Rendering method and system suitable for vehicle-mounted electronic map and medium

Abstract

The invention relates to the field of image processing, in particular to a rendering method and system suitable for a vehicle-mounted electronic map and a medium, and the method comprises the steps: obtaining a driving speed and latitude and longitude coordinates in a vehicle driving process; determining a first access criticality of an area corresponding to each latitude and longitude coordinate in each complete driving period according to the driving speed; according to the first access criticality in all the complete driving cycles under each complete running path, obtaining a second access criticality of an area corresponding to each latitude and longitude coordinate under each complete running path; determining a third access criticality of each area according to all the second access criticality of the same area; according to the third access criticality of each area, determining a preloading sequence and a preloading strategy of each area; and rendering at least partial areas in the vehicle-mounted electronic map according to the preloading sequence and the preloading strategy. According to the scheme provided by the invention, the loading adaptability and the loading accuracy of the vehicle-mounted electronic map are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of image processing, and in particular to a rendering method, system and medium suitable for vehicle-mounted electronic maps. Background Art

[0002] The vehicle electronic map is the core component of the intelligent navigation system, and its rendering technology directly determines the user experience and system performance. As the vehicle navigation system develops towards intelligence, real-time and high-precision, the vehicle electronic map needs to integrate multi-source data and achieve fast loading, dynamic updating and smooth display on the embedded hardware platform through efficient rendering methods.

[0003] In the related art, during the rendering process of the vehicle-mounted electronic map, preloading technology is usually used to load data. Since the preloading link is usually based on a fixed radius or a preset path, it cannot adapt to the changing needs of dynamic navigation, and the map area is equalized, resulting in insufficient data loading in key areas.

[0004] Therefore, the rendering scheme of the traditional vehicle-mounted electronic map has the problems of insufficient data loading, low loading accuracy and poor adaptability. Summary of the invention

[0005] In order to solve the technical problems of insufficient data loading, low loading accuracy and poor adaptability of traditional vehicle-mounted electronic map rendering solutions, the purpose of the present invention is to provide a rendering method, system and medium suitable for vehicle-mounted electronic maps with better loading effect and strong adaptability. The technical solutions adopted are as follows: In one aspect, the present invention provides a rendering method applicable to an in-vehicle electronic map, the method comprising: Obtain the vehicle's driving speed and longitude and latitude coordinates during driving; Determining the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed; According to the first access criticality in all complete driving cycles under each complete operation path, the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path is calculated; Determine the third access criticality of each area in the vehicle-mounted electronic map according to all the second access criticalities corresponding to the same area; Determine the preloading order and preloading strategy of each area according to the third access criticality of each area; According to the preloading sequence and the preloading strategy, at least a part of the area in the vehicle-mounted electronic map is rendered.

[0006] According to a rendering method for an in-vehicle electronic map provided by the present invention, the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle is determined according to the driving speed, including: Determine the occurrence frequency value of each latitude and longitude coordinate of the vehicle in each complete driving cycle; According to the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated.

[0007] According to a rendering method applicable to an in-vehicle electronic map provided by the present invention, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated based on the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, including: The frequency of occurrence of each longitude and latitude coordinate is divided by the sum of the vehicle's speed at the time of collection of each longitude and latitude coordinate and a preset non-zero constant value to obtain a user attention ratio; The user attention ratio is normalized to obtain the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle.

[0008] According to a rendering method applicable to an in-vehicle electronic map provided by the present invention, a second access criticality of each area corresponding to each longitude and latitude coordinate under each complete running path is calculated based on the first access criticality in all complete driving cycles under each complete running path, including: The first access criticality in all complete driving cycles under each complete operation path is averaged to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path.

[0009] According to a rendering method applicable to an in-vehicle electronic map provided by the present invention, a preloading order and a preloading strategy of each area are determined according to the third access criticality of each area, including: Calculate the access weight value of each area according to the third access criticality of each area; According to the access weight value, determine the preloading order and data loading queue corresponding to each area in the vehicle electronic map; A preloading strategy for each area is determined according to the data loading queue.

[0010] According to a rendering method applicable to an in-vehicle electronic map provided by the present invention, the data loading queue includes a priority loading queue and a subsequent loading queue; According to the access weight value, determining the preloading order and data loading queue corresponding to each area in the vehicle electronic map includes: Determine the preloading order corresponding to each area in the vehicle-mounted electronic map according to the order of the access weight values ​​from large to small; Compare the access weight value of each area with the preset weight threshold to obtain a comparison result; The data corresponding to the area whose access weight value is higher than the preset weight threshold according to the comparison result is divided into a priority loading queue; The data corresponding to the area whose comparison result is that the access weight value is less than or equal to the preset weight threshold is divided into a subsequent loading queue.

[0011] According to a rendering method applicable to an in-vehicle electronic map provided by the present invention, a preloading strategy for each area is determined according to the data loading queue, including: When the user does not issue an active update instruction and the vehicle does not travel to any area in the subsequent loading queue, the preloading strategy is determined to be the first loading strategy; the first loading strategy includes: loading detailed map data in the area in the priority loading queue, and loading basic map contour data in the area in the subsequent loading queue; When the user does not issue an active update instruction and the vehicle travels to any area in the subsequent loading queue, the preloading strategy is determined to be the second loading strategy; the second loading strategy includes: determining the data importance of each sub-data in the detailed map data in each area in the subsequent loading queue; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the vehicle-mounted electronic map, and setting the corresponding distance thresholds according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold; When the user issues an active update instruction, the preloading strategy is determined to be the third loading strategy; the third loading strategy includes: determining the abnormality corresponding to the vehicle's driving speed, and determining the user's instruction intention based on the abnormality; setting the data importance of some sub-data in the detailed map data in each area in the subsequent loading queue based on the user's instruction intention; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map, and setting the corresponding distance thresholds according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold.

[0012] According to a rendering method applicable to an on-vehicle electronic map provided by the present invention, determining the abnormality corresponding to the driving speed of the vehicle includes: Get the average speed of the vehicle when it is running normally; Subtract the driving speed from the speed average to obtain a speed difference; Divide the speed mean by 2 to obtain a speed comparison value; Subtract the speed difference from the speed comparison value to obtain a speed intermediate value; The intermediate speed value is input into the sign function to obtain the abnormality corresponding to the vehicle's running speed.

[0013] On the other hand, the present invention further provides a rendering system suitable for an in-vehicle electronic map, the system comprising: An acquisition module is used to acquire the driving speed and longitude and latitude coordinates of the vehicle during driving; A first processing module, used for determining, according to the driving speed, a first access criticality of an area corresponding to each longitude and latitude coordinate in each complete driving cycle; The second processing module is used to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path according to the first access criticality in all complete driving cycles under each complete operation path; A third processing module, for determining the third access criticality of each area in the vehicle-mounted electronic map according to all second access criticalities corresponding to the same area; A fourth processing module, used for determining a preloading order and a preloading strategy for each area according to the third access criticality of each area; The rendering module is used to render at least a part of the area in the vehicle-mounted electronic map according to the preloading sequence and the preloading strategy.

[0014] On the other hand, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements any of the above-mentioned rendering methods applicable to vehicle-mounted electronic maps.

[0015] The present invention has the following beneficial effects: The first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle is determined by the driving speed, and the second access criticality of each area corresponding to each longitude and latitude coordinate in each complete running path is calculated based on the first access criticality in all complete driving cycles under each complete running path, and the third access criticality of each area in the vehicle-mounted electronic map is determined based on all the second access criticalities corresponding to the same area, and the preloading order and preloading strategy of each area are determined based on the third access criticality of each area, and finally, at least part of the area in the vehicle-mounted electronic map is rendered according to the preloading order and preloading strategy. The scheme provided by the present invention can optimize the preloading order and preloading strategy of different areas in the vehicle-mounted electronic map according to the real-time behavior of the vehicle, so as to adapt to the changes in the demand for dynamic navigation, realize the full loading of key area data, and improve the loading adaptability and loading accuracy of the vehicle-mounted electronic map. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A method flow chart of a rendering method applicable to a vehicle-mounted electronic map provided by an embodiment of the present invention; Figure 2 A system structure diagram of a rendering system suitable for an in-vehicle electronic map provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a rendering method, system and medium suitable for vehicle-mounted electronic maps proposed by the present invention, its specific implementation, structure, features and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0019] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0020] A specific scheme of a rendering method, system and medium applicable to an in-vehicle electronic map provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0021] See also Figure 1 , which shows a method flow chart of a rendering method suitable for a vehicle-mounted electronic map provided by an embodiment of the present invention, such as Figure 1 As shown, the above rendering method applicable to the vehicle-mounted electronic map mainly includes the following steps: Step 110: Obtain the driving speed and longitude and latitude coordinates of the vehicle during driving.

[0022] In practical applications, after the vehicle is started or the vehicle electronic system is started, the vehicle speed and latitude and longitude coordinates can be obtained through the vehicle sensors during the driving process. The vehicle speed includes information such as vehicle speed, acceleration and driving direction. The vehicle sensors include GPS modules, gyroscopes and accelerometers. The data collected by these sensors can be transmitted to the execution subject of this method (such as the data collection and analysis module in a computer or server) through the vehicle bus, and these data can be stored in the local database. In the actual processing stage, the data collected by the above sensors can be counted every 10 seconds.

[0023] Step 120: Determine the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed.

[0024] It can be understood that the first access criticality can represent the importance of the area corresponding to each longitude and latitude coordinate in each complete driving cycle, that is, the degree of user attention. The larger the first access criticality, the higher the degree of user attention.

[0025] Step 130: Calculate the second access criticality of each area corresponding to each longitude and latitude coordinate in each complete operation path according to the first access criticality in all complete driving cycles in each complete operation path.

[0026] It can be understood that the second access criticality can represent the importance of each area corresponding to the longitude and latitude coordinates in all complete driving cycles under each complete operating path. The higher the second access criticality, the more important the area corresponding to the longitude and latitude coordinates under the complete operating path.

[0027] Step 140: Determine the third access criticality of each area in the vehicle-mounted electronic map according to all the second access criticalities corresponding to the same area.

[0028] It can be understood that the third access criticality can represent the user's attention level to each area in the vehicle-mounted electronic map. The higher the third access criticality, the higher the user's attention to the area, and the more important the area is.

[0029] Step 150: Determine the preloading order and preloading strategy of each region according to the third access criticality of each region.

[0030] It should be noted that the preloading order and preloading strategy of each area in the present embodiment are obtained based on the third access criticality which can comprehensively characterize the user's attention degree to the area. At this time, the preloading order and preloading strategy of each area can adapt to the actual behavior of the vehicle. Therefore, the preloading order and preloading strategy have a higher reference value.

[0031] Step 160: Render at least a portion of the vehicle-mounted electronic map according to the preloading sequence and preloading strategy.

[0032] In the solution provided by this embodiment, since the preloading order and preloading strategy are determined based on a series of calculated third access criticalities, the key areas in the vehicle electronic map can be fully loaded according to user needs, thereby improving the rendering effect of the vehicle electronic map.

[0033] In one embodiment, determining the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed specifically includes: First, the occurrence frequency value of each latitude and longitude coordinate of the vehicle in each complete driving cycle is determined.

[0034] It is understandable that since each vehicle frequently visits different places, each vehicle has different access frequencies to different areas in the vehicle-mounted electronic map. This embodiment determines the occurrence frequency values ​​of each latitude and longitude coordinate in different areas through changes in vehicle location information stored in the local database.

[0035] Since the operation of the vehicle is a continuous process, the position change of the vehicle in each complete driving cycle (i.e., from vehicle startup to vehicle shutdown) can be obtained from the local database. Assume that a total of M complete driving cycles are obtained. Assume that a total of W longitude and latitude coordinates are obtained in M ​​complete driving cycles. Among them, when the distance between two longitude and latitude coordinates is less than 1.2 meters, they are usually regarded as the same position, and then the occurrence frequency value of each longitude and latitude coordinate can be counted.

[0036] Since the starting position and the shutdown position of the vehicle in each complete driving cycle are places where the driver needs to stay for a long time, the longitude and latitude coordinates corresponding to the starting position and the shutdown position of the vehicle are very important in the on-board electronic map. In this embodiment, the occurrence frequency values ​​of the longitude and latitude coordinates corresponding to the starting position and the shutdown position of the vehicle are doubled, for example, they can be multiplied by 3 to achieve triple processing.

[0037] According to the above statistical scheme, the occurrence frequency value of each latitude and longitude coordinate of the vehicle in each complete driving cycle can be obtained.

[0038] Then, according to the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated.

[0039] In practical applications, taking the mth complete driving cycle as an example, by analyzing the changes in the vehicle's driving speed, the first access criticality of the area corresponding to each longitude and latitude coordinate can be determined. Specifically, the greater the occurrence frequency value of the i-th longitude and latitude coordinate of the vehicle and the smaller the vehicle's driving speed, it means that there may be traffic congestion near the i-th longitude and latitude coordinate, or the i-th longitude and latitude coordinate may be an area of ​​concern to the user, which means that the first access criticality of the area corresponding to the i-th longitude and latitude coordinate is greater.

[0040] In one embodiment, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated based on the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, including: First, the frequency of occurrence of each longitude and latitude coordinate is divided by the sum of the vehicle's speed at the time of collection of each longitude and latitude coordinate and a preset non-zero constant to obtain the user attention ratio.

[0041] Then, the user attention ratio is normalized to obtain the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle.

[0042] In this embodiment, the mathematical expression of the first access criticality of the area corresponding to the i-th longitude and latitude coordinates in the m-th complete driving cycle is as follows: (1) In the formula, Indicates the first access criticality of the area corresponding to the i-th longitude and latitude coordinates in the m-th complete driving cycle, represents the normalization function, represents the frequency of occurrence of the i-th longitude and latitude coordinates in the m-th complete driving cycle, represents the driving speed corresponding to the collection time of the i-th longitude and latitude coordinates in the m-th complete driving cycle, represents the user attention ratio, Indicates a preset non-zero value to avoid the denominator being zero.

[0043] In one embodiment, according to the first access criticality in all complete driving cycles under each complete running path, the second access criticality of each area corresponding to the longitude and latitude coordinates under each complete running path is calculated, specifically including: The first access criticality in all complete driving cycles under each complete operation path is averaged to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path.

[0044] It can be understood that since the same complete operating path may be completely traveled by the vehicle multiple times, the second access criticality of each area corresponding to the longitude and latitude coordinates under the same complete operating path can be determined by analyzing the first access criticality of the area corresponding to each longitude and latitude coordinates in all complete driving cycles under the same complete operating path.

[0045] In this embodiment, it is assumed that there are N complete running paths, each of which has S complete driving cycles. The second access criticality of the area corresponding to the j-th longitude and latitude coordinates in the n-th complete running path can be specifically expressed as follows: (2) In the formula, Indicates the second access criticality of the area corresponding to the jth longitude and latitude coordinates under the nth complete running path. represents the first access criticality of the area corresponding to the jth longitude and latitude coordinates in the sth complete driving cycle, where: .

[0046] Subsequently, the second access criticality corresponding to each longitude and latitude coordinate under each complete running path can be classified according to the corresponding area, and the second access criticality for the same area can be divided into the same group to obtain all the second access criticality corresponding to each area. Then, the average of all the second access criticality corresponding to each area can be calculated to obtain the third access criticality of each area.

[0047] In practical applications, since some areas in the vehicle electronic map are not visited by the user, this embodiment records the third access criticality of these areas that the user has not visited as the minimum value of all third access criticalities. Thus, the third access criticality of each area in the vehicle electronic map can be obtained.

[0048] In one embodiment, the preloading order and preloading strategy of each region are determined according to the third access criticality of each region, specifically including: First, the access weight value of each area is calculated according to the third access criticality of each area.

[0049] In this embodiment, the access weight value of the kth area in the vehicle-mounted electronic map can be specifically expressed as follows: (3) In the formula, Indicates the access weight value of the kth block area, represents the third access criticality of the k-th block area, Indicates The third access criticality of the block region, where , Indicates the total number of areas in the vehicle electronic map.

[0050] Then, according to the access weight value, the preloading order and data loading queue corresponding to each area in the vehicle-mounted electronic map are determined.

[0051] In this embodiment, the data loading queue specifically includes a priority loading queue and a subsequent loading queue.

[0052] Exemplarily, according to the access weight value, determining the preloading order and data loading queue corresponding to each area in the vehicle-mounted electronic map specifically includes: First, the preloading order corresponding to each area in the vehicle-mounted electronic map is determined according to the order of access weight values ​​from large to small.

[0053] In this embodiment, the regions in the vehicle-mounted electronic map may be sorted in descending order of access weight values, thereby obtaining a preloading order corresponding to the regions in the vehicle-mounted electronic map.

[0054] Then, the access weight value of each area is compared with the preset weight threshold to obtain a comparison result.

[0055] On the one hand, the data corresponding to the area whose access weight value is higher than the preset weight threshold as a comparison result is divided into a priority loading queue.

[0056] On the other hand, the data corresponding to the area whose comparison result is that the access weight value is less than or equal to the preset weight threshold is divided into a subsequent loading queue.

[0057] In this embodiment, in the process of pre-loading and sorting each area in the vehicle map according to the access weight value, the data to be loaded in the area with a larger access weight value is placed in the priority loading queue, and the data to be loaded in the area with a smaller access weight value is placed in the subsequent loading queue.

[0058] In practical applications, the preset weight threshold may be determined according to the maximum and minimum values ​​of the access weight value, and specifically, may be the average value of the maximum and minimum values ​​of the access weight value.

[0059] Finally, the preloading strategy for each area is determined based on the data loading queue.

[0060] In a specific implementation, the preloading strategy for each area is determined according to the data loading queue, including: On the one hand, when the user does not issue an active update instruction and the vehicle does not travel to any area in the subsequent loading queue, the preloading strategy is determined to be the first loading strategy; the first loading strategy includes: loading detailed map data in the area in the priority loading queue, and loading basic map outline data in the area in the subsequent loading queue.

[0061] In this embodiment, the detailed map data specifically includes high-precision information such as the curvature and slope of the road, vehicle information, three-dimensional model data of buildings, etc. The basic map outline data includes the main outline and the location of important landmarks.

[0062] On the second aspect, when the user does not issue an active update instruction and the vehicle travels to any area in the subsequent loading queue, the preloading strategy is determined to be the second loading strategy; the second loading strategy includes: determining the data importance of each sub-data in the detailed map data in each area in the subsequent loading queue; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map, and setting the corresponding distance thresholds according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold.

[0063] In practical applications, the data importance of each sub-data can be determined from the perspective of the real-time performance of each sub-data. For example, the actual time difference between the collection time of each sub-data and the current time can be calculated, and the ratio between the actual time difference and the reference time difference can be used as the data importance.

[0064] In this embodiment, when the vehicle gradually drives to any area in the subsequent loading queue, the loading strategy can be dynamically adjusted, which can be implemented by the second loading strategy. Among them, the distance value between the theoretical position and the actual position of each sub-data in each area can be calculated using the Euclidean distance calculation method. Assuming that there are R sub-data that need to be loaded, R distance thresholds can be set in descending order of data importance. When the calculated distance value is greater than the corresponding distance threshold, the corresponding sub-data is loaded. It should be noted that sub-data refers to high-precision data.

[0065] In some embodiments, for the case where the sub-data is road curvature or road slope, the actual position of the sub-data can be understood as the position of the data point corresponding to the measured value of the sub-data, and the theoretical position of the sub-data can be understood as the position of the data point corresponding to the theoretical value of the sub-data. If in actual application, taking road curvature as an example, the shortest path from the position of the data point corresponding to the measured value of the curvature to the position of the data point corresponding to the theoretical value of the curvature can be determined through a path search algorithm, and the length of the shortest path is used as the distance value between the theoretical position and the actual position of the curvature data.

[0066] On the third aspect, when the user issues an active update instruction, the preloading strategy is determined to be the third loading strategy; the third loading strategy includes: determining the abnormality corresponding to the vehicle's driving speed, and determining the user's instruction intention based on the abnormality; setting the data importance of some sub-data in the detailed map data in each area in the subsequent loading queue based on the user's instruction intention; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map, and setting the corresponding distance threshold according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold.

[0067] It is understandable that when a user issues an active update instruction, such as when a user actively drags or updates the vehicle electronic map, it means that the user has a purposeful update demand at this time. In this case, the user may want to check the road conditions ahead or check the information around a target location. Therefore, it is necessary to obtain the user's possible update demand based on the real-time data obtained by the vehicle sensor at this time, and then provide a targeted loading strategy for it.

[0068] In a specific implementation, determining the abnormality corresponding to the driving speed of the vehicle specifically includes: The first step is to obtain the average speed of the vehicle during normal driving.

[0069] The second step is to subtract the driving speed from the mean speed to obtain the speed difference.

[0070] The third step is to divide the speed mean by 2 to get the speed comparison value.

[0071] The fourth step is to subtract the speed difference from the speed comparison value to obtain the intermediate speed value.

[0072] The fifth step is to input the intermediate value of the speed into the sign function to obtain the abnormality corresponding to the vehicle's driving speed.

[0073] In this embodiment, the mathematical expression of the abnormality corresponding to the vehicle's running speed is: (4) In the formula, Indicates the abnormality corresponding to the vehicle's driving speed. represents the sign function, Indicates the real-time speed of the vehicle. It represents the average speed of the vehicle during normal driving. Indicates the middle speed value.

[0074] In practical applications, the abnormality corresponding to the vehicle's driving speed has three values, namely -1, 0 and 1. When the middle value of the speed is a negative number, the abnormality corresponding to the vehicle's driving speed is -1. When the middle value of the speed is zero, the abnormality corresponding to the vehicle's driving speed is 0. When the middle value of the speed is a positive number, the abnormality corresponding to the vehicle's driving speed is 1.

[0075] When the abnormality value corresponding to the vehicle's driving speed is -1, it indicates that the vehicle's driving speed is abnormal.

[0076] Furthermore, when the abnormality value corresponding to the vehicle's driving speed is -1, the user's command intention is likely to check the road conditions ahead. When the abnormality value corresponding to the vehicle's driving speed is 0 or 1, the user's command intention is likely to check the information around a target location.

[0077] When the user's instruction is intended to check the road conditions ahead, the data importance of the sub-data containing road condition information in the detailed map data of the remaining area to be loaded is set to the highest, and then the loading order of each sub-data is determined from high to low according to the data importance; the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map is calculated, and the corresponding distance thresholds are set according to the loading order of each sub-data, and the sub-data with a distance value greater than the corresponding distance threshold is loaded.

[0078] When the user's instruction is intended to view information around a target location, the data importance of the sub-data containing the information around the target location in the detailed map data of the remaining area to be loaded is set to the highest, and then the loading order of each sub-data is determined from high to low according to the data importance; the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map is calculated, and the corresponding distance thresholds are set according to the loading order of each sub-data, and the sub-data with a distance value greater than the corresponding distance threshold is loaded.

[0079] In practical applications, since the sub-data that are loaded earlier in the order are relatively more important, the distance threshold should be set to be smaller. Therefore, the specific values ​​of each distance threshold can be set from small to large according to the loading order.

[0080] After determining the preloading order and preloading strategy, you can use the multi-core processor of the vehicle-mounted device to create the corresponding high-precision data rendering process. For example, create a road rendering thread, a terrain rendering thread, etc. The road rendering thread is responsible for drawing the road network in the vehicle electronic map, and drawing the line style and color of different levels of roads according to the road data in the preloaded area. At the same time, the terrain rendering thread can generate a three-dimensional model of the terrain and render it according to the terrain data in the area to be loaded.

[0081] In practical applications, an efficient file system, such as FAT32, can be used to store map data for the on-board electronic map rendering process, vehicle driving data, and various programs and configuration files required for system operation, and save them in a local database to facilitate data calls in the rendering process.

[0082] The rendering method for vehicle-mounted electronic maps proposed in the embodiment of the present invention determines the access weight values ​​of different areas in the vehicle-mounted electronic map through key data such as the driving speed and latitude and longitude coordinates of the vehicle during driving, and then determines the preloading order and preloading strategy of different areas in the vehicle-mounted electronic map based on the access weight value combined with the user's instruction intention when the user issues an active update instruction, thereby achieving accurate rendering of at least part of the area in the vehicle-mounted electronic map. Compared with the traditional rendering scheme, the preloading strategy of different areas in the vehicle-mounted electronic map can be dynamically adjusted according to the real-time behavior of the vehicle and user needs, and then the data of key areas in the vehicle-mounted electronic map can be fully loaded according to user needs, thereby improving the rendering effect of the vehicle-mounted electronic map.

[0083] Based on the same general inventive concept, the present invention also protects a rendering system suitable for a vehicle-mounted electronic map. The rendering system suitable for a vehicle-mounted electronic map provided by the present invention is described below. The rendering system suitable for a vehicle-mounted electronic map described below and the rendering method suitable for a vehicle-mounted electronic map described above can be referenced to each other.

[0084] like Figure 2 As shown, the rendering system for a vehicle-mounted electronic map provided by an embodiment of the present invention specifically includes: The acquisition module 210 is used to acquire the driving speed and longitude and latitude coordinates of the vehicle during driving.

[0085] The first processing module 220 is used to determine the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed.

[0086] The second processing module 230 is used to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate in each complete operation path according to the first access criticality in all complete driving cycles in each complete operation path.

[0087] The third processing module 240 is used to determine the third access criticality of each area in the vehicle-mounted electronic map according to all the second access criticalities corresponding to the same area.

[0088] The fourth processing module 250 is used to determine the preloading order and preloading strategy of each area according to the third access criticality of each area.

[0089] The rendering module 260 is used to render at least a part of the area in the vehicle-mounted electronic map according to the preloading sequence and the preloading strategy.

[0090] Regarding the system in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated again here.

[0091] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the rendering method for a vehicle-mounted electronic map provided in the above-mentioned embodiments is implemented. The method includes: obtaining the driving speed and longitude and latitude coordinates of the vehicle during driving; determining, based on the driving speed, a first access criticality of an area corresponding to each longitude and latitude coordinate in each complete driving cycle; calculating, based on the first access criticality in all complete driving cycles under each complete operating path, a second access criticality of an area corresponding to each longitude and latitude coordinate under each complete operating path; determining, based on all second access criticalities corresponding to the same area, a third access criticality of each area in the vehicle-mounted electronic map; determining, based on the third access criticality of each area, a preloading order and a preloading strategy for each area; and rendering at least part of the area in the vehicle-mounted electronic map according to the preloading order and the preloading strategy.

[0092] The device embodiments described above are merely illustrative, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0093] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0094] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0095] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A rendering method suitable for vehicle-mounted electronic maps, characterized in that: The method comprises: Obtain the vehicle's driving speed and longitude and latitude coordinates during driving; Determining the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed; According to the first access criticality in all complete driving cycles under each complete operation path, the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path is calculated; Determine the third access criticality of each area in the vehicle-mounted electronic map according to all the second access criticalities corresponding to the same area; Determine the preloading order and preloading strategy of each area according to the third access criticality of each area; According to the preloading sequence and the preloading strategy, at least a part of the area in the vehicle-mounted electronic map is rendered.

2. The rendering method for vehicle-mounted electronic maps according to claim 1, characterized in that: Determining the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle according to the driving speed includes: Determine the occurrence frequency value of each latitude and longitude coordinate of the vehicle in each complete driving cycle; According to the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated.

3. The rendering method for vehicle-mounted electronic maps according to claim 2, characterized in that: According to the occurrence frequency value of each longitude and latitude coordinate and the driving speed of the vehicle at the time of collecting each longitude and latitude coordinate, the first access criticality of the area corresponding to each longitude and latitude coordinate in each complete driving cycle is calculated, including: The frequency of occurrence of each longitude and latitude coordinate is divided by the sum of the vehicle's speed at the time of collection of each longitude and latitude coordinate and a preset non-zero constant value to obtain a user attention ratio; The user attention ratio is normalized to obtain the first access criticality of each area corresponding to each longitude and latitude coordinate in each complete driving cycle.

4. The rendering method for vehicle-mounted electronic maps according to claim 1, characterized in that: According to the first access criticality in all complete driving cycles under each complete operation path, the second access criticality of each latitude and longitude coordinate area corresponding to each complete operation path is calculated, including: The first access criticality in all complete driving cycles under each complete operation path is averaged to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path.

5. The rendering method for vehicle-mounted electronic maps according to claim 1, characterized in that: According to the third access criticality of each area, the preloading order and preloading strategy of each area are determined, including: Calculate the access weight value of each area according to the third access criticality of each area; According to the access weight value, determine the preloading order and data loading queue corresponding to each area in the vehicle electronic map; A preloading strategy for each area is determined according to the data loading queue.

6. The rendering method for vehicle-mounted electronic maps according to claim 5, characterized in that: The data loading queue includes a priority loading queue and a subsequent loading queue; According to the access weight value, determining the preloading order and data loading queue corresponding to each area in the vehicle electronic map includes: Determine the preloading order corresponding to each area in the vehicle-mounted electronic map according to the order of the access weight values ​​from large to small; Compare the access weight value of each area with the preset weight threshold to obtain a comparison result; The data corresponding to the area whose access weight value is higher than the preset weight threshold according to the comparison result is divided into a priority loading queue; The data corresponding to the area whose comparison result is that the access weight value is less than or equal to the preset weight threshold is divided into a subsequent loading queue.

7. The rendering method for vehicle-mounted electronic maps according to claim 6, characterized in that: According to the data loading queue, a preloading strategy for each area is determined, including: When the user does not issue an active update instruction and the vehicle does not travel to any area in the subsequent loading queue, the preloading strategy is determined to be the first loading strategy; the first loading strategy includes: loading detailed map data in the area in the priority loading queue, and loading basic map contour data in the area in the subsequent loading queue; When the user does not issue an active update instruction and the vehicle travels to any area in the subsequent loading queue, the preloading strategy is determined to be the second loading strategy; the second loading strategy includes: determining the data importance of each sub-data in the detailed map data in each area in the subsequent loading queue; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the vehicle-mounted electronic map, and setting the corresponding distance thresholds according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold; When the user issues an active update instruction, the preloading strategy is determined to be the third loading strategy; the third loading strategy includes: determining the abnormality corresponding to the vehicle's driving speed, and determining the user's instruction intention based on the abnormality; setting the data importance of some sub-data in the detailed map data in each area in the subsequent loading queue based on the user's instruction intention; determining the loading order of each sub-data from high to low according to the data importance; calculating the distance value between the theoretical position and the actual position of each sub-data in each area in the subsequent loading queue within the update range of the on-board electronic map, and setting the corresponding distance thresholds according to the loading order of each sub-data, and loading the sub-data with a distance value greater than the corresponding distance threshold.

8. The rendering method for vehicle-mounted electronic maps according to claim 7, characterized in that: Determine the abnormality corresponding to the vehicle's driving speed, including: Get the average speed of the vehicle when it is running normally; Subtract the driving speed from the speed average to obtain a speed difference; Divide the speed mean by 2 to obtain a speed comparison value; Subtract the speed difference from the speed comparison value to obtain a speed intermediate value; The intermediate speed value is input into the sign function to obtain the abnormality corresponding to the vehicle's running speed.

9. A rendering system suitable for vehicle-mounted electronic maps, characterized in that: The system comprises: An acquisition module is used to acquire the driving speed and longitude and latitude coordinates of the vehicle during driving; A first processing module, used for determining, according to the driving speed, a first access criticality of an area corresponding to each longitude and latitude coordinate in each complete driving cycle; The second processing module is used to calculate the second access criticality of each area corresponding to each longitude and latitude coordinate under each complete operation path according to the first access criticality in all complete driving cycles under each complete operation path; A third processing module, for determining the third access criticality of each area in the vehicle-mounted electronic map according to all second access criticalities corresponding to the same area; A fourth processing module, used for determining a preloading order and a preloading strategy for each area according to the third access criticality of each area; The rendering module is used to render at least a part of the area in the vehicle-mounted electronic map according to the preloading sequence and the preloading strategy.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the rendering method applicable to a vehicle-mounted electronic map as claimed in any one of claims 1 to 8 is implemented.

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