Point cloud encryption method and device, storage medium and lidar

Abstract

This application discloses a point cloud encryption method, apparatus, storage medium, and lidar, applied to lidar. The lidar includes a transmitter group and a scanning device. The method includes: obtaining the point cloud encryption factor for each level of detection field of view; obtaining the scan line interval corresponding to two adjacent transmissions based on the point cloud encryption factor for each level of detection field of view; and scanning according to the scan line interval corresponding to two adjacent transmissions. The lidar includes a first scanning direction and a second scanning direction, and the inter-group interval of the scan lines corresponding to two adjacent transmissions is achieved by scanning in the first scanning direction. Using this application, while satisfying human eye safety, ROI encryption can be achieved by controlling the scan line interval corresponding to two adjacent transmission groups, thus improving the detection efficiency of lidar.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a point cloud encryption method, device, storage medium, and lidar. Background Technology

[0002] LiDAR (Light Detection and Ranging) can directly and rapidly image three-dimensional space with high precision, thus becoming one of the main sensors in current autonomous driving technology. Currently, the development of LiDAR mainly focuses on achieving stronger ranging capabilities, higher point cloud density, and compliance with human eye safety regulations. Automotive LiDAR operates in the infrared wavelength band, primarily around 900nm and 1500nm. 1500nm LiDAR has a higher human eye safety threshold, but the transmitting and receiving modules for this type of LiDAR are very expensive due to material limitations, making large-scale commercialization difficult in the short to medium term. For 900nm LiDAR, the human eye safety threshold is lower, limiting the continuous improvement of its point cloud density while meeting specific ranging performance requirements.

[0003] Improving ranging performance and increasing the density of the detected point cloud while ensuring human eye safety has become an urgent problem to be solved. Summary of the Invention

[0004] This application provides a point cloud encryption method, device, storage medium, and lidar. While ensuring eye safety, it achieves ROI encryption by controlling the scan line interval between two adjacent transmissions, thereby improving lidar detection efficiency. The technical solution is as follows:

[0005] In a first aspect, embodiments of this application provide a point cloud encryption method applied to a lidar system, the lidar system including a transmitter group and a scanning device, the method comprising:

[0006] Obtain the point cloud encryption factor for each level of the detection field of view;

[0007] Based on the point cloud encryption factor of each level of detection field of view, the scan line interval corresponding to two adjacent transmissions is obtained;

[0008] Scanning is performed according to the scan line interval corresponding to two adjacent transmissions.

[0009] Secondly, embodiments of this application provide a point cloud density encryption device applied to a lidar, the lidar including a transmitter group and a scanning device, the device comprising:

[0010] The encryption multiplier acquisition module is used to acquire the point cloud encryption multiplier for each level of the detection field of view;

[0011] The interval calculation module is used to obtain the scan line interval between two adjacent transmissions based on the point cloud encryption multiple of each level of detection field of view.

[0012] The scanning module is used to scan according to the scan line interval corresponding to the two adjacent transmissions.

[0013] Thirdly, embodiments of this application provide a computer storage medium storing a plurality of instructions adapted for loading by a processor and executing the above-described method steps.

[0014] Fourthly, embodiments of this application provide a lidar, which may include: a processor and a memory; wherein the memory stores a computer program adapted to be loaded by the processor and executed by the above-described method steps.

[0015] The beneficial effects of the technical solutions provided in some embodiments of this application include at least the following:

[0016] By adopting the embodiments of this application, the point cloud encryption factor of each level of detection field of view is obtained, and the scan line interval corresponding to two adjacent transmissions is obtained based on the point cloud encryption factor. Scanning is performed according to the scan line interval of two adjacent transmissions. While satisfying human eye safety, the encryption of ROI can be achieved by controlling the scan line interval of two adjacent sets of transmissions, thereby improving the efficiency of lidar detection. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an example schematic diagram of point cloud density distribution in the horizontal and vertical directions provided in an embodiment of this application;

[0019] Figure 2 This is a flowchart illustrating a point cloud encryption method provided in an embodiment of this application;

[0020] Figure 3 This is an example schematic diagram of obtaining the scan line interval corresponding to two adjacent transmissions provided in an embodiment of this application;

[0021] Figure 4a This is a schematic diagram of the transmitter arrangement in the same transmitting group provided in an embodiment of this application;

[0022] Figure 4b This is a schematic diagram of another transmitter arrangement in the same group of transmitters provided in an embodiment of this application;

[0023] Figure 4c This is a schematic diagram of another transmitter arrangement in the same group of transmitters provided in an embodiment of this application;

[0024] Figure 5 This is an example schematic diagram of point cloud distribution in the horizontal and vertical directions provided in an embodiment of this application;

[0025] Figure 6 This is an example schematic diagram illustrating how to increase point cloud density in the horizontal direction, as provided in an embodiment of this application.

[0026] Figure 7 This is another example of increasing point cloud density in the horizontal direction provided by an embodiment of this application;

[0027] Figure 8 This is an example schematic diagram of a point cloud distribution in the vertical direction provided in an embodiment of this application;

[0028] Figure 9 This is an example schematic diagram illustrating how to increase point cloud density in the vertical direction, as provided in an embodiment of this application.

[0029] Figure 10 This is an example diagram illustrating another way to increase point cloud density in the vertical direction, provided in an embodiment of this application.

[0030] Figure 11 This is an example schematic diagram illustrating how to improve point cloud density in a one-shot-multiple-connection mode, as provided in an embodiment of this application.

[0031] Figure 12 This is an example diagram illustrating another way to improve point cloud density in a single-shot multi-connection mode, as provided in an embodiment of this application.

[0032] Figure 13 This is a schematic diagram of the structure of a point cloud encryption device provided in an embodiment of this application;

[0033] Figure 14 This is a schematic diagram of the structure of a lidar provided in an embodiment of this application. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0035] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0036] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0037] The present application will now be described in detail with reference to specific embodiments.

[0038] Vehicle-mounted LiDAR systems operate in the infrared band, primarily around 900nm and 1500nm. LiDAR in the 1500nm band has a higher eye safety threshold; however, the transmitting and receiving modules for this type of LiDAR are very expensive due to material limitations, making large-scale commercialization difficult in the short to medium term. On the other hand, 900nm LiDAR has a lower eye safety threshold, which limits the continuous improvement of its point cloud density while meeting specific ranging performance requirements.

[0039] In practical applications, only at long distances and within the detection field of view close to vehicles and roads do lidar require a high point cloud density. At other locations, a lower point cloud density is sufficient for detecting the surrounding environment. Therefore, the lidar industry has introduced the concept of Region of Interest (ROI). The ROI is generally the area of ​​interest to the lidar, and high point cloud density is typically required within it. It's understandable that lidar also includes a general detection area, which is the area outside the ROI in the total detection field of view. The ROI can also be called the target detection field of view, and the general detection area can be called the general detection field of view. The sum of the target detection field of view and the general detection field of view constitutes the total detection field of view of the lidar.

[0040] The detection field of view of a typical lidar can be divided into two dimensions: vertical and horizontal. In a typical lidar, the point cloud density is uniformly distributed throughout the entire detection field of view, such as... Figure 1 As shown in the top left corner, the ROI case includes the following: horizontal point cloud density enhancement, such as... Figure 1 As shown in the upper right corner; vertical point cloud density is increased, such as... Figure 1 As shown in the lower left corner; both horizontal and vertical point cloud densities are simultaneously increased, as shown below. Figure 1 As shown in the bottom right corner.

[0041] The following will be combined with the appendix Figure 2- Appendix Figure 11 This application provides a detailed description of the point cloud encryption method provided in its embodiments. This method can be implemented using a computer program and can run on a point cloud encryption device based on the von Neumann architecture. This computer program can be integrated into an application or run as a standalone utility application. The point cloud encryption device in this application embodiment may include, but is not limited to, a lidar, vehicle-mounted equipment, an aircraft, a train, a handheld device, a wearable device, a computing device, or other processing devices connected to a wireless modem. The lidar includes a transmitter group, a scanning device, a receiving device, and a signal processor.

[0042] Please see Figure 2 The above is a flowchart illustrating a point cloud encryption method provided in this application embodiment.

[0043] like Figure 2 As shown, the method described in this application embodiment may include the following steps:

[0044] S101, obtain the point cloud encryption factor for each level of detection field of view;

[0045] It is understood that the detection field of view of a lidar includes the total detection field of view and the target detection field of view. The target detection field of view is the region of interest (ROI). Depending on the required point cloud density of the target detection field of view, it may include at least one level of detection field of view, such as a first-level field of view, a second-level field of view, etc. It is understood that this application does not limit the number of target detection fields of view. For example, the target detection field of view may include a first-level field of view, a second-level field of view, a third-level field of view, ..., an n-level field of view, etc.

[0046] It is understood that, as an optional embodiment, the point cloud density of each level of the detection field of view can be related to the level of the detection field of view. For example, the lower the level, the higher the point cloud density, exhibiting a regular variation. For instance, the first-level detection field of view has the highest point cloud density, followed by the second-level, and so on, with the nth-level detection field of view having the lowest point cloud density, where n > 2. Optionally, the point cloud density of each level of the detection field of view can also be less strongly correlated with the level of the detection field of view, i.e., as long as the point cloud density of each level of the target detection field of view is different. For example, the first-level detection field of view has the highest point cloud density, followed by the nth-level, and so on, with the second-level detection field of view having the lowest point cloud density, where n > 2. Here, the point cloud density of each level of the target detection field of view is different. It is understood that, as an optional embodiment, the required point cloud density multiple for each level of the detection field of view can be completely different. In one optional embodiment, the primary detection field of view is the central detection field of view, and the secondary detection field of view is a secondary encrypted field of view between the central detection field of view and the general detection field of view. Each level of detection field of view corresponds to a certain encryption factor. This encryption factor can be set according to current needs.

[0047] S102, based on the point cloud encryption multiple of the detection field of view at each level, obtain the scan line interval corresponding to two adjacent transmissions;

[0048] A lidar can emit N scanning points at a time. It can be understood that when the lidar includes multiple emission groups, the N scanning points can be the emitted laser from one emission group, or the N scanning points formed by multiple emission groups emitting simultaneously.

[0049] As an optional embodiment of this application, when the lidar includes two scanning directions, the interval between the scan lines can be achieved by scanning with a scanning device in one dimension. For example, the lidar can emit N scan points at a time, forming N scan lines, with a scan line interval of δθ, and the rotational speeds in the two scanning directions (horizontal and vertical directions) are labeled ω. \\ and ω ⊥ It should be noted that the functions of these two directions are interchangeable. Within one scan cycle, the angle at which the light changes in the horizontal direction to complete one scan cycle is denoted as α. perood The horizontal detection field of view is labeled α. FOV At this time α FOV ≤α period .

[0050] In the vertical direction, the interval between groups of scan lines corresponding to two adjacent emission points is denoted as δβ. This interval can be achieved by scanning in one dimension using a scanning device. For example, in the vertical direction, the scanning device can move at a constant speed throughout the entire scanning cycle, such as... Figure 3 As shown, at this point, we can obtain:

[0051]

[0052] If the angle α of the light changes during the scanning cycle period Detection field of view α greater than the horizontal direction FOV The scanning device can then quickly rotate through an angle in a non-light-emitting area to achieve this, such as... Figure 3 As shown, at this time:

[0053]

[0054] By adjusting the scanning method of the scanning device in one dimension to set δβ, the form of the detected point cloud can be set more reasonably.

[0055] It is understood that the scanning device in one dimension can be, for example, a rotating mirror, a one-dimensional galvanometer, or a rotating platform; this application does not limit the scanning device in this dimension. Similarly, the scanning device in another dimension can also be, for example, a rotating mirror, a one-dimensional galvanometer, or a rotating platform; this application does not limit the type of scanning device in either dimension. It is understood that the types of the scanning device in the first dimension and the second dimension can be the same or different, and this application does not impose any restrictions. As a preferred embodiment, the scanning devices in the two dimensions can be controlled independently. It is understood that by reasonably selecting the scan line interval δθ and the inter-group interval δβ between adjacent groups of scan lines, various encryption modes can be combined. It should be noted that δβ can be implemented in ways not limited to those described above. It is understood that the scan line interval δθ can be implemented by setting the interval of the transmitter arrangement, or by controlling the emitted laser to emit at intervals. It should be noted that the scan line interval δθ can be implemented in ways not limited to those described above. It is understood that the same emission group can be arranged in one column or in different columns. It is understandable that when the same launch group is arranged in two columns, it can be done through methods such as... Figure 4a As shown, arranging all the transmitters in the same transmitting group in a staggered manner can reduce δθ; as Figure 4b As shown, optionally, transmitters can be arranged in a staggered pattern in certain areas to reduce the δθ of the target area, such as... Figure 4b As shown, the spacing between transmitters in the edge region is δθ1, and the spacing between transmitters in the center region is δθ2, where δθ2 ≤ δθ1. This design allows for further improvement of the point cloud density in the target region while maintaining a constant interval between two emission angles. It can be understood that when transmitters from the same emission group are arranged in a row, a denser point cloud in the target region can also be achieved by setting unequal spacing between the transmitters at the edges and in the center. Figure 4c As shown, the interval between edge emitters in the same emission group is δθ1, and the interval between center emitters is δθ2, where δθ2 ≥ δθ1. It can be understood that the angular interval of the emission devices in the emission groups of the edge and center fields of view, and the number of scanning groups, can be determined based on the point cloud density requirements of the target field of view and the edge field of view.

[0056] The emitter can be a vertical-cavity surface-emitting laser (VCSEL) or an edge-emitting laser (EEL). Optionally, it can also be a fiber laser, forming an output array through a specific beam splitting method. This application does not limit the type of emitter. It is understood that the multiple emission groups can be arranged in one column or in different columns, and this application does not limit the specific arrangement of the multiple emission groups. As an optional embodiment, the spacing between the lasers in different emission groups can be the same or different, and this application does not limit this.

[0057] Specifically, if the lidar operates in a one-to-one transmit / receive mode, meaning one transmitter corresponds to one receiver, and the point cloud density includes horizontal or vertical resolution, the scan line interval δθ of each transmission group is obtained; the product of the number of scan lines N in each detection field of view and the scan line interval δθ of each transmission group is calculated; the quotient of this product and the encryption factor n of the point cloud density is then calculated to obtain the scan line interval between two adjacent transmissions. The scan line interval between two adjacent transmissions refers to the interval between the first scan line of each transmission. It can be understood that when the two transmissions are from the same transmission group, the scan interval is the step size of the scanning device in the first direction. It can be understood that horizontal or vertical encryption can be achieved by setting the step size of the scanning device in the same direction.

[0058] Furthermore, when the transmission interval is fixed, vertical or horizontal encryption can be achieved by setting the encryption multiplier and the number of transmitters corresponding to the same transmission group.

[0059] It can be understood that when the interval between the scan lines of each transmission group is determined, and the encryption multiplier n is a prime number that cannot be divided evenly by the number N of transmitters in the same transmission group, the interval between the scan lines of two transmissions can achieve vertical encryption.

[0060] It can be understood that when the interval between the scan lines of each transmission group is determined, and the encryption multiplier n is an integer divisible by the number N of transmitters in the same transmission group, the interval between the scan lines of two transmissions can achieve horizontal encryption.

[0061] S103, scan according to the scan line interval corresponding to the two adjacent transmissions.

[0062] By scanning according to the scan line intervals corresponding to two adjacent transmissions as set above, point cloud encryption can be achieved in the horizontal and / or vertical directions.

[0063] It is understandable that when the interval between the two scan lines corresponding to the two transmissions can be achieved by scanning with a scanning device in one dimension, and the two adjacent transmissions are the scan line interval between two transmissions from the same transmission group, then the scanning interval is the step size of the scanning device in that dimension.

[0064] It is understood that the same emission group can be lasers arranged in a single column, a single row, two columns, or two rows. This application does not limit the arrangement of lasers in the same emission group.

[0065] The lidar includes a first scanning direction and a second scanning direction. The interval of the scanning lines is achieved by scanning with a scanning device in the first scanning direction. If the angle of change of the light in one scanning cycle in the second direction is greater than the detection field of view set in the second direction, the difference between the angle of change of the light in one scanning cycle in the second direction and the detection field of view set in the second direction is calculated. The quotient of the difference and the scanning speed in the second direction is calculated to obtain the time corresponding to the two adjacent transmissions corresponding to the scanning line interval. The transmission group emits detection lasers to the scanning device according to the time, and the scanning device emits the detection lasers to the detection field of view for scanning.

[0066] When the scanning device moves at a constant speed in the second direction, the scanning speed in the second direction is the constant speed of the scanning device; when the scanning device moves at a non-constant speed in the second direction, the scanning speed in the second direction is the average speed of the scanning device in the second direction.

[0067] By adopting the embodiments of this application, the encryption factor of the point cloud of each level of detection field of view is obtained. Based on the encryption factor of the point cloud of each level of detection field of view, the scan line interval corresponding to two adjacent transmissions is obtained, and scanning is performed according to the scan line interval corresponding to two adjacent transmissions. While satisfying human eye safety, the encryption of the ROI area can be achieved by controlling the scan line interval corresponding to two adjacent transmissions, thereby improving the efficiency of lidar detection.

[0068] Please see Figure 5 This is a flowchart illustrating a point cloud encryption method provided in an embodiment of this application. Figure 5 As shown, the encryption method for this point cloud may include the following steps:

[0069] S201, Obtain the point cloud encryption factor for each level of detection field of view;

[0070] The number of scan lines emitted by the emitter group is based on the performance of the emitter group itself. For example, the number of scan lines in each emitter group is N, and the interval between each two scan lines is δθ.

[0071] Based on encryption requirements, each level of detection field of view is assigned a corresponding number of scan lines N. For example, the number of scan lines in the first-level detection field of view is N1, and the number of scan lines in the second-level detection field of view is N2.

[0072] Specifically, the point cloud encryption factor n = N / X of each level of detection field of view is obtained by calculating the quotient of the number of scan lines N of each level of detection field of view and the number of scan lines X of each group of transmission groups.

[0073] S202, the lidar is a one-to-one transmission mode, the point cloud encryption factor includes a horizontal point cloud encryption factor or a vertical point cloud encryption factor, the scan line interval of each transmission group is obtained; the product of the number of scan lines in each transmission group and the scan line interval of each transmission group is calculated, and the quotient of the product and the horizontal point cloud encryption factor or the vertical point cloud encryption factor is calculated to obtain the scan line interval corresponding to two adjacent transmissions;

[0074] Specifically, if the lidar operates in a one-transmit, one-receive mode, meaning one transmitter corresponds to one receiver, the point cloud encryption factor includes either a horizontal point cloud encryption factor or a vertical point cloud encryption factor. The scan line interval δθ for each transmitter group is obtained; the product of the number of scan lines N in each transmitter group and the scan line interval δθ is calculated; the quotient of this product and the encryption factor n of the horizontal point cloud density is then calculated to obtain the scan line interval corresponding to two adjacent transmissions.

[0075] Figure 6 The image illustrates a horizontal encryption method. It assumes that a density of [density value] needs to be achieved in the central detection field of view. For the scan lines, it is necessary to make:

[0076]

[0077] In the formula, n is a number that is divisible by N. For example... Figure 6 As shown, N is 6 and n is 2. It can be seen that the scan lines for the center detection field of view are scanned twice. Assume the horizontal scan line interval is δθ. \\ During the first scan, the scan time was set to 0, δθ \\ ,2δθ \\ …During the second scan, the scan time was selected as… Two scans can be combined to obtain a horizontal resolution of The distribution of scan points increases the point cloud density in the horizontal direction. It should be noted that by controlling the timing of this transmission, repeating the scan several times in the horizontal direction can increase the point cloud density by several times. In other words, by keeping the vertical position of the two scans constant and changing the scan time interval, the horizontal encryption factor can be changed.

[0078] When n=2, encryption only occurs in the middle group, thus doubling the horizontal resolution of the ROI region. When n>2, the resolution of the central region is n times its original value. As the ROI region extends from the center towards the edges, the resolution gradually increases to n-1 times, n-2 times, n-3 times, and finally returns to the original resolution. This is for illustrative purposes only. Figure 7 The scan line characteristics are shown for cases where n=2 and n=3.

[0079] Figure 8 The diagram illustrates the vertical encryption method. For N scan lines with an interval of δθ, when δβ is Nδθ, the two sets of scan lines in the vertical direction are exactly offset. The arrows represent the changes in the vertical angle during different scans.

[0080] S203, the lidar is a one-to-one transmission mode, the point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor, obtain the scan line interval of each transmission group; calculate the first product of the number of scan lines in each transmission group and the scan line interval of each transmission group; calculate the second product of the horizontal point cloud encryption factor and the vertical point cloud encryption factor; calculate the quotient of the first product and the second product to obtain the scan line interval corresponding to two adjacent transmissions.

[0081] Based on the aforementioned horizontal density enhancement, interpolation methods can also be used, thus enabling simultaneous enhancement of both vertical and horizontal density in the central detection field of view.

[0082] First, let's briefly explain interpolation. For example... Figure 9 As shown in the figure, the laser emits a set of scan lines at different times, labeled A, B, C, and D. Assume that the number of scan lines in each group is N (i.e., the number of emitters in each group), and the scan line interval is δθ. As time changes, the scan lines scan downwards, gradually moving from A to B, C, and D (indicated by arrows), moving downwards by N lines each time.

[0083] Based on the interpolation method, the scanning interval can be set as:

[0084]

[0085] Where ′ represents the number of vertical encryption attempts, n represents the number of horizontal encryption attempts, N represents the number of transmitters, and n is a number divisible by N. At this point, in the central region, in addition to the inserted scan lines, each group of scan lines will be scanned an additional n times. This can be understood as follows: when performing horizontal and vertical encryption simultaneously, the positions of the repeatedly scanned scan lines can be obtained, and the laser can be controlled to emit based on these positions.

[0086] The process of obtaining the position of the repeated scan lines and controlling the laser to emit light based on the position of the repeated scan lines includes:

[0087] The system obtains the position of the scan line in the repeated scan; based on the position of the scan line, it identifies the laser in the current emission group corresponding to that scan line; and controls the laser to emit according to a preset emission time. It is understood that the preset emission time is equal to the emission time of the current emission group plus a preset jitter time. The preset jitter time can be set according to requirements.

[0088] It is understood that when the repeated scan is performed n times, and n > 1, the number of repeated scans is set to have the same number of jitter times as the number of repeated scans. That is, if the repeated scan is performed n times, it includes n jitter times. The lengths of the n jitter times are not equal. They can be random jitter times or can be set as needed.

[0089] Figure 10 An example is shown where N = 4, N′ = 3, and n = 2. The point cloud density in the vertical direction of the central region can be seen as follows: The point cloud density in the horizontal direction is Therefore, by controlling N ′ With n, vertical and horizontal resolution can be controlled.

[0090] S204, the lidar is in a mode where one transmitter corresponds to multiple receivers. The point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor. The scan line interval of each transmitter group is obtained; the third product of the number of scan lines in each transmitter group and the scan line interval of each transmitter group is calculated; the fourth product of the encryption factor of the vertical resolution and the encryption factor of the horizontal resolution is calculated. The horizontal point cloud encryption factor is divisible by the product of the number of scan lines in each transmitter group and the number of receivers corresponding to each transmitter; the vertical point cloud encryption factor is a prime number that is not divisible by the product of the number of scan lines in each transmitter group and the number of receivers corresponding to each transmitter; the quotient of the third product and the fourth product is calculated to obtain the scan line interval corresponding to two adjacent transmissions.

[0091] Understandably, this application is for one-to-many (denoted as n)mul The multi-connection mode is also compatible. The most typical characteristic of the one-to-many connection mode is that each scan line group has n lines. mul They are closely connected because one emitted light spot corresponds to several receivers. This situation is a generalization from interpolation. As shown above, in the case of interpolation, with N groups of emitters and an interval of δθ, if the scanning step is taken as...

[0092]

[0093] In this case, one shot is used for n. mul The connection pattern, and keep n mul When the receivers are arranged vertically, the angular spacing of each nearest neighbor receiver channel is:

[0094]

[0095] By using the interpolation scanning method, the point cloud density (i.e., the minimum resolution) in the vertical direction of the central detection field of view can be improved to δθ′, such as... Figure 10 As shown.

[0096] Furthermore, following the previous description, the point cloud density in the horizontal direction of the central detection field of view can be further encrypted.

[0097] At this point, n should be selected as Nn. mul Divisible. In this case, the step-by-step method is:

[0098]

[0099] This allows for the formation of a point cloud density in the vertical direction at the center of the entire image. A scan line with a horizontal point cloud density increased by n times (e.g.) Figure 11 (As shown on the left); in the example shown in the diagram below, we take N = 4, N ′ Since n is not divisible by N, we choose 3. For illustration, n... mul Choosing the simplest option, 2, results in Nn. mul =8. Choose n=2 (divisible by 8). The central region of the diagram ultimately forms a vertical resolution of δθ / (N). ′ *n mul =δθ / 6, the horizontal resolution of the ROI region is improved by n = 2 times.

[0100] To further explain, Figure 12 A set of scan lines following the same principle but with a slightly more complex design was drawn. At this point:

[0101] N = 5

[0102] N ′ =4 (not divisible by N)

[0103] n mul =3 (depending on send / receive mode)

[0104] n = 3 (Nn) mul =A number divisible by 15)

[0105] It can be seen that the central region forms a vertical point cloud density of δθ / (4*3)=δθ / 12, while the horizontal point cloud density is tripled by the scan line group. Furthermore, it can be observed that the horizontal point cloud density of the scan lines evolves from a 3-fold increase to a 2-fold increase and then gradually evolves to be consistent with other locations, i.e., progressive densification. This can be understood as follows: when horizontal and vertical densification are performed simultaneously, the position of the horizontal densification (i.e., the repeated scan lines) can be obtained, and the laser emission can be controlled based on the position of the repeated scan lines.

[0106] The process of obtaining the position of the repeated scan lines and controlling the laser to emit light based on the position of the repeated scan lines includes:

[0107] The system obtains the position of the scan line in the repeated scan; based on the position of the scan line, it identifies the laser in the current emission group corresponding to that scan line; and controls the laser to emit according to a preset emission time. It can be understood that the preset emission time is equal to the emission time of the current emission group plus a preset jitter time. The preset jitter time can be randomly encoded or set according to requirements.

[0108] It is understood that when a single scan line is scanned repeatedly n times, and n > 1, the same number of jitter times as the number of repeated scans are set. That is, if the scan is repeated n times, it includes n jitter times. The lengths of the n jitter times are unequal. They can be random jitter times or set as needed.

[0109] By setting the jitter time for repeated scanning, the horizontal position of each repeated scan can be staggered by a preset position when the scanning devices of the same dimension are moving at the same speed, thus achieving horizontal encryption.

[0110] Optionally, when there are n overlapping scan lines in the same emission, where n>1, and each line is repeated the same number of times, the same jitter time can also be set for the lasers corresponding to the n overlapping scan lines in the same emission.

[0111] S205, scan according to the scan line interval corresponding to the two adjacent transmissions.

[0112] For details, please refer to S103, which will not be repeated here.

[0113] By adopting the embodiments of this application, the point cloud encryption factor of each level of detection field of view is obtained, and the scan line interval corresponding to two adjacent transmissions is obtained based on the point cloud encryption factor. Scanning is performed according to the scan line interval corresponding to two adjacent transmissions. While satisfying human eye safety, the encryption of ROI can be achieved by controlling the scan line interval corresponding to two adjacent transmissions, thereby improving the efficiency of lidar detection. At the same time, it is also compatible with the one-to-many mode, has a wide range of applications, and is convenient for large-scale commercial use.

[0114] As another optional embodiment, the method of using one n mul The connection pattern, and keep n mul When the receivers are arranged horizontally, as shown above, in the case of interpolation, with N groups of transmitters and an interval of δθ, if the scan step is taken as...

[0115]

[0116] Therefore, in the vertical direction, a point cloud density can be formed at the center of the entire image, which is: Horizontal point cloud density enhancement (nn) mul The increased number of scan lines can better address the problem of low repetition rate in radar transmission and further enhance the radar's ranging capability.

[0117] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0118] Please see Figure 13 This illustration shows a schematic diagram of a point cloud encryption device provided in an exemplary embodiment of this application. The point cloud encryption device can be implemented as all or part of a lidar system through software, hardware, or a combination of both. The lidar system includes a transmitter group and a scanning device, and the device 1 includes an encryption multiplier acquisition module 11, an interval calculation module 12, and a scanning module 13.

[0119] The encryption multiplier acquisition module 11 is used to acquire the encryption multiplier of the point cloud at each level of the detection field of view;

[0120] The interval calculation module 12 is used to obtain the scan line interval corresponding to two adjacent transmissions based on the point cloud encryption multiple of the detection field of view at each level.

[0121] The scanning module 13 is used to scan according to the scan line interval corresponding to the two adjacent transmissions.

[0122] Optionally, the lidar operates on a one-to-one transmit / receive mode, the point cloud encryption factor includes a horizontal point cloud encryption factor or a vertical point cloud encryption factor, and the interval calculation module 12 is specifically used for:

[0123] Obtain the scan line interval for each emission group;

[0124] Calculate the product of the number of scan lines in each emission group and the scan line interval of each emission group, and calculate the quotient of the product with the horizontal point cloud encryption factor or the vertical point cloud encryption factor to obtain the scan line interval corresponding to two adjacent emission events.

[0125] Optionally, the lidar operates on a one-to-one transmit / receive mode, the point cloud encryption factor includes horizontal and vertical point cloud encryption factors, and the interval calculation module 12 is specifically used for:

[0126] Obtain the scan line interval for each emission group;

[0127] Calculate the first product of the number of scan lines in each emission group and the scan line interval of each emission group;

[0128] Calculate the second product of the horizontal point cloud encryption factor and the vertical point cloud encryption factor;

[0129] The quotient of the first product and the second product is calculated to obtain the scan line interval corresponding to two adjacent transmissions.

[0130] Optionally, the lidar is in a mode where one transmitter corresponds to multiple receivers. The point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor. The interval calculation module 12 is specifically used to: obtain the scan line interval of each group of transmitters.

[0131] Calculate the third product of the number of scan lines in each emission group and the scan line interval of each emission group;

[0132] Calculate the fourth product of the encryption factor of the vertical resolution and the encryption factor of the horizontal resolution. The encryption factor of the horizontal point cloud is divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter. The encryption factor of the vertical point cloud is a prime number that is not divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter.

[0133] The quotient of the third product and the fourth product is calculated to obtain the scan line interval corresponding to two adjacent emission times.

[0134] Optionally, the lidar includes a first scanning direction and a second scanning direction, and the spacing of the scanning lines is achieved by scanning with a scanning device in the first scanning direction. The scanning module 13 is specifically used for:

[0135] If the angle of change of the light in one scanning cycle in the second direction is greater than the detection field of view set in the second direction, then the difference between the angle of change of the light in one scanning cycle in the second direction and the detection field of view set in the second direction is calculated.

[0136] Calculate the quotient of the difference and the scanning speed in the second direction to obtain the time corresponding to the two adjacent emission intervals corresponding to the scanning line interval;

[0137] The transmitting group emits detection lasers to the scanning device according to the specified time, and the scanning device emits the detection lasers to the detection field of view for scanning.

[0138] Optionally, when the scanning device moves at a constant speed in the second direction, the scanning speed in the second direction is the constant speed of the scanning device; when the scanning device moves at a non-constant speed in the second direction, the scanning speed in the second direction is the average speed of the scanning device in the second direction.

[0139] It should be noted that the point cloud encryption device provided in the above embodiments is only illustrated by the division of the above functional modules when executing the point cloud encryption method. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the point cloud encryption device and the point cloud encryption method embodiments provided in the above embodiments belong to the same concept, and the implementation process is detailed in the method embodiments, which will not be repeated here.

[0140] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0141] By adopting the embodiments of this application, the point cloud encryption factor of each level of detection field of view is obtained, and the scan line interval corresponding to two adjacent transmissions is obtained based on the point cloud encryption factor. Scanning is performed according to the scan line interval corresponding to two adjacent transmissions. While satisfying human eye safety, the encryption of ROI can be achieved by controlling the scan line interval corresponding to two adjacent transmissions, thereby improving the efficiency of lidar detection. At the same time, it is also compatible with the one-to-many mode, has a wide range of applications, and is convenient for large-scale commercial use.

[0142] This application also provides a computer storage medium that can store multiple instructions, which are adapted to be loaded and executed by a processor as described above. Figures 2-11 The method steps of the illustrated embodiment can be found in the following documentation for detailed execution. Figures 2-11 The specific details of the illustrated embodiments will not be elaborated here.

[0143] This application also provides a lidar that stores at least one instruction, which is loaded and executed by the processor as described above. Figures 2-11 The method steps of the illustrated embodiment can be found in the following documentation for detailed execution. Figures 2-13 The specific details of the illustrated embodiments will not be elaborated here.

[0144] Please see Figure 14 The diagram below provides a structural schematic of a lidar according to an embodiment of this application. Figure 12 As shown, the lidar 1000 may include: at least one processor 1001, at least one network interface 1004, a user interface 1003, a memory 1005, and at least one communication bus 1002.

[0145] The communication bus 1002 is used to realize the connection and communication between these components.

[0146] The user interface 1003 may include a display screen and a camera. Optionally, the user interface 1003 may also include a standard wired interface and a wireless interface.

[0147] The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0148] The processor 1001 may include one or more processing cores. The processor 1001 connects to various parts within the LiDAR 1000 using various interfaces and lines, and performs various functions and processes data of the electronic device 1000 by running or executing instructions, programs, code sets, or instruction sets stored in the memory 1005, and by calling data stored in the memory 1005. Optionally, the processor 1001 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 1001 may integrate one or a combination of several of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU primarily handles the operating system, user interface, and applications; the GPU is responsible for rendering and drawing the content to be displayed on the screen; and the modem handles wireless communication. It is understood that the modem may also not be integrated into the processor 1001 and may be implemented as a separate chip.

[0149] The memory 1005 may include random access memory (RAM) or read-only memory. Optionally, the memory 1005 may include a non-transitory computer-readable storage medium. The memory 1005 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 1005 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the above-described method embodiments, etc.; the data storage area may store data involved in the above-described method embodiments, etc. Optionally, the memory 1005 may also be at least one storage device located remotely from the aforementioned processor 1001. Figure 12 As shown, the memory 1005, which serves as a computer storage medium, may include an operating system, a network communication module, a user interface module, and an encrypted application for point cloud density.

[0150] exist Figure 14 In the lidar 1000 shown, the user interface 1003 is mainly used to provide an input interface for the user and to acquire the user's input data; while the processor 1001 can be used to call the encryption program for generating point cloud density stored in the memory 1005, and specifically perform the following operations:

[0151] Obtain the point cloud encryption factor for each level of the detection field of view;

[0152] Based on the point cloud encryption factor of each level of detection field of view, the scan line interval corresponding to two adjacent transmissions is obtained;

[0153] Scanning is performed according to the scan line interval corresponding to two adjacent transmissions.

[0154] In one embodiment, the lidar operates on a one-to-one transmission and reception mode, and the point cloud encryption factor includes a horizontal point cloud encryption factor or a vertical point cloud encryption factor. When the processor 1001 executes the operation of obtaining the scan line interval corresponding to two adjacent transmissions based on each of the point cloud encryption factors, it specifically performs the following operations:

[0155] Obtain the scan line interval for each emission group;

[0156] Calculate the product of the number of scan lines in each emission group and the scan line interval of each emission group, and calculate the quotient of the product with the horizontal point cloud encryption factor or the vertical point cloud encryption factor to obtain the scan line interval corresponding to two adjacent emission events.

[0157] In one embodiment, the lidar operates on a one-to-one transmission and reception mode, and the point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor. When the processor 1001 executes the operation of obtaining the scan line interval corresponding to two adjacent transmissions based on each of the point cloud encryption factors, it specifically performs the following operations:

[0158] Obtain the scan line interval for each emission group;

[0159] Calculate the first product of the number of scan lines in each emission group and the scan line interval of each emission group;

[0160] Calculate the second product of the horizontal point cloud encryption factor and the vertical point cloud encryption factor;

[0161] The quotient of the first product and the second product is calculated to obtain the scan line interval corresponding to two adjacent transmissions.

[0162] In one embodiment, the lidar operates on a mode where one transmitter corresponds to multiple receivers. The point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor. When the processor 1001 executes the operation of obtaining the scan line interval corresponding to two adjacent transmissions based on each of the point cloud density encryption factors, it specifically performs the following operations:

[0163] Obtain the scan line interval for each emission group;

[0164] Calculate the third product of the number of scan lines in each emission group and the scan line interval of each emission group;

[0165] Calculate the fourth product of the encryption factor of the vertical resolution and the encryption factor of the horizontal resolution. The encryption factor of the horizontal point cloud is divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter. The encryption factor of the vertical point cloud is a prime number that is not divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter.

[0166] The quotient of the third product and the fourth product is calculated to obtain the scan line interval corresponding to two adjacent emission times.

[0167] In one embodiment, the lidar includes a first scanning direction and a second scanning direction. The interval between the scanning lines is achieved by scanning with a scanning device in the first scanning direction. When the processor 1001 performs scanning according to the scanning line interval corresponding to two adjacent transmissions, it specifically performs the following operations:

[0168] If the angle of change of the light in one scanning cycle in the second direction is greater than the detection field of view set in the second direction, then the difference between the angle of change of the light in one scanning cycle in the second direction and the detection field of view set in the second direction is calculated.

[0169] Calculate the quotient of the difference and the scanning speed in the second direction to obtain the time corresponding to the two adjacent emission intervals corresponding to the scanning line interval;

[0170] The transmitting group emits detection lasers to the scanning device according to the specified time, and the scanning device emits the detection lasers to the detection field of view for scanning.

[0171] In one embodiment, when the scanning device moves at a constant speed in the second direction, the scanning speed in the second direction is the constant speed of the scanning device; when the scanning device moves at a non-constant speed in the second direction, the scanning speed in the second direction is the average speed of the scanning device in the second direction.

[0172] By adopting the embodiments of this application, the point cloud encryption factor of each level of detection field of view is obtained, and the scan line interval corresponding to two adjacent transmissions is obtained based on the point cloud encryption factor. Scanning is performed according to the scan line interval corresponding to two adjacent transmissions. While satisfying human eye safety, the encryption of ROI can be achieved by controlling the scan line interval corresponding to two adjacent transmissions, thereby improving the efficiency of lidar detection. At the same time, it is also compatible with the one-to-many mode, has a wide range of applications, and is convenient for large-scale commercial use.

[0173] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory, or random access memory, etc. The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, equivalent variations made according to the claims of this application are still within the scope of this application.

Claims

1. A method of encrypting a point cloud, the method comprising: Applied to lidar, the lidar comprising a transmitter assembly and a scanning device, the method includes: Obtain the point cloud encryption factor for each level of the detection field of view; Based on the point cloud encryption factor of each level of detection field of view, the interval between scan line groups corresponding to two adjacent transmissions is obtained; Scanning is performed according to the interval between the scan line groups corresponding to two adjacent transmissions; The lidar includes a first scanning direction and a second scanning direction. The interval between groups of scan lines corresponding to two adjacent transmissions is achieved by scanning with a scanning device in the first scanning direction. Scanning according to the interval between groups of scan lines corresponding to two adjacent transmissions includes: If the angle of change of the light in one scanning cycle in the second direction is greater than the detection field of view set in the second direction, then calculate the difference between the angle of change of the light in one scanning cycle in the second direction and the detection field of view set in the second direction; calculate the quotient of the difference and the scanning speed in the second direction to obtain the time of the two adjacent emission corresponding to the interval between the scanning line groups; The transmitter group emits detection lasers to the scanning device according to the time interval between two adjacent emissions, and the scanning device emits the detection lasers to the detection field of view for scanning.

2. The method of claim 1, wherein, The scanning devices in the first scanning direction and the scanning devices in the second scanning direction are controlled independently.

3. The method of claim 1, wherein, The lidar operates on a one-to-one transmission / reception mode. The point cloud encryption factor includes a horizontal point cloud encryption factor or a vertical point cloud encryption factor. The step of obtaining the scan line interval between two adjacent transmissions based on each of the point cloud encryption factors includes: Obtain the scan line interval for each emission group; Calculate the product of the number of scan lines in each emission group and the scan line interval of each emission group, and calculate the quotient of the product with the horizontal point cloud encryption factor or the vertical point cloud encryption factor to obtain the scan line interval corresponding to two adjacent emission events.

4. The method of claim 1, wherein, The lidar operates on a one-to-multiple-receiver mode. The point cloud encryption factor includes a horizontal point cloud encryption factor and a vertical point cloud encryption factor. The step of obtaining the scan line interval between two adjacent transmissions based on each of the point cloud encryption factors includes: Obtain the scan line interval for each emission group; Calculate the third product of the number of scan lines in each emission group and the scan line interval of each emission group; Calculate the fourth product of the vertical point cloud encryption factor and the horizontal point cloud encryption factor. The horizontal point cloud encryption factor is divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter. The vertical point cloud encryption factor is a prime number that is not divisible by the product of the number of scan lines in each transmission group and the number of receivers corresponding to each transmitter. The quotient of the third product and the fourth product is calculated to obtain the scan line interval corresponding to two adjacent emission times.

5. The method of claim 1, wherein, When the scanning device moves at a constant speed in the second direction, the scanning speed in the second direction is the constant speed of the scanning device; when the scanning device moves at a non-constant speed in the second direction, the scanning speed in the second direction is the average speed of the scanning device in the second direction.

6. An apparatus for encrypting a point cloud, the apparatus comprising: Applied to lidar, the lidar includes a transmitter assembly and a scanning device, the device comprising: The encryption multiplier acquisition module is used to acquire the point cloud encryption multiplier for each level of the detection field of view; The interval calculation module is used to obtain the scan line interval between two adjacent transmissions based on the point cloud encryption multiple of each level of detection field of view. The scanning module is used to scan according to the scan line interval corresponding to the two adjacent transmissions; The scanning direction of the scanning module includes a first scanning direction and a second scanning direction. The inter-group interval of the scan lines corresponding to two adjacent transmissions is achieved by scanning the scanning module in the first scanning direction. The scanning module is specifically used for: If the angle of change of the light in one scanning cycle in the second direction is greater than the detection field of view set in the second direction, then calculate the difference between the angle of change of the light in one scanning cycle in the second direction and the detection field of view set in the second direction; calculate the quotient of the difference and the scanning speed in the second direction to obtain the time corresponding to the two adjacent emission corresponding to the scanning line interval; Each group of transmitters emits a detection laser to the scanning module according to the specified time. The scanning module then emits the detection laser to the detection field of view for scanning.

7. The apparatus according to claim 6, characterized in that, The scanning modules in the first scanning direction and the scanning modules in the second scanning direction are controlled independently.

8. A computer storage medium, characterized in that, The computer storage medium stores a plurality of instructions adapted for loading by a processor and executing the method steps as claimed in any one of claims 1-5.

9. A lidar, characterized in that, include: A processor and a memory; wherein the memory stores a computer program adapted to be loaded by the processor and to execute the method steps as claimed in any one of claims 1-5.

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