A method and system for determining the state of a video data stream

Abstract

The present application belongs to the technical field of electronic rearview mirror, and particularly relates to a video data stream state judgment method and system. The video data stream state judgment method comprises: extracting first frame image data from an image capture module and second frame image data from an image display module at intervals of a preset time; calculating the modified difference value of the color and / or brightness of the first frame image data and the second frame image data; when the modified difference value of at least one of the color and / or brightness is greater than a difference threshold value, then judging that the video data stream state is normal, otherwise, judging that the video data stream state is abnormal. First, the initial difference value of the color and / or brightness of the first frame image data and the second frame image data is calculated, and then by being associated with a vehicle speed correction coefficient, it can be realized that the lower the vehicle speed, the easier it is to meet the difference threshold value, and the higher the vehicle speed, the more difficult it is to meet the difference threshold value, that is, the lower the vehicle speed, the less sensitive the image sticking early warning is, and the higher the vehicle speed, the more sensitive the image sticking early warning is.

Description

Technical Field

[0001] This invention belongs to the field of electronic rearview mirror technology, specifically relating to a method and system for judging the status of video data streams. Background Technology

[0002] With the rapid development of the four new trends in automobiles (intelligentization, connectivity, electrification, and sharing), car designs are becoming increasingly technologically advanced. However, this has led to a problem: drivers cannot clearly see the blind spots behind the vehicle using ordinary side mirrors. This is exacerbated by factors such as passengers or items piled in the front passenger seat, and dark tinted windows, all of which severely impair the driver's ability to observe the rear. This is especially true in extreme conditions such as rain or snow, where the road behind the vehicle becomes virtually invisible. All of these factors have spurred the rapid development of electronic side mirrors.

[0003] Electronic rearview mirrors, also described as CMS or indirect vision devices, are electronic rearview mirror systems composed of components such as high-definition cameras, image sensors, image processors, and displays. Compared to traditional rearview mirrors, electronic exterior rearview mirrors are not only more aerodynamically designed but also offer significant improvements in viewing angle and nighttime visibility. Electronic exterior rearview mirrors provide a more flexible field of view. For drivers, the smaller size of the camera compared to traditional rearview mirrors results in less obstruction of the driver's view. Furthermore, electronic exterior rearview mirrors offer a wider visual coverage, allowing for free switching between wide-angle and telephoto angles. Through system distortion correction, they present a more intuitive and accurate image.

[0004] Therefore, functional safety requirements are crucial for CMS systems, which must respond quickly and accurately to camera, monitor, and control unit failures. In other words, electronic rearview mirror malfunctions can be categorized into three main types: image acquisition device failure, video transmission link failure, and display host image display failure. As an in-vehicle electronic device related to driving safety, it should inform the driver of the device's malfunction status through warning signals when safety-related functions fail.

[0005] When the image acquisition equipment or video transmission link malfunctions, the display host will continue to display the last frame of image data stored in the cache if it does not perform effective detection and judgment. This results in an inability to reflect changes in the vehicle's surrounding environment in real time, a phenomenon known as image lag (or image freezing). Image lag gives the driver a false impression, making it difficult to distinguish between normal and lag images. When obstacles or pedestrians appear around the vehicle, this can potentially lead to serious traffic accidents. Therefore, in terms of consequences, image lag is generally considered more serious than other types of malfunctions. To reduce the driving safety hazards caused by image lag, the electronic rearview mirror host needs to quickly and accurately identify the occurrence of image lag (generally within 400ms) and, within 100ms of detecting the anomaly, provide a warning to the driver through various preset warning signals.

[0006] Chinese patent CN115134590A discloses a method for detecting image lag in electronic rearview mirrors, covering the detection of the image encoding transmission link, data verification of the video data stream, and fault status detection of the display processing module. It can detect whether the video data stream is normal throughout the entire video transmission link, reducing the occurrence of potential accidents. However, this method does not consider the possibility that the selected area may not change color and / or brightness significantly within a short period while the vehicle is stationary, leading the system to misjudge the video stream status as abnormal. Summary of the Invention

[0007] The purpose of this invention is to provide a method and system for determining the status of a video data stream.

[0008] To address the aforementioned technical problems, this invention provides a video data stream status determination method applied to an electronic rearview mirror system, comprising: extracting a first frame of image data from an image capture module and a second frame of image data from an image display module at preset time intervals; calculating a correction difference value for the color and / or brightness of the first frame of image data and the second frame of image data; determining that the video data stream status is normal when the correction difference value for at least one of the color and / or brightness is greater than a difference threshold, otherwise it is abnormal; wherein the method for calculating the correction difference value includes:

[0009] X = W*(1+p);

[0010] p=0.8-v*0.4%, v∈[0,175);

[0011] p = 0.1, v ≥ 175;

[0012] In the formula, X is the correction difference value; W is the initial difference value of color and / or brightness between the first frame image data and the second frame image data; p is the vehicle speed correction coefficient; and v is the real-time vehicle speed in km / h.

[0013] In another aspect, the present invention also provides a video data stream status judgment system, comprising: a first image data sampling module and a second image data sampling module, used to extract a first frame of image data from an image capture module and a second frame of image data from an image display module at preset time intervals; a correction difference value calculation module, used to calculate the correction difference value of color and / or brightness between the first frame of image data and the second frame of image data; and a status judgment module, which determines that the video data stream status is normal when the correction difference value of color or brightness is greater than a difference threshold, otherwise it is abnormal.

[0014] In another aspect, the present invention also provides a method for judging image lag in electronic rearview mirrors, including:

[0015] S1: Determine the working status of the video transmission link and the image display module. If both are normal, proceed to S2; otherwise, proceed to S4.

[0016] S2: Determine the status of the video data stream. If it is normal, proceed to S3; otherwise, proceed to S4.

[0017] S3, determine that the electronic rearview mirror image does not show any lag;

[0018] S4 indicates that the electronic rearview mirror image is experiencing lag; among which...

[0019] The video data stream status determination method described above is used in step S2.

[0020] In another aspect, the present invention also provides an electronic rearview mirror image lag detection device, comprising: a memory and a processor; the processor is used to execute computer instructions stored in the memory to implement the electronic rearview mirror image lag judgment method as described in claim 7.

[0021] In another aspect, the present invention also provides an electronic rearview mirror system, comprising: a camera and a host; wherein the camera includes an image sensing module and an image encoding and transmitting module; and the host includes: an image decoding and receiving module, an image capture module, a data buffer module, an image display module, a first image data sampling module and a second image data sampling module, and a processing module; wherein the image decoding and receiving module is used to decode the encoded image data transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; the image display module is used to display the image data in the data buffer module; the first image data sampling module and the second image data sampling module are used to extract a first frame of image data from the image capture module and a second frame of image data from the image display module respectively at a preset time interval; the processing module is adapted to use the electronic rearview mirror image lag judgment method described above to determine whether the electronic rearview mirror image has a lag phenomenon.

[0022] In another aspect, the present invention also provides a method for calculating image data correction difference values, including:

[0023] X = W*(1+p);

[0024] p=0.8-v*0.4%, v∈[0,175);

[0025] p = 0.1, v ≥ 175;

[0026] In the formula, X is the correction difference value; W is the initial difference value of color and / or brightness between the first frame image data and the second frame image data; p is the vehicle speed correction coefficient; and v is the real-time vehicle speed in km / h.

[0027] The beneficial effect of the present invention is that the video data stream state judgment method of the present invention first calculates the initial difference value of color and / or brightness between the first frame image data and the second frame image data, and then, by associating it with the vehicle speed correction coefficient, it can achieve that the difference threshold is more easily met when the vehicle speed is lower and more difficult to meet the difference threshold when the vehicle speed is higher. That is, the warning of image lag is less sensitive when the vehicle speed is lower and the warning of image lag is more sensitive when the vehicle speed is higher.

[0028] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a flowchart of the video data stream status determination method of the present invention;

[0032] Figure 2 This is a schematic diagram of the electronic rearview mirror system of the present invention;

[0033] Figure 3 This is a schematic diagram of the electronic rearview mirror image lag judgment method of the present invention;

[0034] Figure 4 This is a schematic diagram of a partial image area of ​​the electronic rearview mirror of the present invention;

[0035] Figure 5 This is a schematic diagram of the updated image center according to the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0037] like Figure 2 As shown, in one application scenario, an electronic rearview mirror system may include a camera and a host; wherein the camera includes an image sensing module and an image encoding and transmitting module; and the host includes: an image decoding and receiving module, an image capture module, a data buffer module, an image display module, a first image data sampling module, a second image data sampling module, and a processing module; wherein the image decoding and receiving module is used to decode the encoded image data transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; and the image display module is used to display the image data in the data buffer module.

[0038] like Figure 1As shown, this embodiment provides a video data stream status determination method applied to an electronic rearview mirror system, including: extracting a first frame of image data from an image capture module and a second frame of image data from an image display module at preset time intervals; calculating the color and / or brightness correction difference values ​​between the first frame of image data and the second frame of image data; determining that the video data stream status is normal when the correction difference value of at least one of color and / or brightness is greater than a difference threshold, otherwise it is abnormal; wherein

[0039] The method for calculating the corrected difference value includes:

[0040] X = W*(1+p);

[0041] p=0.8-v*0.4%, v∈[0,175);

[0042] p = 0.1, v ≥ 175;

[0043] In the formula, X is the correction difference value; W is the initial difference value of color and / or brightness between the first frame image data and the second frame image data; p is the vehicle speed correction coefficient; and v is the real-time vehicle speed in km / h.

[0044] In this embodiment, the initial difference value of color and / or brightness between the first frame image data and the second frame image data is first calculated. Then, by associating it with the vehicle speed correction coefficient, it can be realized that the difference threshold is more easily met when the vehicle speed is lower and more difficult to meet when the vehicle speed is higher. That is, the warning of image lag is less sensitive when the vehicle speed is lower and the warning of image lag is more sensitive when the vehicle speed is higher.

[0045] Specifically, when the vehicle is stationary, i.e., at a speed v = 0 km / h, the environmental image of the vehicle does not change much, and the requirements for the normal operation of the rearview mirror are relatively low when the vehicle is stationary. In this case, p is at its maximum, and X is more likely to meet the preset difference threshold, reducing the requirement for the initial difference value W. This can minimize the possibility of false triggering of the system when the vehicle is stationary. When the vehicle is in motion, the requirements for the normal operation of the rearview mirror are relatively high. Theoretically, the normal operation of the rearview mirror system should be guaranteed to ensure driving safety. Therefore, the higher the vehicle speed, the smaller p is, and the less likely X is to meet the preset difference threshold. The more sensitive the image lag warning is, the easier it is to trigger the image lag warning.

[0046] In this embodiment, only the color correction difference value between the first frame image data and the second frame image data can be calculated. If the color correction difference value is greater than the difference threshold, the video data stream status is determined to be normal; otherwise, it is abnormal. Alternatively, only the brightness correction difference value between the first frame image data and the second frame image data can be calculated. If the brightness correction difference value is greater than the difference threshold, the video data stream status is determined to be normal; otherwise, it is abnormal. Alternatively, both the color correction difference value and the brightness correction difference value between the first frame image data and the second frame image data can be calculated simultaneously. If at least one of the two correction difference values ​​is greater than the difference threshold, the video data stream status is determined to be normal; otherwise, it is abnormal.

[0047] In this embodiment, as an optional method for obtaining the initial difference value between two images, a difference hashing algorithm (dhash) can be used to shrink each image to 8×9 pixels, totaling 72 pixels, and then convert the scaled image into a 256-level grayscale image. By calculating the difference between adjacent pixels in each row, if the left pixel is brighter or has a different color than the right pixel, it is recorded as 1; otherwise, it is recorded as 0, forming a total of 64 values, i.e., a 0-1 sequence of length 64, thus obtaining the fingerprint of the corresponding image. Then, the Hamming distance between the corresponding sequences of the two images to be compared is calculated, thus obtaining the initial difference value between the two images. Of course, depending on the specific needs, the initial difference value can also be obtained by multiplying the Hamming distance by an adjustment factor. Those skilled in the art can select the adjustment factor according to actual needs; it can be a constant value, which will not be elaborated here. Compared with other algorithms, dHash is much faster and performs better when the efficiency is almost the same; it is based on gradient implementation.

[0048] In this embodiment, another optional method for obtaining the initial difference value between two images is as follows: For example, when comparing colors, the colors of pixels at the same location in the two image data are compared to determine if they are the same. The number of pixels with different colors is accumulated. After the comparison is completed, the accumulated number is divided by the total number of pixels in the entire image data to obtain the difference percentage, which yields the initial difference value between the two images. Of course, depending on specific needs, the initial difference value can also be obtained by multiplying the difference percentage by an adjustment coefficient. Those skilled in the art can select the adjustment coefficient according to actual needs; it can be a constant value, which will not be elaborated here. The same processing method can be used to compare brightness.

[0049] In this embodiment, preferably, during the process of obtaining the initial difference value, the image area can be reduced to a region close to the middle of the entire image data, which can improve the calculation efficiency and thus determine more quickly whether the electronic rearview mirror image is stuck.

[0050] like Figure 4As shown, in this embodiment, preferably, the initial difference value is the difference value of a local region of the image; the local region of the image is: in the horizontal direction, the region is taken from the center of the image outwards, with a width of 1 / 3 to 1 / 2 of the entire image width; in the vertical direction, the region is taken from the center of the image downwards.

[0051] In the available application scenarios, the central area of ​​the electronic rearview mirror generally covers the main target being photographed, and the main target usually changes. Outside this area, there may be areas such as the ground, vehicle body, and sky that may not change for a long time or change very little, which can easily lead to system misjudgment and mislead users into thinking that the system has experienced image lag. Therefore, selecting a local area of ​​the image to obtain the initial difference value can improve efficiency on the one hand, and improve the authenticity of the difference value on the other hand.

[0052] In one optional application scenario, because users adjust the angle of the electronic rearview mirror, the local area of ​​the image is dynamically changing. Based on the preset image data center, after the user manually adjusts the shooting angle of the electronic rearview mirror, the processor needs to remember the user's operation and update the image data center, that is, update the local area of ​​the image, so that after each adjustment, the initial difference value obtained is for the updated local area of ​​the image.

[0053] Based on this, such as Figure 5 As shown, in this embodiment, before extracting the first frame of image data from the image capture module and the second frame of image data from the image display module, the method further includes updating the image center after the user adjusts the rearview mirror angle.

[0054] In one application scenario, assuming the horizontal viewing angle of the electronic rearview mirror is 76° and the vertical viewing angle is 50°, the initial image data center is 0° (H) and 0° (V). If the user manually adjusts the rearview mirror angle, moving it outward by m° and upward by n°, the image data center dynamically adjusts to m° (H) and n° (V); conversely, if the user moves it inward by m° and downward by n°, the image data center dynamically adjusts to -m° (H) and -n° (V). After updating the image data center, local areas of the image are also updated based on this.

[0055] In this embodiment, preferably, when the user manually adjusts the horizontal and / or vertical angle of the electronic rearview mirror beyond a preset angle threshold, the user is reminded that the rearview mirror position is abnormal and needs to be readjusted.

[0056] In some application scenarios, when users manually adjust the shooting angle of the electronic rearview mirror beyond the preset angle threshold, the local area of ​​the image will cover a large area of ​​the ground, vehicle body, and sky, and the initial difference value will be distorted. Therefore, it is necessary to remind the user to readjust.

[0057] In this embodiment, as an optional implementation of the difference threshold, the difference threshold can be 1.2 times the original difference value; the original difference value can be an initial difference value calculated after sampling the original data as needed during the experiment. Of course, in other embodiments, the difference threshold can be adjusted based on sufficient experimentation to obtain a difference threshold that meets actual needs, or a value can be directly assigned to the difference threshold, which will not be elaborated here.

[0058] Based on the above embodiments, this embodiment also provides a video data stream status judgment system, including: a first image data sampling module and a second image data sampling module, used to extract a first frame of image data from an image capture module and a second frame of image data from an image display module at preset time intervals; a correction difference value calculation module, used to calculate the correction difference value of color and / or brightness between the first frame of image data and the second frame of image data; and a status judgment module, which judges the video data stream status as normal when the correction difference value of color or brightness is greater than a difference threshold, otherwise it is abnormal.

[0059] In this embodiment, the difference value can be corrected using the method described above, which will not be repeated here.

[0060] In this embodiment, the video data stream status determination system further includes: an image center update module, used to update the image center after the user adjusts the rearview mirror angle; the first image data sampling module and the second image data sampling module are adapted to perform sampling after the image center is updated.

[0061] In this embodiment, the video data stream status judgment system may further include a rearview mirror angle judgment module and a reminder module. The rearview mirror angle judgment module can determine whether the horizontal and / or vertical angles of the rearview mirror exceed a preset angle threshold. When the preset angle threshold is exceeded, the reminder module reminds the user to readjust.

[0062] In this embodiment, optionally,

[0063] like Figure 4 As shown, based on the above embodiments, this embodiment provides a method for judging image lag in electronic rearview mirrors, including:

[0064] S1: Determine the working status of the video transmission link and the image display module. If both are normal, proceed to S2; otherwise, proceed to S4.

[0065] S2: Determine the status of the video data stream. If it is normal, proceed to S3; otherwise, proceed to S4.

[0066] S3, determine that the electronic rearview mirror image does not show any lag;

[0067] S4 indicates that the electronic rearview mirror image is experiencing lag; among which...

[0068] The video data stream status determination method described above can be used in S2, and will not be repeated here.

[0069] In this embodiment, the video data stream status, video transmission link operating status, and image display module operating status are prioritized for judgment because the latter two do not require algorithms; they only require active and passive status acquisition by software, which is simple, fast, and effective. Only when the latter two are normal is it necessary to judge the video data stream status. At this point, different time points of the video stream are extracted, and combined with the current vehicle speed information (assuming the CMS system can obtain vehicle speed information), the differences between the extracted image data are compared. Based on the difference results, the normality of the video data stream can be accurately determined. Moreover, during the comparison process, the selected area is generally a small pixel area. Using a difference value hashing algorithm, the accuracy of the judgment can be satisfied while reducing the amount of computation. Furthermore, selecting fewer states for judgment ensures higher processing speed, allowing for timely detection of electronic rearview mirror image lag and reducing potential accident hazards. Additionally, by updating the local image area promptly after the user adjusts the rearview mirror angle, the accuracy of the difference value can be improved.

[0070] In this embodiment, optionally, the working status of the video transmission link includes whether the camera is working properly, whether the image transmission harness is working properly, etc. Normal and abnormal status can be fed back through hardware I / O status. The main control system or processing module can obtain the I / O status in real time through software callbacks, etc., so as to determine the working status of the video transmission link. In order to meet the principle of robustness, it is generally possible to combine the method of actively obtaining I / O status (every time at 200ms interval).

[0071] In this embodiment, optionally, the image display module's operating state is generally the same as the display screen's operating state. Normal and abnormal states can be fed back through the display screen's hardware I / O status. The main control system or processing module can obtain the I / O status in real time through software callbacks or other methods to determine the connection status of the video transmission link. To meet the principle of robustness, a method of actively acquiring I / O status (every time at 200ms intervals) can generally be used.

[0072] Based on the above embodiments, this embodiment also provides an electronic rearview mirror image jamming detection device, including: a memory and a processor; the processor is used to execute computer instructions stored in the memory to implement the electronic rearview mirror image jamming judgment method as described above.

[0073] like Figure 2As shown, based on the above embodiments, this embodiment provides an electronic rearview mirror system, including: a camera and a host; wherein the camera includes an image sensing module and an image encoding and transmitting module; and the host includes: an image decoding and receiving module, an image capture module, a data buffer module, an image display module, a first image data sampling module and a second image data sampling module, and a processing module; wherein the image decoding and receiving module is used to decode the encoded image data transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; the image display module is used to display the image data in the data buffer module and output status feedback information to the main control processing unit; the first image data sampling module and the second image data sampling module are used to extract a first frame of image data from the image capture module and a second frame of image data from the image display module at preset time intervals; the processing module is adapted to use the electronic rearview mirror image lag judgment method described above to determine whether the electronic rearview mirror image has a lag phenomenon.

[0074] In this embodiment, optionally, the first image data sampling module can back up a specified region aera(x,y,w,h) of a frame of video image data from the image capture module to a specified data buffer according to the trigger command of the processing module. Here, x and y represent the starting coordinates of the backup data, w represents the pixel width of the backup data, and h represents the pixel height of the backup data. The second image data sampling module can back up a specified region aera(x,y,w,h) of the current frame of video image data from the image display module to a specified data buffer according to the trigger command of the processing module.

[0075] Based on the above embodiments, this embodiment provides a method for calculating image data correction difference values, including:

[0076] X = W*(1+p);

[0077] p=0.8-v*0.4%, v∈[0,175);

[0078] p = 0.1, v ≥ 175;

[0079] In the formula, X is the correction difference value; W is the initial difference value of color and / or brightness between the first frame image data and the second frame image data; p is the vehicle speed correction coefficient; and v is the real-time vehicle speed in km / h.

[0080] In this embodiment, a warning can be issued to the customer if the electronic rearview mirror image shows lag.

[0081] In summary, the electronic rearview mirror image lag detection method of this invention prioritizes judging the video data stream status, video transmission link operating status, and image display module operating status, as the latter two do not require algorithms and only require active and passive status acquisition by software, making it simple, fast, and effective. Only when the latter two are normal is it necessary to judge the video data stream status. At this point, different time points of the video stream are extracted, combined with the current vehicle speed information (assuming the CMS system can obtain vehicle speed information), to compare the differences between the extracted image data. Based on the difference results, the normality of the video data stream can be accurately determined. Furthermore, during the comparison process, the selected area is generally a small pixel area. Using a difference value hashing algorithm, the accuracy of the judgment can be satisfied while reducing the computational load. In addition, selecting fewer states for judgment ensures high processing speed, enabling timely detection of electronic rearview mirror image lag and reducing potential accident hazards. Moreover, by updating the local image area promptly after the user adjusts the rearview mirror angle, the accuracy of the difference value can be improved.

[0082] In the several embodiments provided in this application, it should be understood that the described apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0083] In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0084] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0085] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for determining the status of a video data stream, applied to an electronic rearview mirror system, characterized in that, The electronic rearview mirror system includes a camera and a main unit; the main unit includes: an image decoding and receiving module, an image capture module, a data buffer module, and an image display module; the image decoding and receiving module is used to decode the encoded image data transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; the image display module is used to display the image data in the data buffer module. The video data stream status determination method includes: At a preset time interval, the first frame of image data is extracted from the image capture module and the second frame of image data is extracted from the image display module simultaneously. Calculate the color and / or brightness correction differences between the first frame image data and the second frame image data; The video data stream is considered normal if the correction difference value for at least one of color and / or brightness is greater than the difference threshold; otherwise, it is considered abnormal. The method for calculating the corrected difference value includes: X = W *(1+ p )； p =0.8- v *0.4%， v ∈[0,175）； p =0.1, v ≥175； In the formula, X To correct for the difference value; W The initial difference in color and / or brightness between the first frame of image data and the second frame of image data; p This is the vehicle speed correction factor; v Real-time vehicle speed, unit: km / h ; The initial difference value is the difference value of a local region of the image; The local image region is defined as follows: in the horizontal direction, the region extending outward from the image center has a width of 1 / 3 to 1 / 2 of the entire image width; in the vertical direction, the region extending downward from the image center has a width of 1 / 3 to 1 / 2 of the entire image width.

2. The video data stream status determination method as described in claim 1, characterized in that, The camera includes an image sensing module and an image encoding and transmission module.

3. The video data stream status determination method as described in claim 1, characterized in that, Before extracting the first frame of image data from the image capture module and the second frame of image data from the image display module, the following steps are also included: The image center is updated after the user adjusts the rearview mirror angle.

4. A video data stream status determination system, applied to an electronic rearview mirror system, characterized in that, The electronic rearview mirror system includes a camera and a main unit; the main unit includes: an image decoding and receiving module, an image capture module, a data buffer module, and an image display module; the image decoding and receiving module is used to decode the encoded image data transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; the image display module is used to display the image data in the data buffer module. The video data stream status determination system includes: The first image data sampling module and the second image data sampling module are used to simultaneously extract the first frame of image data from the image capture module and the second frame of image data from the image display module at a preset time interval. The correction difference calculation module is used to calculate the correction difference value of color and / or brightness between the first frame image data and the second frame image data; The status determination module determines the video data stream status as normal if the color or brightness correction difference value is greater than the difference threshold; otherwise, it determines it as abnormal. The method for calculating the corrected difference value includes: X = W *(1+ p )； p =0.8- v *0.4%， v ∈[0,175）； p =0.1, v ≥175； In the formula, X To correct for the difference value; W The initial difference in color and / or brightness between the first frame of image data and the second frame of image data; p This is the vehicle speed correction factor; v Real-time vehicle speed, unit: km / h； The initial difference value is the difference value of a local region of the image; The local image region is defined as follows: in the horizontal direction, the region extending outward from the image center has a width of 1 / 3 to 1 / 2 of the entire image width; in the vertical direction, the region extending downward from the image center has a width of 1 / 3 to 1 / 2 of the entire image width.

5. The video data stream status determination system as described in claim 4, characterized in that, Also includes: The image center update module is used to update the image center after the user adjusts the rearview mirror angle; The first image data sampling module and the second image data sampling module are adapted to perform sampling after the image center is updated.

6. A method for judging image lag in an electronic rearview mirror, characterized in that, include: S 1. Determine the working status of the video transmission link and the image display module. If both are normal, then proceed. S 2; otherwise, execute. S 4; S 2. Determine the status of the video data stream. If it is normal, then execute... S 3; otherwise ,implement S 4; S 3. Determine that the electronic rearview mirror image does not show any lag or stuttering. S 4. Determine if the electronic rearview mirror image is stuck; in The S The video data stream status is determined using the video data stream status determination method as described in any one of claims 1 to 3 in step 2.

7. An electronic rearview mirror image lag detection device, characterized in that, include: Memory and processor; The processor is used to execute computer instructions stored in the memory to implement the electronic rearview mirror image lag judgment method as described in claim 6.

8. An electronic rearview mirror system, characterized in that, include: Camera and main unit; in The camera includes an image sensing module and an image encoding and transmission module; as well as The host computer includes: an image decoding and receiving module, an image capture module, a data buffer module, an image display module, a first image data sampling module, a second image data sampling module, and a processing module; wherein... The image decoding receiving module is used to decode the image data in the encoded format transmitted by the camera and output it to the image capture module; The image capture module is used to output the received image data to the data buffer module; The image display module is used to display and output the image data in the data buffer module; The first image data sampling module and the second image data sampling module are used to simultaneously extract the first frame of image data from the image capture module and the second frame of image data from the image display module at a preset time interval. The processing module is adapted to use the electronic rearview mirror image lag judgment method as described in claim 6 to determine whether the electronic rearview mirror image is lag-prone.

9. A method for calculating image data correction difference values, characterized in that, include: X = W *(1+ p )； p =0.8- v *0.4%， v ∈[0,175）； p =0.1, v ≥175； In the formula, X To correct for the difference value; W The initial difference in color and / or brightness between the first frame of image data and the second frame of image data; p This is the vehicle speed correction factor; v Real-time vehicle speed, unit: km / h ; The first frame of image data and the second frame of image data are simultaneously extracted from the image capture module and the image display module of the host of the electronic rearview mirror system at a preset time interval; the host includes: an image decoding and receiving module, an image capture module, a data buffer module and an image display module; The image decoding receiving module is used to decode the image data in the encoded format transmitted by the camera and output it to the image capture module; the image capture module is used to output the received image data to the data buffer module; the image display module is used to display the image data in the data buffer module. The initial difference value is the difference value of a local region of the image; the local region of the image is: in the horizontal direction, the region is taken from the center of the image outwards, with a width of 1 / 3 to 1 / 2 of the entire image width; in the vertical direction, the region is taken from the center of the image downwards.

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