Point cloud encryption method and device, storage medium and lidar

Abstract

The application discloses a point cloud encryption method and device, a storage medium and a laser radar. The method is applied to the laser radar, the laser radar comprises a transmitter group and a scanning device, and the method comprises the following steps: acquiring a point cloud encryption multiple of each level of a detection field of view; acquiring a scanning line interval corresponding to adjacent two times of emission based on the point cloud encryption multiple of each level of the detection field of view; and scanning according to the scanning line interval corresponding to the adjacent two times of emission. According to the application, the ROI encryption can be realized by controlling the scanning line interval corresponding to the adjacent two times of emission groups while meeting the safety of the human eye, and the detection efficiency of the laser radar is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, and particularly relates to a point cloud encryption method and device, a storage medium and a laser radar. BACKGROUND

[0002] The laser radar can directly and quickly and highly accurately image a three-dimensional space, and thus becomes one of main sensors in the current automatic driving technology. At present, the development of the laser radar mainly develops in the direction of stronger ranging, higher point cloud density and meeting human eye safety laws and regulations. The laser waveband of the vehicle-mounted laser radar is in infrared, mainly including two kinds: 900 nm and 1500 nm. The laser radar of the 1500 nm waveband has a higher human eye safety threshold, but the emission module and the receiving module of this kind of laser radar have a high cost due to material limitation, and it is difficult to be commercially used on a large scale in the medium and short term. As for the 900 nm laser radar, the threshold of human eye safety is low, and under the condition of meeting specific ranging performance, the continuous improvement of the point cloud density is limited.

[0003] How to improve the ranging performance and the detection point cloud density under the condition of ensuring human eye safety becomes a problem to be solved. SUMMARY

[0004] Embodiments of the present application provide a point cloud encryption method and device, a storage medium and a laser radar. The ROI encryption can be realized by controlling the scanning line interval of adjacent two times of emission while meeting human eye safety, the efficiency of laser radar detection is improved, and the technical solution is as follows:

[0005] In a first aspect, an embodiment of the present application provides a point cloud encryption method applied to a laser radar, the laser radar comprising an emitter group and a scanning device, and the method comprises the following steps:

[0006] Obtaining a point cloud encryption multiple of each level of detection field of view;

[0007] Based on the point cloud encryption multiple of each level of detection field of view, obtaining a scanning line interval corresponding to adjacent two times of emission;

[0008] Scanning according to the scanning line interval corresponding to the adjacent two times of emission.

[0009] In a second aspect, an embodiment of the present application provides a point cloud density encryption device applied to a laser radar, the laser radar comprising an emitter group and a scanning device, and the device comprises the following modules:

[0010] A multiple obtaining module, configured to obtain a point cloud encryption multiple of each level of detection field of view;

[0011] An interval calculating module, configured to obtain a scanning line interval corresponding to adjacent two times of emission based on the point cloud encryption multiple of each level of detection field of view.

[0012] a scanning module, configured to scan according to the scanning line interval corresponding to the adjacent two times of emission.

[0013] In a third aspect, an embodiment of the present application provides a computer storage medium, which stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and performing the method steps described above.

[0014] In a fourth aspect, an embodiment of the present application provides a laser radar, which can include a processor and a memory; wherein the memory stores a computer program, and the computer program is suitable for being loaded by the processor and performing the method steps described above.

[0015] The technical scheme provided by some embodiments of the present application has at least the following beneficial effects:

[0016] By adopting the embodiments of the present application, the point cloud encryption multiples of the detection fields at all levels are acquired, the scanning line interval corresponding to the adjacent two times of emission is acquired based on the point cloud encryption multiples, and scanning is performed according to the scanning line interval of the adjacent two times of emission. In this way, the ROI encryption can be realized by controlling the scanning line interval of the adjacent two times of emission while meeting the eye safety, and the efficiency of the laser radar detection is improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

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

[0019] Figure 2 is a flowchart of a point cloud encryption method provided by an embodiment of the present application;

[0020] Figure 3 is an example schematic diagram of acquiring the scanning line interval corresponding to the adjacent two times of emission provided by an embodiment of the present application;

[0021] Figure 4a is a schematic diagram of the arrangement of the emitters in the same emission group provided by an embodiment of the present application;

[0022] Figure 4b is another schematic diagram of the arrangement of the emitters in the same emission group provided by an embodiment of the present 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 diagram illustrating how to improve point cloud density in a single-shot, multi-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 the present application, it is understood that the terms "first", "second" and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance. The specific meaning of the above terms in the present application can be understood by the person skilled in the art according to the specific circumstances. In addition, in the description of the present application, "a plurality of" means two or more than two, unless otherwise specified. The association relationship of the associated objects is described, and it means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. The character " / " generally represents that the associated objects before and after are in an "or" relationship.

[0037] The present application will be described in detail below in conjunction with specific embodiments.

[0038] The laser waveband of the vehicle-mounted laser radar is in the infrared, mainly including two kinds: near 900nm and near 1500nm. The laser radar of the 1500nm waveband has a higher eye safety threshold, but the emission module and the receiving module of this kind of laser radar are high in cost due to material limitations, and it is difficult to be mass-produced in the short term. For the 900nm laser radar, the threshold of eye safety is low, which limits the continuous improvement of the point cloud density under the condition of meeting the specific ranging performance.

[0039] In actual use scenarios, only in the detection field of view close to the vehicle and the road, the laser radar needs to achieve a very high point cloud density, and in other positions, the laser radar needs a lower point cloud density to meet the detection of the surrounding environment. Therefore, the laser radar industry proposes the concept of a region of interest (ROI), which is generally the area that the radar is interested in. The radar generally needs to achieve a high point cloud density in the region of interest (ROI). It can be understood that the laser radar also includes a general detection area, which is the area in the total detection field of view except the region of interest (ROI). Among them, the region of interest (ROI) can also be referred to as the target detection field of view of the laser radar, and the general detection area can also be referred to as the general detection field of view of the laser radar. The sum of the target detection field of view and the general detection field of view is the total detection field of view of the radar.

[0040] The detection field of view of the general laser radar can be divided into vertical and horizontal dimensions. In the general laser radar, the point cloud density is uniformly distributed in the entire detection field of view, such as Figure 1 indicated in the upper left corner, while the ROI includes the following cases: horizontal point cloud density encryption, such as Figure 1 indicated in the upper right corner; vertical point cloud density encryption, such as Figure 1 indicated in the lower left corner; horizontal point cloud density and vertical point cloud density encryption, such as Figure 1 indicated in the lower right corner.

[0041] The present application will be described in detail below in conjunction with specific embodiments. Figure 2- attached Figure 11 The encryption method of the point cloud provided by the embodiment of the application is described in detail. The method can be implemented by relying on a computer program and can run on a point cloud encryption device based on the von Neumann architecture. The computer program can be integrated in an application or run as a standalone tool application. The point cloud encryption device in the embodiment of the application can include but is not limited to a laser radar, a vehicle-mounted device, an airplane, a train, a handheld device, a wearable device, a computing device, or other processing devices connected to a wireless modem, etc. The laser radar includes a transmitter group, a scanning device, a receiving device, and a signal processor.

[0042] Please refer to Figure 2 A flowchart of the point cloud encryption method provided by the embodiment of the application is shown in FIG. 1.

[0043] As Figure 2 shown, the method of the embodiment of the application can include the following steps:

[0044] S101, acquiring point cloud encryption multiples of each level of detection field of view;

[0045] It can be understood that the detection field of view of the laser radar includes a total detection field of view and a target detection field of view, and the target detection field of view is a region of interest (ROI). According to the detection point cloud density requirement of the target detection field of view, the target detection field of view can include at least one level of detection field of view, such as a first level of detection field of view, a second level of detection field of view, etc. It can be understood that the number of the target detection field of view is not limited in the application. For example, the target detection field of view can include a first level of detection field of view, a second level of detection field of view, a third level of detection field of view, …, an n level of detection field of view, etc.

[0046] It can be understood that, as an optional embodiment, the point cloud density of each level of detection field of view can be related to the number of levels of detection field of view, for example, the lower the number of levels, the higher the point cloud density, which changes regularly. For example, the point cloud density of the first level of detection field of view is the highest, the point cloud density of the second level of detection field of view is the second highest, …, and the point cloud density of the n level of detection field of view is the lowest, where n>2. Alternatively, the point cloud density of each level of detection field of view can not be strongly related to the number of levels of detection field of view, that is, as long as the point cloud density of each level of target detection field of view is different. For example, the point cloud density of the first level of detection field of view is the highest, the point cloud density of the n level of detection field of view is the second highest, …, and the point cloud density of the second level of detection field of view is the lowest, n>2. The point cloud density of each level of target detection field of view is different. It can be understood that, as an optional embodiment, the requirement of the point cloud encryption multiple of each level of detection field of view can be different. In an optional embodiment, the first level of detection field of view is a central detection field of view, the second level of detection field of view is a second level of encryption field of view between the central detection field of view and a general detection field of view, and each level of detection field of view corresponds to a corresponding encryption multiple. The encryption multiple can be set according to the current requirement.

[0047] S102, based on the point cloud encryption multiple of each level of detection field of view, obtaining the scanning line interval corresponding to adjacent two times of emission;

[0048] The laser radar can emit N scanning points at a time. It can be understood that when the laser radar includes multiple emission groups, the N scanning points can be emitted by an emission group, or can be N scanning points formed by simultaneous emission of multiple emission groups.

[0049] As an optional embodiment of the present application, when the laser radar includes two scanning directions, the scanning line interval can be realized by scanning of the scanning device in one dimension direction. For example, the laser radar can emit N scanning points at a time, forming N scanning lines, and the scanning line interval is δθ. The rotation speed in the two scanning directions (horizontal direction and vertical direction) is denoted as ω \\ and ω ⊥ . It should be noted that the functions of the two directions can be exchanged. In one scanning period, the angle of light change in the horizontal direction in one scanning period is denoted as α period , the detection field of view in the horizontal direction is denoted as α FOV , and at this time α FOV ≤α period .

[0050] In the vertical direction, the group interval of the scanning lines corresponding to adjacent two times of emission is denoted as δβ. The scanning line interval can be realized by scanning of the scanning device in one dimension direction. For example, in the vertical direction, the scanning device can move at a constant speed in the entire scanning period, as shown in Figure 3 , and at this time, the following can be obtained:

[0051]

[0052] If the angle of light change in the scanning period α period is greater than the detection field of view in the horizontal direction α Fov , the scanning device can quickly rotate through an angle in the non-emission area to realize it, as shown in Figure 3 , and at this time:

[0053]

[0054] Among them, by adjusting the scanning mode of the scanning device in one dimension direction to set δβ, the form of the detection point cloud can be more reasonably set.

[0055] Wherein, it can be understood that the scanning device in one dimension direction can be a rotating mirror, a one-dimensional galvanometer, or a rotating platform, for example; the present application does not limit the scanning device in this dimension. The scanning device in the other dimension can also be a rotating mirror, a one-dimensional galvanometer, or a rotating platform, for example; the present application does not limit the type of scanning device in any dimension. It can be understood that the types of the scanning device in the first dimension and the second dimension can be the same or different, which is not limited by the present application. As a preferred embodiment, the scanning devices in the two dimensions can be independently controlled. It can be understood that a plurality of encryption modes can be combined by reasonably selecting the scanning line interval δθ and the group interval δβ between adjacent two groups of scanning lines. It should be noted that δβ can be achieved by two ways which are not limited to the above description. Wherein, it can be understood that the scanning line interval δθ here can be achieved by setting the interval of the emitter arrangement, or by controlling the interval emission of the laser emitter. It should be noted that the scanning line interval δθ here can be achieved by ways which are not limited to the above description. Wherein, it can be understood that the same emission group can be arranged in a column or in different columns. It can be understood that when the same emission group is arranged in two columns, the δθ can be reduced by arranging all the emitters in the same emission group as shown in Figure 4a as shown in Figure 4b , the emitters in the target area can be partially arranged to reduce δθ, as shown in Figure 4b , the interval of the emitters in the edge area is δθ1, and the interval of the emitters in the center area is δθ2, wherein δθ2≤δθ1. By this design, the point cloud density of the target area can be further improved without changing the interval of the two emission angles. Wherein, it can be understood that when the emitters in the same emission group are arranged in a column, the interval of the emitters in the edge area and the interval of the emitters in the center area can be set to be different, so as to achieve a denser point cloud in the target area. As shown in Figure 4c , the interval between the edge emitters in the same emission group is δθ1, and the interval between the center emitters is δθ2, wherein δθ2≥δθ1. Wherein, it can be understood that the angle interval of the emitters in the emission group and the number of groups of the scanning can be determined according to the point cloud density requirements of the target field of view and the edge field of view.

[0056] The transmitter can be a vertical-cavity surface-emitting laser (VCSEL) or an edge-emitting laser (EEL), and can alternatively be a fiber laser light emitting device. The application does not limit the type of transmitter. It can be understood that the multiple transmitting groups can be arranged in one column or in different columns, and the application does not limit the arrangement of the multiple transmitting groups. As an optional embodiment, the intervals of the lasers in different transmitting groups can be the same or different, and the application does not limit this.

[0057] Specifically, if the laser radar is in a one-transmitting-one-receiving mode, that is, one transmitting corresponds to one receiving, the point cloud density includes a horizontal resolution or a vertical resolution, and the scanning line interval δθ of each transmitting group is obtained; the product of the number N of scanning lines of each level of detection field of view and the scanning line interval δθ of each transmitting group is calculated, the quotient of the product and the encryption multiple n of the point cloud density is calculated, and the scanning line interval of the adjacent two transmissions is obtained, The scanning line interval of the adjacent two transmissions refers to the interval of the first scanning line of each transmission. It can be understood that when the two transmissions are the scanning line intervals of two transmissions of the same transmitting group, the scanning interval is the step amount of the scanning device in the first direction. It can be understood that the horizontal or vertical encryption can be realized by setting the step amount of the scanning device in the same direction.

[0058] Further, when the transmitting interval is fixed, the vertical or horizontal encryption can be realized by setting the encryption multiple and the number of transmitters corresponding to the same transmitting group.

[0059] It can be understood that when the scanning line interval of each transmitting group is determined, the encryption multiple n is a prime number that cannot be divided by the number N of transmitters of the same transmitting group, and the scanning line interval of the two transmissions can realize vertical encryption.

[0060] It can be understood that when the scanning line interval of each transmitting group is determined, the encryption multiple n is an integer that can be divided by the number N of transmitters of the same transmitting group, and the scanning line interval of the two transmissions can realize horizontal encryption.

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

[0062] According to the scanning line interval corresponding to the adjacent two transmissions set above, scanning can be realized to realize the horizontal and / or vertical point cloud encryption.

[0063] It can be understood that when the interval of the scanning lines corresponding to the two emissions can be achieved by scanning of the scanning device in a dimension direction, and the adjacent two emissions are the scanning line intervals of the two emissions of the same emission group, the scanning interval is the step amount of the scanning device in the dimension.

[0064] Among them, it can be understood that the same emission group can be a column of lasers, or a row of lasers, can be two columns of lasers, or two rows of lasers, and the present application is not limited to the arrangement form of the lasers of the same emission group.

[0065] The laser radar includes a first scanning direction and a second scanning direction, the interval of the scanning lines is achieved by scanning of the scanning device in the first scanning direction, if the angle of the light change in a scanning period in the second direction is greater than the detection field of view angle set in the second direction, the difference between the angle of the light change in a scanning period in the second direction and the detection field of view angle 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 adjacent two emissions corresponding to the scanning line interval; the emission group emits detection laser to the scanning device according to the time, and the scanning device emits the detection laser 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 the present application, the encryption multiple of the point cloud of each level of detection field of view is obtained, the scanning line interval corresponding to the adjacent two emissions is obtained based on the point cloud encryption multiple of each level of detection field of view, and scanning is performed according to the scanning line interval corresponding to the adjacent two emissions, so that the ROI region can be encrypted by controlling the scanning line interval corresponding to the adjacent two emissions while meeting the eye safety, and the efficiency of laser radar detection is improved.

[0068] Please refer to Figure 5 , a flowchart of a point cloud encryption method provided by the embodiments of the present application. As Figure 5 shown, the point cloud encryption method can include the following steps:

[0069] S201, obtaining the point cloud encryption multiple of each level of detection field of view;

[0070] The number of scanning lines emitted by the emission group is based on the performance of the emission group itself, for example, the number of scanning lines of each emission group is N, and the interval between every two scanning 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 scanning point distribution is increased in the horizontal direction, thereby increasing the point cloud density in the horizontal direction. It should be noted that through the control of the emission time, the point cloud density in the horizontal direction can be increased by several times through several repetitions in the horizontal direction. That is, by controlling the positions of the two scans to be unchanged and changing the time interval of the scans, the encryption multiple in the horizontal direction can be changed.

[0078] When n = 2, only the middle group is encrypted, and at this time, the horizontal resolution of the ROI region is doubled. When n > 2, the resolution of the center region is n times the original. The ROI region extends from the center to the edge, and the resolution gradually changes to n-1 times, n-2 times, n-3 times, and finally transitions to the original resolution. As an illustrative description, Figure 7 The scanning line characteristics of n = 2 and n = 3 are shown.

[0079] Figure 8 The vertical direction encryption method is shown in FIG. 8. For N scanning lines with an interval of δθ, when δβ is Nδθ, the two groups of scanning lines in the vertical direction are offset. The arrows represent the change in the vertical direction angle in different scanning processes.

[0080] In S203, the laser radar is a transmission corresponding to a receiving mode, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, the scanning line interval of each transmission group is obtained; a first product of the number of scanning lines of each transmission group and the scanning line interval of each transmission group is calculated; a second product of the horizontal point cloud encryption multiple and the vertical point cloud encryption multiple is calculated; and a quotient of the first product and the second product is calculated to obtain a scanning line interval corresponding to adjacent two transmissions.

[0081] On the basis of the above-mentioned horizontal density improvement, the interpolation method can also be compatible, so that the vertical and horizontal densities of the center detection field of view can be improved at the same time.

[0082] First, the interpolation method is briefly described. As shown in FIG. 9, a group of scanning lines emitted by a laser at different times are shown, and are marked as A, B, C, and D. It is assumed that the number of scanning lines is N (i.e., the number of emitters in each transmission group), and the scanning line interval is δθ. With the change of time, the scanning lines are scanned downward, moving from A to B, C, and D (arrow mark) gradually, and each time moving downward by N. Figure 9 On the basis of the interpolation method, the scanning interval can be set as:

[0083]

[0084]

[0085] ​Wherein,'is the number of vertical encryption times, n is the number of horizontal encryption times, N is the number of transmitters, and n is a number that N can be divided by. At this time, in the central area, in addition to the inserted scan lines, each group of scan lines will be additionally repeated n times, and it can be understood that when horizontal and vertical encryption are performed at the same time, the position of the repeatedly scanned scan lines can be obtained, and the laser emitter is controlled to emit light according to the position of the repeatedly scanned scan lines.

[0086] Wherein, the position of the repeatedly scanned scan lines is obtained, and the laser emitter is controlled to emit light according to the position of the repeatedly scanned scan lines, including:

[0087] The position of the repeatedly scanned scan lines is obtained, and the laser emitter corresponding to the scan line of the current emission group is obtained according to the position of the repeatedly scanned scan lines; and the laser emitter is controlled to emit light 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 set according to requirements.

[0088] It can be understood that when the number of repeated scanning is n times and n>1, the number of repeated scanning is set to be the same as the number of jitter times, that is, if the number of repeated scanning is n times, n jitter times are included. The lengths of the n jitter times are not equal. They can be random jitter times or set according to requirements.

[0089] Figure 10 An example is shown, in which N=4, N'=3, and n=2. It can be seen that the point cloud density in the central area in the vertical direction is The point cloud density in the horizontal direction is Therefore, by controlling N ′ and n, the control of the vertical and horizontal resolutions can be realized.

[0090] S204, the laser radar is a mode of emitting corresponding to multiple receiving, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, the scan line interval of each emission group is obtained; the third product of the number of scan lines of each emission group and the scan line interval of each emission group is calculated; the fourth product of the encryption multiple of the vertical resolution and the encryption multiple of the horizontal resolution is calculated, the horizontal point cloud encryption multiple is divided by the product of the number of scan lines of each emission group and the number of receivers corresponding to each emitter; the vertical point cloud encryption multiple is a prime number that is not divided by the product of the number of scan lines of each emission group and the number of receivers corresponding to each emitter; the quotient of the third product and the fourth product is calculated to obtain the scan line interval corresponding to adjacent two times of emission.

[0091] It can be understood that the present application is one-to-many (denoted as nmul ) receiving mode is also compatible. The most typical feature of the one-to-many mode is that each group of scan lines is n mul closely connected, because one emitting spot corresponds to several receiving. This case is a generalization of the interpolation method. As shown above, in the case of interpolation method, N groups of emitting, with interval δθ, if the scan step is taken as

[0092]

[0093] In this case, the one-to-n mul receiving mode is adopted, and n mul is kept as n

[0094]

[0095] By following the scanning method of the interpolation 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', as shown in Figure 10 .

[0096] Further, following the foregoing, the point cloud density in the horizontal direction of the central detection field of view can be encrypted again.

[0097] At this time, n should be selected as Nn mul integer. At this time, the step is taken as:

[0098]

[0099] The scanning line (as shown in the left of ) can be formed in the center of the full image, with the point cloud density in the vertical direction being Figure 11 and the point cloud density in the horizontal direction being improved by n times. In the following example of the schematic diagram, we take N = 4, which is not an integer of N ′ , so 3 is selected. As an illustration, n mul is selected as the simplest 2, at this time Nn mul = 8. n = 2 (which can be divided by 8) is selected. The center area of the schematic diagram finally forms a ROI area with the vertical resolution being δθ / (N ′ *n mul ) = δθ / 6, and the horizontal resolution being improved by n = 2 times.

[0100] In order to further illustrate, Figure 12 a set of slightly more complex scanning lines following the same principle are drawn, at this time:

[0101] N = 5

[0102] N ′ = 4 (which cannot be an integer of N)

[0103] n mul = 3 (depending on the transceiving mode)

[0104] n = 3 (Nn mul = 15 can be divided by the number)

[0105] It can be seen that the central region forms a vertical point cloud density of δθ / (4*3) = δθ / 12, and the horizontal point cloud density of the scan line group is 3 times. In addition, it can be seen that the horizontal point cloud density of the scan line evolves from 3 times to 2 times and then gradually evolves to be consistent with other positions, that is, gradual encryption. It can be understood that when horizontal and vertical encryption are performed at the same time, the position of horizontal encryption (i.e., the repeated scan line) can be obtained, and the laser is controlled to emit according to the position of the repeated scan line.

[0106] Wherein, the position of the repeated scan line is obtained, and the laser is controlled to emit according to the position of the repeated scan line, comprising:

[0107] The position of the repeated scan line is obtained; the laser corresponding to the emission group of the current emission of the scan line is obtained according to the position of the repeated scan line; and the laser is controlled to emit according to the preset emission time. It can be understood that the preset emission time is equal to the emission time of the emission group this time plus a preset jitter time. The preset jitter time can be random coding or can be set according to requirements.

[0108] It can be understood that when the number of repeated scans of the single scan line is n times, and n>1, the same number of jitter times as the number of repeated scans is set according to the number of repeated scans, that is, if the repeated scan is n times, and includes n jitter times. The lengths of the n jitter times are not equal. It can be a random jitter time, or it can be set according to requirements.

[0109] By setting the jitter time of repeated scanning, the horizontal position of each repeated scan can be staggered by a preset position under the condition that the same dimension scanning device is synchronized with the same amount of progress, so as to realize horizontal encryption.

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

[0111] S205, scanning according to the interval between the scan lines corresponding to the adjacent two emissions.

[0112] For details, see S103, which will not be repeated here.

[0113] By adopting the embodiment of the present application, the point cloud encryption multiples of each level of detection field of view are acquired, the scanning line interval corresponding to adjacent two times of emission is acquired based on the point cloud encryption multiples, and scanning is performed according to the scanning line interval corresponding to the adjacent two times of emission, so that the ROI encryption can be realized by controlling the scanning line interval corresponding to the adjacent two times of emission while meeting the eye safety, the efficiency of laser radar detection is improved, and meanwhile, the one-to-multiple receiving mode can be compatible, the application range is wide, and large-scale commercial use is facilitated.

[0114] As another optional embodiment, the one-to-n mul receiving mode is adopted, and the n mul When the receiving is horizontally arranged, as shown above, in the case of interpolation method, if the scanning step is taken as

[0115]

[0116] then the point cloud density in the vertical direction can be formed as in the full image center, and the point cloud density in the horizontal direction is improved by n mul times of scanning lines, so that the problem of low radar emission repetition frequency can be better solved, and the ranging capability of the radar is further improved.

[0117] The following is an apparatus embodiment of the present application, which can be used to execute the method embodiments of the present application. For details not disclosed in the apparatus embodiments of the present application, refer to the method embodiments of the present application.

[0118] Please refer to Figure 13 , which shows the structure schematic diagram of a point cloud encryption device provided by an example embodiment of the present application. The point cloud encryption device can be realized by software, hardware or a combination of both to become all or part of a laser radar. The laser radar includes a transmitter group and a scanning device, and the device 1 includes an encryption multiple acquisition module 11, an interval calculation module 12 and a scanning module 13.

[0119] The encryption multiple acquisition module 11 is configured to acquire the point cloud encryption multiples of each level of detection field of view.

[0120] The interval calculation module 12 is configured to acquire the scanning line interval corresponding to adjacent two times of emission based on the point cloud encryption multiples of each level of detection field of view.

[0121] The scanning module 13 is configured to perform scanning according to the scanning line interval corresponding to the adjacent two times of emission.

[0122] Optionally, the laser radar is a mode of one emission corresponding to one reception, the point cloud encryption multiple includes a horizontal point cloud encryption multiple or a vertical point cloud encryption multiple, and the interval calculation module 12 is specifically configured to:

[0123] obtain a scan line interval of each emission group;

[0124] calculate a product of a number of scan lines of the each emission group and the scan line interval of the each emission group, calculate a quotient of the product and the horizontal point cloud encryption multiple or the vertical point cloud encryption multiple, and obtain a scan line interval corresponding to adjacent two emissions.

[0125] Optionally, the laser radar is a mode of one emission corresponding to one reception, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and the interval calculation module 12 is specifically configured to:

[0126] obtain a scan line interval of each emission group;

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

[0128] calculate a second product of the horizontal point cloud encryption multiple and the vertical point cloud encryption multiple;

[0129] calculate a quotient of the first product and the second product, and obtain a scan line interval corresponding to adjacent two emissions.

[0130] Optionally, the laser radar is a mode of one emission corresponding to multiple receptions, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and the interval calculation module 12 is specifically configured to obtain a scan line interval of each emission group;

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

[0132] calculate a fourth product of an encryption multiple of the vertical resolution and an encryption multiple of the horizontal resolution, the horizontal point cloud encryption multiple is an integer multiple of a product of the number of scan lines of the each emission group and a number of receivers corresponding to the each emitter, and the vertical point cloud encryption multiple is a prime number that is not an integer multiple of the product of the number of scan lines of the each emission group and the number of receivers corresponding to the each emitter;

[0133] calculate a quotient of the third product and the fourth product, and obtain a scan line interval corresponding to adjacent two emissions.

[0134] Optionally, the laser radar includes a first scanning direction and a second scanning direction, the scan line interval is realized through scanning of a scanning device in the first scanning direction, and the scanning module 13 is specifically configured to:

[0135] if the angle of the light ray change in the second direction in one scanning period is greater than the set detection field of view angle in the second direction, then calculate the difference between the angle of the light ray change in the second direction in one scanning period and the set detection field of view angle in the second direction;

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

[0137] the emission group emits the detection laser to the scanning device according to the time, and the scanning device emits the detection laser to the detection field of view for scanning.

[0138] Optionally, when the scanning device moves at a uniform speed in the second direction, the scanning speed in the second direction is the uniform speed of the scanning device; when the scanning device moves at a non-uniform speed in the second direction, the scanning speed in the second direction is the average movement 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 used to execute the point cloud encryption method, and only the division of the above functional modules is used as an example for illustration. In actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is 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 provided in the above embodiments belong to the same concept, and the implementation process is described in detail in the method embodiments, which will not be repeated here.

[0140] The serial numbers of the above embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0141] By adopting the embodiments of the present application, the point cloud encryption multiples of the detection fields of view at all levels are obtained, the scanning line intervals corresponding to the adjacent two times of emission are obtained based on the point cloud encryption multiples, and scanning is performed according to the scanning line intervals corresponding to the adjacent two times of emission. While meeting the safety of the human eye, the ROI encryption can be realized by controlling the scanning line intervals corresponding to the adjacent two times of emission, the efficiency of the laser radar detection is improved, and the one-shot multi-receiving mode is also compatible, which has a wide range of applications and is convenient for large-scale commercial use.

[0142] The embodiments of the present application also provide a computer storage medium, which can store a plurality of instructions, the instructions being suitable for being loaded and executed by a processor to perform the method steps of the embodiments as shown in the above Figures 2-11 The specific execution process can be referred to the specific description of the embodiments as shown in the above Figures 2-11 The specific execution process can be referred to the specific description of the embodiments as shown in the above

[0143] The application also provides a laser radar which stores at least one instruction loaded and executed by the processor, and the at least one instruction is used for executing the method steps of the above embodiments Figures 2-11 The specific implementation process can be referred to the specific description of the above embodiments Figures 2-13 The specific implementation process can be referred to the specific description of the above embodiments

[0144] Please refer to Figure 14 The application provides a structural schematic diagram of a laser radar. As shown in Figure 12 The laser radar 1000 can 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 the components.

[0146] The user interface 1003 can include a display screen (Display) and a camera (Camera). Optionally, the user interface 1003 can also include a standard wired interface and a wireless interface.

[0147] The network interface 1004 can optionally include a standard wired interface and a wireless interface (such as a WI-FI interface).

[0148] The processor 1001 can include one or more processing cores. The processor 1001 connects various parts in the laser radar 1000 through various interfaces and lines, executes various functions of the electronic device 1000 and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 1005, and calling data stored in the memory 1005. Optionally, the processor 1001 can be realized in at least one of the following hardware forms: Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA). The processor 1001 can be integrated with a combination of one or more of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU is mainly used to process operating systems, user interfaces, and application programs. The GPU is used to render and draw the content to be displayed on the display screen. The modem is used to process wireless communication. It can be understood that the above-mentioned modem can also not be integrated into the processor 1001, but can be realized by 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 laser radar is one emission corresponding to one receiving mode, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and the processor 1001 specifically performs the following operations when performing the acquisition of the scanning line interval corresponding to the adjacent two emissions based on each of the point cloud encryption multiples:

[0158] acquiring the scanning line interval of each emission group;

[0159] calculating a first product of the number of scanning lines of each emission group and the scanning line interval of each emission group;

[0160] calculating a second product of the horizontal point cloud encryption multiple and the vertical point cloud encryption multiple;

[0161] calculating a quotient of the first product and the second product to obtain the scanning line interval corresponding to the adjacent two emissions.

[0162] In one embodiment, the laser radar is one emission corresponding to multiple receptions, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and the processor 1001 specifically performs the following operations when performing the acquisition of the scanning line interval corresponding to the adjacent two emissions based on each of the point cloud encryption multiples:

[0163] acquiring the scanning line interval of each emission group;

[0164] calculating a third product of the number of scanning lines of each emission group and the scanning line interval of each emission group;

[0165] calculating a fourth product of the encryption multiple of the vertical resolution and the encryption multiple of the horizontal resolution, the horizontal point cloud encryption multiple being divided by the product of the number of scanning lines of each emission group and the number of receivers corresponding to each emitter; and the vertical point cloud encryption multiple being a prime number that is not divided by the product of the number of scanning lines of each emission group and the number of receivers corresponding to each emitter;

[0166] calculating a quotient of the third product and the fourth product to obtain the scanning line interval corresponding to the adjacent two emissions.

[0167] In one embodiment, the laser radar includes a first scanning direction and a second scanning direction, the scanning line interval is realized by scanning of a scanning device in the first scanning direction, and the processor 1001 specifically performs the following operations when performing the scanning according to the scanning line interval corresponding to the adjacent two emissions:

[0168] if the angle of the light changing in one scanning period in the second direction is greater than the detection field of view angle set in the second direction, calculate the difference between the angle of the light changing in one scanning period in the second direction and the detection field of view angle set in the second direction;

[0169] calculate the quotient of the difference and the scanning speed in the second direction, to obtain the time corresponding to the scanning line interval corresponding to the adjacent two emissions;

[0170] the emission group emits the detection laser to the scanning device according to the time, and the scanning device emits the detection laser to the detection field of view for scanning.

[0171] In an 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 using the embodiments of the present application, the point cloud encryption multiples of the detection fields of view at all levels are obtained, the scanning line intervals corresponding to the adjacent two emissions are obtained based on the point cloud encryption multiples, and scanning is performed according to the scanning line intervals corresponding to the adjacent two emissions. In this way, the ROI encryption can be realized by controlling the scanning line intervals corresponding to the adjacent two emissions while meeting the safety of the human eye, the efficiency of the laser radar detection is improved, and the one-emission-multiple-reception mode can be compatible, which has a wide application range and is convenient for large-scale commercial use.

[0173] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware, and the program can be stored in a computer readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments. The storage medium can be a magnetic disc, an optical disc, a read-only memory or a random access memory, etc. The above-mentioned only discloses the preferred embodiments of the present application, and of course cannot limit the scope of the rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope of the present application.

Claims

1. A method of encrypting a point cloud, the method comprising: The method is applied to a laser radar, the laser radar comprises a transmitting group and a scanning device, and the method comprises the following steps: Obtaining a point cloud encryption multiple of each level of detection field of view; Based on the point cloud encryption multiple of each level of detection field of view, obtaining a scanning line interval corresponding to adjacent two times of transmission; According to the scanning line interval corresponding to the adjacent two times of transmission, scanning is performed; wherein the scanning line interval corresponding to the adjacent two times of transmission is realized by scanning of the scanning device in one dimension direction, and the scanning line interval corresponding to the adjacent two times of transmission is the scanning line interval of two times of transmission of the same transmitting group; the scanning line interval corresponding to the adjacent two times of transmission is the stepping amount of the scanning device in the dimension direction; The laser radar is a mode of one transmission corresponding to multiple reception, the point cloud encryption multiple comprises a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and based on the point cloud encryption multiple of each level of detection field of view, the scanning line group interval corresponding to the adjacent two times of transmission is obtained, comprising: Obtaining a scanning line interval of each group of transmitting groups; Calculating a third product of the number of scanning lines of each group of transmitting groups and the scanning line interval of each group of transmitting groups; Calculating a fourth product of the vertical point cloud encryption multiple and the horizontal point cloud encryption multiple, the horizontal point cloud encryption multiple is divided by the product of the number of scanning lines of each group of transmitting groups and the number of receivers corresponding to each transmitter; the vertical point cloud encryption multiple is a prime number which is not divided by the product of the number of scanning lines of each group of transmitting groups and the number of receivers corresponding to each transmitter; calculating the quotient of the third product and the fourth product to obtain the scanning line group interval corresponding to the adjacent two times of transmission; The interval between adjacent transmitters corresponding to the edge field of view in each group of transmitting groups is not equal to the interval between adjacent transmitters corresponding to the central field of view.

2. The method of claim 1, wherein, The scanning line interval is the interval of the arrangement of the transmitters in each group of transmitting groups or the transmission interval formed by controlling the transmitters in each group of transmitting groups to perform interval transmission.

3. The method of claim 1, wherein, The laser radar comprises a first scanning direction and a second scanning direction, the scanning line interval is realized by scanning of the scanning device in the first scanning direction, and the scanning according to the scanning line interval corresponding to the adjacent two times of transmission comprises: If the angle of light change in one scanning period in the second direction is greater than the set detection field of view angle in the second direction, the difference between the angle of light change in one scanning period in the second direction and the set detection field of view angle 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 scanning line interval corresponding to the adjacent two times of transmission; Each group of transmitting groups emits detection laser to the scanning device according to the time, and the scanning device emits the detection laser to the detection field of view for scanning.

4. The method of claim 3, 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 movement speed of the scanning device in the second direction.

5. An apparatus for encrypting a point cloud, the apparatus comprising: The device is applied to a laser radar, the laser radar comprises a transmitter group and a scanning device, and the device comprises: An encryption multiple obtaining module is configured to obtain point cloud encryption multiples of each level of detection field of view; An interval calculating module is configured to obtain a scanning line interval corresponding to adjacent two times of emission based on the point cloud encryption multiples of each level of detection field of view; A scanning module is configured to perform scanning according to the scanning line interval corresponding to the adjacent two times of emission; wherein the scanning line interval corresponding to the adjacent two times of emission is implemented by scanning of a scanning device in one dimension direction, and the scanning line interval corresponding to the adjacent two times of emission is a scanning line interval of two times of emission of the same emission group; the scanning line interval corresponding to the adjacent two times of emission is a stepping amount of the scanning device in the dimension direction; The laser radar is in a mode of one emission corresponding to multiple receptions, the point cloud encryption multiple includes a horizontal point cloud encryption multiple and a vertical point cloud encryption multiple, and the interval calculating module is specifically configured to: obtain a scanning line interval of each emission group; calculate a third product of a scanning line number of each emission group and the scanning line interval of each emission group; calculate a fourth product of the vertical point cloud encryption multiple and the horizontal point cloud encryption multiple, the horizontal point cloud encryption multiple is divided by a product of the scanning line number of each emission group and a number of receivers corresponding to each emitter; the vertical point cloud encryption multiple is a prime number that is not divided by the product of the scanning line number of each emission group and the number of receivers corresponding to each emitter; and calculate a quotient of the third product and the fourth product to obtain a scanning line group interval corresponding to adjacent two times of emission. Intervals between adjacent emitters corresponding to edge fields of view in the each emission group are not equal to an interval between adjacent emitters corresponding to a center field of view.

6. A computer storage medium, characterized in that The computer storage medium stores a plurality of instructions, the instructions being suitable for being loaded and executed by a processor to perform the method steps of any one of claims 1-4.

7. A lidar, comprising: The computer storage medium stores a plurality of instructions, the instructions being suitable for being loaded and executed by a processor to perform the method steps of any one of claims 1-4. The computer storage medium stores a plurality of instructions, the instructions being suitable for being loaded and executed by a processor to perform the method steps of any one of claims 1-4. The computer storage medium stores a plurality of instructions, the instructions being suitable for being loaded and executed by a processor to perform the method steps of any one of claims 1-4.

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