external left EC mirror. Summary of the Invention

[0007] The purpose of this invention is to provide an electrochromic glare sensing algorithm based on the exposure parameters of a rear-mounted camera. Based on the existing rear-mounted camera, the algorithm calculates and replaces the traditional glare sensor element, realizing independent control of the inner and outer EC lenses.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows:

[0009] The electrochromic glare sensor algorithm based on the exposure parameters of the rear-view camera includes the following steps:

[0010] (1) Read the EV (Exposure Value) value of the rear camera, divide the image captured by the rear camera into M×N 2D (two-dimensional) blocks, and calculate the glare value of each block. The calculation formula is as follows:

[0011]

[0012] Y i,,j P represents the glare value of the block in column i and row j. `avg()` is the average function: it sums the brightness of all pixels within the block and then divides by the total number of pixels in the block to obtain the average brightness of all pixels within the block. l,m The value represents the pixel brightness within the block, where l is the vertical coordinate, m is the horizontal coordinate, and B... H B V These represent the number of vertical and horizontal pixels contained in each square, where M and N are positive integers.

[0013] (2) Construct an M×N internal rearview mirror masking matrix W inside External left rearview mirror mask matrix W left External right-side rearview mirror mask matrix W righ Masking matrix W inside W left W righ The element is 0 or 1, where 1 represents the area where the inner rearview mirror, the outer left rearview mirror, and the outer right rearview mirror are located in the image captured by the rear camera.

[0014] (3) Based on the masking matrix constructed in step (2), calculate the glare sensing values ​​of the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror respectively. The calculation formula is as follows:

[0015]

[0016] Among them W k Let k be the selected M×N masking matrix, where k is one of the interior rearview mirror, the exterior left rearview mirror, and the exterior right rearview mirror. The element in the i-th column and j-th row of the selected masking matrix.

[0017] After the glare sensor value is obtained, the ambient light sensor signal and the three glare sensor values ​​(simulated glare control values) are transmitted to the main control arithmetic unit, which are used to generate voltage control signals to independently control the anti-glare of the three internal and external EC mirrors.

[0018] This invention utilizes the glare sensor values ​​(values ​​from the inner and outer rearview mirrors) to provide independent anti-glare functions for the three EC mirrors, effectively reflecting the scene reflected in the outer left and right EC mirrors. The algorithm of this invention replaces the glare sensor, reduces the number of front-view GLS components, resulting in a simpler appearance and easier structural design, making it particularly suitable for narrow-bezel screen designs. Attached Figure Description

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] Figure 1 This is a diagram of a vehicle's rearview mirror.

[0021] Figure 2 This is a block diagram of a rearview mirror system.

[0022] Figure 3 This is a schematic diagram of the appearance of a streaming media system.

[0023] Figure 4 This is a schematic diagram of a streaming media system circuit.

[0024] Figure 5 This diagram illustrates the independent anti-glare control of the three internal and external EC mirrors using the algorithm of this invention.

[0025] Figure 6 The anti-glare values ​​for the three rearview mirrors are shown in the graph.

[0026] Figure 7 Before and after comparison images for improvement.

[0027] Figure 8 The rear camera image of 1910×1080 pixels is divided into 9×5 2D glare blocks.

[0028] Figure 9The algorithm of this invention is used to calculate the glare control value.

[0029] Figure 10 This is a masking matrix diagram. Detailed Implementation

[0030] An electrochromic control algorithm based on the exposure parameters of the rear-view camera, combined with... Figure 4-10 As shown, it includes the following steps:

[0031] (1) Read the EV value of the rear camera (1920×1080 pixels) and perform 9×5 two-dimensional block segmentation on the image captured by the rear camera. The central 5×3 block is 200×200 pixels in size. Figure 8 As shown, the glare value for each block is calculated using the following formula:

[0032] Specific calculations are as follows: Figure 9 As shown.

[0033] Here, avg() is the average function: it sums up the brightness of all pixels in the block and then divides it by the total number of pixels in the block to obtain the average brightness of all pixels in the block, which is used as the glare value of the block.

[0034] P l,m The value represents the pixel brightness within the block, where l is the vertical coordinate, m is the horizontal coordinate, and B... H and B V These represent the number of vertical and horizontal pixels contained in each square.

[0035] (2) Figure 10 As shown, an M×N internal rearview mirror masking matrix W is constructed. inside External left rearview mirror mask matrix W left External right-side rearview mirror mask matrix W righ Masking matrix W inside W left W righ The element is either 0 or 1, where 1 represents the area occupied by the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror in the image captured by the rear-mounted camera. In other words, the area occupied by the rearview mirror in the image captured by the rear-mounted camera is 1, and other areas are 0. For example... Figure 6 As shown. Because rearview mirrors from different manufacturers vary in size, the area where the rearview mirror is located in the image captured by the rear-view camera is different, therefore the masking matrix of the rearview mirrors from different manufacturers is different.

[0036] (3) Based on the masking matrix constructed in step (2), calculate the glare sensing values ​​of the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror respectively. The calculation formula is as follows:

[0037]

[0038] Among them W k Let k be the selected M×N masking matrix, where k is one of the interior rearview mirror, the exterior left rearview mirror, and the exterior right rearview mirror. The element in the i-th column and j-th row of the selected masking matrix.

[0039] For example, when calculating the glare sensor value of the interior rearview mirror, W k For the interior rearview mirror mask matrix W inside , for W inside At the positions in the matrix where the element is 1, perform a cumulative calculation of the glare value for the block. For the interior rearview mirror mask matrix W inside The element in the i-th column and j-th row. The specific calculation is as follows: Figure 9 As shown.

[0040] like Figure 4 As shown, after the signal from the rear-mounted camera is transmitted to the main control processor, three glare sensor values ​​are obtained through the aforementioned algorithm (evGLS algorithm). The main control processor responds to the ambient light sensor and the three glare sensor values ​​(simulated glare control values), generating voltage control signals respectively. These signals, through the drive circuit, independently control the anti-glare function of the three internal and external EC mirrors (i.e., the internal EC mirror, the external left EC mirror, and the external right EC mirror). The process is as follows: Figure 5 As shown.

[0041] like Figure 7 As shown, the three EC lenses (inner and outer) are simultaneously anti-glare, and all three lenses are simultaneously completely darkened, while the left outer lens is not visible (e.g.). Figure 7 (Left side). The three lenses have independent anti-glare mechanisms, and the left outer lens still maintains a clear field of view (e.g., Figure 7 (Right side)

[0042] The above embodiments do not limit the present invention in any way. All technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. An algorithm for electrochromic glare sensing values ​​based on the exposure parameters of a rear-view camera, characterized in that... Includes the following steps: (1) Read the EV value of the rear camera, divide the image captured by the rear camera into two-dimensional blocks of M×N, and calculate the glare value of each block. The calculation formula is as follows: Among them, Y i,j Let P be the glare value of the block in the i-th column and j-th row, avg() be the average function, and P be the glare value. l,m The value represents the brightness of the pixels within the block, where l is the vertical coordinate, m is the horizontal coordinate, and B... H B V These represent the number of vertical and horizontal pixels contained in each block, respectively, where M and N are positive integers; (2) Construct an M×N internal rearview mirror masking matrix W inside External left rearview mirror mask matrix W left External right-side rearview mirror mask matrix W right Interior rearview mirror shield matrix W inside External left rearview mirror mask matrix W left External right-side rearview mirror mask matrix W right The element is 0 or 1, where 1 represents the area where the inner rearview mirror, the outer left rearview mirror, and the outer right rearview mirror are located in the image captured by the rear camera. (3) Based on the masking matrix constructed in step (2), calculate the glare sensing values ​​of the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror respectively. The calculation formula is as follows: Among them W k Let k be the selected M×N masking matrix, where k is one of the interior rearview mirror, the exterior left rearview mirror, and the exterior right rearview mirror. The element in the i-th column and j-th row of the selected masking matrix; After the signal from the rear-view camera is transmitted to the main control unit, the glare sensing values ​​of the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror are obtained through the electrochromic glare sensing value algorithm based on the exposure parameters of the rear-view camera. The main control unit responds to the ambient light sensor and the glare sensing values ​​of the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror, and generates voltage control signals respectively. Through the drive circuit, the interior rearview mirror, the left exterior rearview mirror, and the right exterior rearview mirror are independently controlled for anti-glare function.

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