Perspective view angle display method for objects around vehicle

Abstract

The invention discloses a vehicle surrounding object perspective view angle display method, which comprises the following steps: acquiring a target object and a lane line under a vehicle coordinate system corresponding to a bird's-eye view angle, and determining a conversion range under the vehicle coordinate system, a display range of a screen coordinate system and a vehicle position point under two coordinate systems; the position of the target object in a screen coordinate system is obtained by combining the position, the conversion range and the display range of the target object relative to the vehicle in a vehicle coordinate system, the positions of the vehicle in different coordinate systems and a scaling set based on the perspective principle, then curve fitting is conducted on lane lines by combining the scaling and the coordinate conversion mode of the target object, and the target object is obtained. And obtaining the lane line under the screen coordinate system, so that visual display of a perspective angle can be realized on the display screen. The bird's-eye view angle information is converted into the perspective view angle, the trust degree of the driver on the intelligent driving system can be improved, the intelligent driving experience can be improved, and meanwhile, the visual information better fits the view angle of the driver with low resource consumption.

Description

Technical Field

[0001] The present invention relates to the field of intelligent driving assistance technology, and in particular to a method for displaying perspective viewing angles of objects surrounding a vehicle. Background Art

[0002] Intelligent driving assistance technology is booming, but its reliability has not yet been accepted by the general public, making it difficult for users to increase their confidence in intelligent driving assistance functions. Therefore, there is still much room for improvement in interaction and experience.

[0003] Specifically, with the improvement of computing power of instruments and car computers, most car companies have begun to visualize all the information around the vehicle (targets and lane lines, etc.) perceived by the intelligent driving system, as well as the route the vehicle is about to travel, on the instruments or car computers. However, the presentation is mostly through a bird's-eye view on the display carrier.

[0004] Although this solution can display basic information, it is only a two-dimensional display, which does not conform to the driver's real perspective. Not only is the experience poor, but the images presented are also difficult to gain the driver's trust. Even though there are a few solutions that try to establish a virtual three-dimensional space to model and display various targets and lane lines in three dimensions, the computing resources required to obtain a real visual experience are huge and cannot be popularized in actual applications. Summary of the invention

[0005] In view of the above, the present invention aims to provide a method for displaying objects around a vehicle in a perspective view to solve the above-mentioned technical problems.

[0006] The technical solution adopted by the present invention is as follows:

[0007] The present invention provides a method for displaying a perspective view of objects around a vehicle, comprising:

[0008] Acquire information about objects around the vehicle in a vehicle coordinate system corresponding to a bird's-eye view, wherein the objects around the vehicle include: target objects represented by points and lane lines represented by lines;

[0009] Determine the conversion range in the vehicle coordinate system and the display range in the screen coordinate system;

[0010] Determine the correspondence between the vehicle position point in the vehicle coordinate system and the vehicle position point in the screen coordinate system;

[0011] The zoom ratio is determined by combining the conversion range, the display range, the corresponding relationship and the perspective principle that things are larger when they are near and smaller when they are far away, and the position of the target object in the screen coordinate system is obtained by combining the position of the target object relative to the vehicle in the vehicle coordinate system;

[0012] After executing the coordinate conversion process based on the scaling ratio, curve fitting is performed to obtain the lane line in the screen coordinate system;

[0013] The position of the target object in the screen coordinate system and the fitting curve representing the lane line are used to give a perspective visual display on the display screen.

[0014] In at least one of the possible implementations:

[0015] The conversion range is represented by the coordinates of the four corner points of the rectangle;

[0016] The display range is represented by the coordinates of the four corner points of a trapezoid that is shorter at the top and longer at the bottom;

[0017] And the vehicle is located in the middle position below the conversion range and the display range.

[0018] In at least one possible implementation manner, obtaining the position of the target object in the screen coordinate system includes:

[0019] Calculate the longitudinal distance between the target object and the vehicle in the screen coordinate system by using the maximum longitudinal distance in front of the vehicle in the conversion range, the maximum longitudinal distance in front of the vehicle in the display range, and the longitudinal distance between the target object and the vehicle in the vehicle coordinate system;

[0020] The lateral distance between the target object and the vehicle in the screen coordinate system is calculated by using the maximum lateral distance on one side of the vehicle within the conversion range, the two lateral distances on one side of the vehicle within the display range, the maximum longitudinal distance in front of the vehicle within the display range, the longitudinal distance between the target object and the vehicle in the screen coordinate system, and the lateral distance between the target object and the vehicle in the vehicle coordinate system.

[0021] In at least one possible implementation, obtaining the lane line in the screen coordinate system includes:

[0022] Select at least three reference points on the lane line of the vehicle coordinate system;

[0023] Obtaining the position of the corresponding point of each reference point in the screen coordinate system in a manner of obtaining the position of the target object in the screen coordinate system;

[0024] A matrix calculation is performed based on the positions of the corresponding points and fitted into a quadratic curve equation.

[0025] In at least one possible implementation, the vehicle coordinate system is constructed with the center of the rear axle of the vehicle as the coordinate origin, the forward direction of the vehicle as the X-axis, and one side of the vehicle as the Y-axis.

[0026] In at least one possible implementation, the upper left corner of the display screen of the instrument or vehicle computer is used as the coordinate origin, and the screen coordinate system is constructed with its right side as the X-axis and its bottom as the Y-axis.

[0027] Compared with the prior art, the main design concept of the present invention is to obtain the target object and lane line in the vehicle coordinate system corresponding to the bird's-eye view, determine the conversion range in the vehicle coordinate system, the display range in the screen coordinate system, and the correspondence between the vehicle position point in the vehicle coordinate system and the vehicle position point in the screen coordinate system; combine the position of the target object relative to the vehicle in the vehicle coordinate system, the conversion range, the display range, the position of the vehicle in different coordinate systems, and the scaling ratio set based on the perspective principle to obtain the position of the target object in the screen coordinate system, and then combine the scaling ratio and the coordinate conversion method of the target object to curve fit the lane line to obtain the lane line in the screen coordinate system, so that the lane line can be visualized on the display screen with a perspective perspective. The present invention transforms the bird's-eye view information into a perspective perspective, which can enhance the driver's trust in the intelligent driving system and improve the intelligent driving experience, while making the visual information more in line with the driver's perspective with lower resource consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described below with reference to the accompanying drawings, in which:

[0029] Figure 1 A schematic diagram of a method for displaying a perspective view of objects around a vehicle provided by an embodiment of the present invention;

[0030] Figure 2 A flow chart of the conversion relationship between two coordinate systems of a target point provided by an embodiment of the present invention;

[0031] Figure 3 A schematic diagram of a vehicle coordinate system and a conversion range provided by an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of a screen coordinate system and a display range provided in an embodiment of the present invention;

[0033] Figure 5 A flow chart of the conversion relationship between two coordinate systems of lane lines provided in an embodiment of the present invention;

[0034] Figure 6 A schematic diagram of the conversion of lane lines between two coordinate systems provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0036] The present invention proposes an embodiment of a method for displaying a perspective view of objects around a vehicle. Specifically, Figure 1 shown, including:

[0037] Step S1, obtaining objects around the vehicle in a vehicle coordinate system corresponding to a bird's-eye view, wherein the objects around the vehicle include: target objects represented by points and lane lines represented by lines;

[0038] In actual operation, the visual and radar perception units on the vehicle can output the surrounding objects of the vehicle in the vehicle coordinate system after processing by the perception data fusion module, such as target objects (such as cars, people, trees, poles, signs, obstacles, etc.) and lane lines. Specifically, the position of the target object can be reflected by the coordinate points, and the lane lines can be reflected by the curve equation parameters. Of course, in addition to points and lines, the surface elements around the vehicle can be further expanded, such as buildings, venues, etc.

[0039] It should be pointed out that the vehicle coordinate system described in this section is mainly constructed with the center of the vehicle's rear axle as the coordinate origin, the vehicle's forward direction as the X-axis, and one side of the vehicle (the left side for a left-hand drive vehicle) as the Y-axis.

[0040] Step S2, determining the conversion range in the vehicle coordinate system and the display range in the screen coordinate system;

[0041] The first thing that can be pointed out here is that the screen coordinate system takes the upper left corner of the instrument or car display screen as the coordinate origin, and is constructed with the right side as the X-axis and the bottom as the Y-axis.

[0042] like Figure 2 As shown in the figure, it is the conversion relationship process between the target point in the two coordinates: first determine the conversion range in the vehicle coordinate system (bird's eye view) (such as Figure 3 The conversion range is usually a rectangle, which allows you to use the coordinates of the four corner points of the rectangle to clearly define the range limit.

[0043] Next, the displayable range of the instrument or vehicle display screen is determined. The present invention believes that conversion to a perspective perspective will visually reflect a more three-dimensional sense. Specifically, the displayable range of the instrument or vehicle display screen can be a trapezoid with a small top and a large bottom (such as Figure 4 The area enclosed by the frame line shown), the coordinates of the four corner points of the trapezoid can also be used to conveniently indicate the display range.

[0044] Step S3, determining the correspondence between the vehicle position point in the vehicle coordinate system and the vehicle position point in the screen coordinate system;

[0045] Based on the fact that the vehicle is located in the center and below the display in any coordinate system ( Figure 3 and Figure 4 The solid block in , which represents the ego vehicle), can thus determine the correspondence between the ego vehicle position point in the vehicle coordinate system and the ego vehicle position point in the screen coordinate system.

[0046] Step S4, determining a zoom ratio by combining the conversion range, the display range, the corresponding relationship, and the perspective principle that objects are larger near and smaller far away, and obtaining a position of the object in the screen coordinate system according to the position of the object relative to the vehicle in the vehicle coordinate system and the zoom ratio;

[0047] Specifically, the relative relationship between a target point (i.e., an embodiment of the object around the vehicle, a target vehicle is used as an example in the figure) and the vehicle is determined in the vehicle coordinate system: the target point coordinates (y, x); to the screen coordinate system (the instrument coordinate system is used as an example in the figure), the relative position coordinates (X, Y) of this target point and the vehicle, thereby realizing the target coordinate conversion. The following is a specific coordinate conversion method:

[0048] Assume that in the vehicle coordinate system, the maximum longitudinal distance of the conversion range in front of the vehicle is d, and the maximum lateral distance is w; assume that in the screen coordinate system, the longitudinal range of the display range is D, the upper end of the lateral range is W1, and the lower end of the lateral range is W2.

[0049] Assuming that in the vehicle coordinate system, the longitudinal distance between the target point and the vehicle is x, and the lateral distance is y, then according to the perspective effect of near is large and far is small, and the longitudinal distance change of the target point closer to the vehicle is more obvious, and the longitudinal distance change of the target point closer to the vehicle is less obvious, the longitudinal value of the target point and the vehicle (that is, the Y-axis coordinate in the screen coordinate system) can be calculated in the screen coordinate system. The formula is as follows:

[0050] Then, based on the principle of similar triangles, the lateral value of the target point and the vehicle (i.e. the X-axis coordinate in the screen coordinate system) can be calculated in the screen coordinate system. The formula is as follows:

[0051] Step S5, performing coordinate conversion processing based on the scaling ratio and then performing curve fitting to obtain lane lines in the screen coordinate system;

[0052] Step S6: Use the target object and lane line in the screen coordinate system to provide a perspective visual display on the display screen (of course, in some non-limiting embodiments, the orientation of the target vehicle can also be determined based on the position of the target vehicle in the screen coordinate system and its associated lane line parameters, that is, the lane line curve and the target vehicle can be used to further draw the posture of the target vehicle).

[0053] For the coordinate transformation of the lane line, it can be Figure 5 The specific steps are shown below:

[0054] It is known that in the vehicle coordinate system, the lane line is preferably fitted using a cubic polynomial as follows:

[0055] Assume that in the screen coordinate system, the lane line is a quadratic equation and the parameters of the curve equation are:

[0056] Therefore, the curve can be expressed as:

[0057] In actual operation, first, in the vehicle coordinate system, three special points (x1, y1), (x2, y2) and (x3, y3) can be selected, that is, at least three reference points are used as the reference points of the lane line (the lane line is not absolutely straight, so it is recommended to have at least three reference points). The three special points are transformed into three corresponding points (X1, Y1), (X2, Y2) and (X3, Y3) in the screen coordinate system, and finally the following matrix is ​​used to calculate and fit the quadratic curve equation, such as Figure 6 As shown in the schematic diagram, assume:

[0058] The parameters of the quadratic equation are calculated as follows:

[0059]

[0060] Based on the above steps, the coordinate transformation of a lane line is completed. By repeating this operation, the perspective presentation of multiple lane lines perceived around the vehicle on the display screen can be completed.

[0061] In summary, the main design concept of the present invention is to obtain the target object and lane line in the vehicle coordinate system corresponding to the bird's-eye view, determine the conversion range in the vehicle coordinate system, the display range in the screen coordinate system, and the correspondence between the vehicle position point in the vehicle coordinate system and the vehicle position point in the screen coordinate system; combine the position of the target object relative to the vehicle in the vehicle coordinate system, the conversion range, the display range, the position of the vehicle in different coordinate systems, and the scaling ratio set based on the perspective principle to obtain the position of the target object in the screen coordinate system, and then combine the scaling ratio and the coordinate conversion method of the target object to curve fit the lane line to obtain the lane line in the screen coordinate system, so that it can be visualized on the display screen with a perspective perspective. The present invention transforms the bird's-eye view information into a perspective perspective, which can enhance the driver's trust in the intelligent driving system and improve the intelligent driving experience, while making the visual information more in line with the driver's perspective with lower resource consumption.

[0062] If the expressions expressing orientation are mentioned in the embodiments of the present invention, they are relative concepts based on the embodiments. In addition, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b, c can be single or multiple.

[0063] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings, but the above is only a preferred embodiment of the present invention. It should be noted that the technical features involved in the above embodiments and their preferred methods can be reasonably combined and matched into a variety of equivalent schemes by those skilled in the art without departing from or changing the design ideas and technical effects of the present invention; therefore, the present invention is not limited to the scope of implementation shown in the drawings, and all changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification and drawings, should be within the protection scope of the present invention.

Claims

1. A method for displaying a perspective view of objects around a vehicle, characterized in that: include: Acquire information about objects around the vehicle in a vehicle coordinate system corresponding to a bird's-eye view, wherein the objects around the vehicle include: target objects represented by points and lane lines represented by lines; Determine the conversion range in the vehicle coordinate system and the display range in the screen coordinate system; Determine the correspondence between the vehicle position point in the vehicle coordinate system and the vehicle position point in the screen coordinate system; The zoom ratio is determined by combining the conversion range, the display range, the corresponding relationship and the perspective principle that things are larger when they are near and smaller when they are far away, and the position of the target object in the screen coordinate system is obtained by combining the position of the target object relative to the vehicle in the vehicle coordinate system; After executing the coordinate conversion process based on the scaling ratio, curve fitting is performed to obtain the lane line in the screen coordinate system; The position of the target object in the screen coordinate system and the fitting curve representing the lane line are used to give a perspective visual display on the display screen.

2. The method for displaying vehicle surrounding objects in perspective according to claim 1, characterized in that: The conversion range is represented by the coordinates of the four corner points of the rectangle; The display range is represented by the coordinates of the four corner points of a trapezoid that is shorter at the top and longer at the bottom; And the vehicle is located in the middle position below the conversion range and the display range.

3. The method for displaying the perspective view of objects around a vehicle according to claim 2, characterized in that: The obtaining of the position of the target object in the screen coordinate system includes: Calculate the longitudinal distance between the target object and the vehicle in the screen coordinate system by using the maximum longitudinal distance in front of the vehicle in the conversion range, the maximum longitudinal distance in front of the vehicle in the display range, and the longitudinal distance between the target object and the vehicle in the vehicle coordinate system; The lateral distance between the target object and the vehicle in the screen coordinate system is calculated by using the maximum lateral distance on one side of the vehicle within the conversion range, the two lateral distances on one side of the vehicle within the display range, the maximum longitudinal distance in front of the vehicle within the display range, the longitudinal distance between the target object and the vehicle in the screen coordinate system, and the lateral distance between the target object and the vehicle in the vehicle coordinate system.

4. The method for displaying the perspective view of objects around a vehicle according to claim 3, characterized in that: The obtaining of the lane line in the screen coordinate system includes: Select at least three reference points on the lane line of the vehicle coordinate system; Obtaining the position of the corresponding point of each reference point in the screen coordinate system in a manner of obtaining the position of the target object in the screen coordinate system; A matrix calculation is performed based on the positions of the corresponding points and fitted into a quadratic curve equation.

5. The method for displaying vehicle surrounding objects in perspective according to any one of claims 1 to 4, characterized in that: The vehicle coordinate system is constructed with the center of the rear axle of the vehicle as the coordinate origin, the forward direction of the vehicle as the X-axis, and one side of the vehicle as the Y-axis.

6. The method for displaying vehicle surrounding objects in perspective according to any one of claims 1 to 4, characterized in that: The screen coordinate system is constructed with the upper left corner of the display screen of the instrument or vehicle computer as the coordinate origin, and the right side thereof as the X-axis and the bottom as the Y-axis.

Images