CN115035206B

CN115035206B - Compression method, decompression method and related device of laser point cloud

Info

Publication number: CN115035206B
Application number: CN202210497782.9A
Authority: CN
Inventors: 林辉; 卢维; 王政; 李铭
Original assignee: Zhejiang Huaray Technology Co Ltd
Current assignee: Zhejiang Huaray Technology Co Ltd
Priority date: 2022-05-09
Filing date: 2022-05-09
Publication date: 2024-03-29
Anticipated expiration: 2042-05-09
Also published as: CN115035206A

Abstract

The application provides a compression method, a decompression method and a related device of laser point cloud, and relates to the technical field of automatic navigation. The compression method is characterized in that a target straight line is determined in a laser point cloud frame based on the position of a laser scanning point in the laser point cloud frame, and each region is obtained based on the division of the target straight line, so that the compression information of the laser point cloud frame is determined to be first compression information corresponding to each target straight line and second compression information corresponding to each region, wherein the first compression information corresponding to the target straight line comprises the straight line information of the target straight line and the start-stop point cloud serial number of the laser scanning point positioned on the target straight line; the second compressed information corresponding to the region comprises the scanning distance and the start-stop point cloud serial number of each laser scanning point in the region. The method has the advantages that the calculated amount of straight line extraction is small, the realization is simple, and the point cloud information on the straight line can be greatly reduced, so that the compression cost and the compression data volume can be greatly reduced, the compression efficiency is improved, and the efficient compression of the laser point cloud is realized.

Description

Compression method, decompression method and related device of laser point cloud

Technical Field

The embodiment of the application relates to the technical field of automatic navigation, in particular to a compression method, a decompression method and a related device of laser point cloud.

Background

2D laser navigation is a key technology in an automatic navigation vehicle (Automated Guided Vehicle, AGV), as the application requirements of mobile robots are continuously increased, the number of robot devices adopting 2D laser navigation is increased, the running time of an execution task is longer, the data volume of 2D laser point clouds is also increased, and the storage and transmission requirements of a large amount of point cloud data are higher and higher to the compression and decompression of the 2D laser point clouds.

Currently, a laser point cloud compression method is generally adopted, namely, the laser point cloud is firstly converted into an image or video, and then the image or video is compressed by adopting a traditional image/video compression algorithm. However, the data volume of the laser point cloud is generally smaller than that of an image or video, and the compression cost of the image/video compression algorithm is high, so that the compression cost for compressing the laser point cloud by adopting the method is high, and the compression efficiency is low.

Disclosure of Invention

In order to solve the existing technical problems, the embodiment of the application provides a compression method, a decompression method and a related device of laser point cloud, which can improve the compression efficiency of compressing the laser point cloud and reduce the compression cost.

In order to achieve the above purpose, the technical solution of the embodiments of the present application is implemented as follows:

in a first aspect, an embodiment of the present application provides a method for compressing a laser point cloud, where the method includes:

determining a target straight line in a laser point cloud frame based on the positions of laser scanning points in the laser point cloud frame, wherein the number of the laser scanning points on the target straight line is larger than a first set number threshold, the point cloud serial numbers of the laser scanning points on the target straight line are continuous, the point cloud serial numbers of the laser scanning points are set based on a scanning sequence, and the laser scanning points on different target straight lines are different;

taking the first compression information corresponding to each target straight line and the second compression information corresponding to each region as compression information of the laser point cloud frame, wherein the regions are obtained by dividing based on the target straight lines, and the first compression information corresponding to the target straight lines comprises the straight line information of the target straight lines, the point cloud serial number maximum value and the point cloud serial number minimum value of laser scanning points positioned on the target straight lines; the second compressed information corresponding to the region comprises a scanning distance, a point cloud serial number maximum value and a point cloud serial number minimum value of each laser scanning point in the region; the scanning distance of the laser scanning point is the distance between the laser scanning point and a laser emitting device of the laser radar.

According to the compression method of the laser point cloud, the target straight line can be extracted from the laser point cloud frame based on the position of the laser scanning point in the laser point cloud frame, the laser point cloud frame is compressed according to the extracted target straight line to obtain compression information of the laser point cloud frame, the compression information comprises first compression information corresponding to each target straight line and second compression information corresponding to each region, the regions are obtained based on the division of the target straight line, and the first compression information corresponding to the target straight line comprises the straight line information of the target straight line, the point cloud serial number maximum value and the point cloud serial number minimum value of the laser scanning point located on the target straight line; the second compressed information corresponding to the region comprises a scanning distance, a point cloud serial number maximum value and a point cloud serial number minimum value of each laser scanning point in the region. Because the calculated amount of the linear extraction is small and the realization is simple, the laser point cloud is compressed in a linear extraction mode, so that the compression cost can be greatly reduced and the compression efficiency is improved; and when the laser scanning points positioned on the straight line are compressed, only the point cloud serial number maximum value and the point cloud serial number minimum value of the laser scanning points positioned on the straight line and the straight line information of the straight line are reserved in the obtained compressed information, so that the data volume is greatly reduced, and the efficient compression is realized.

In an alternative embodiment, the determining the target straight line in the laser point cloud frame based on the position of the laser scanning point in the laser point cloud frame includes:

dividing laser scanning points included in a laser point cloud frame into a plurality of point cloud sets, wherein each laser scanning point is located in one point cloud set, and the point cloud sets comprise the laser scanning points with continuous sequence numbers;

determining a target straight line corresponding to a target point cloud set aiming at the target point cloud set with the number of laser scanning points larger than a second set number threshold, wherein the target straight line is a straight line with the minimum sum of the distances between the laser scanning points included in the target point cloud set; or the target straight line is the straight line containing the most laser scanning points in the target point cloud set.

In this embodiment, the laser scanning points included in the laser point cloud frame may be divided into a plurality of point cloud sets, and then a target straight line corresponding to the target point cloud set may be determined from any one of the target point cloud sets including laser scanning points whose number is greater than the second set number threshold, where the target straight line may be a straight line having a minimum sum of distances between the target point cloud set and each of the laser scanning points included in the target point cloud set, or may be a straight line including the largest number of the laser scanning points in the target point cloud set. Therefore, more target straight lines which are more in number and more in accordance with the set requirements can be extracted from the laser point cloud frame.

In an alternative embodiment, the dividing the laser scanning points included in the laser point cloud frame into a plurality of point cloud sets includes:

taking laser scanning points included in the laser point cloud frame as a point cloud set, and circularly executing the following operations until the point cloud set with the number of the laser scanning points smaller than a second set number threshold exists:

determining a fitting straight line in the point cloud set by a least square method according to the positions of the laser scanning points in the point cloud set, and determining a target scanning point meeting a set distance condition according to the distance between each laser scanning point in the point cloud set and the fitting straight line;

dividing the laser scanning points positioned before the point cloud serial numbers of the target scanning points into one point cloud set, and dividing the laser scanning points positioned after the point cloud serial numbers of the target scanning points into the other point cloud set.

In this embodiment, the laser scanning points included in the laser point cloud frame may be taken as one point cloud set, and then the following operations are performed in a loop until there is a point cloud set in which the number of laser scanning points is smaller than the second set number threshold value: according to the positions of the laser scanning points in the point cloud set, a fitting straight line is determined in the point cloud set through a least square method, according to the distance between each laser scanning point included in the point cloud set and the fitting straight line, a target scanning point meeting a set distance condition is determined, the laser scanning point before the point cloud serial number of the target scanning point and the target scanning point are divided into one point cloud set, and the laser scanning point after the point cloud serial number of the target scanning point is divided into another point cloud set. Therefore, the laser scanning points included in the laser point cloud frame can be reasonably divided into corresponding point cloud sets, and when the target straight line is extracted from the divided point cloud sets, the more suitable target straight line can be extracted.

In an optional embodiment, the line information of the target line includes a line parameter and a line sequence number, and the line sequence number included in the line information of the target line is set based on the sequence of the collected laser point cloud frames; or (b)

The target straight line comprises a collinear straight line and a non-collinear straight line, the straight line information of the non-collinear straight line comprises a straight line parameter and a straight line serial number, and the straight line information of the collinear straight line comprises a corresponding straight line serial number of the non-collinear straight line;

wherein the collinear line of the target lines is determined by:

randomly selecting one laser point cloud frame from a plurality of continuous laser point cloud frames as a key frame, and taking other laser point cloud frames in the plurality of continuous laser point cloud frames as common frames, wherein the linear sequence number included in the linear information of the non-collinear line is set based on the sequence of the collected laser point cloud frames in the plurality of laser point cloud frames;

and taking a target straight line which meets a set collineation condition with at least one target straight line included in the key frame as a collineation straight line from among target straight lines included in the normal frame, wherein the target straight line which meets the set collineation condition with the collineation straight line is a non-collineation straight line corresponding to the collineation straight line.

In this embodiment, when compressing a single laser point cloud frame, the line information of the target line included in the first compressed information corresponding to the target line in the obtained compressed information may include a line parameter and a line sequence number, and the line sequence number included in the line information of the target line is set based on the order of the collected laser point cloud frames. When compressing the continuous plurality of laser point cloud frames, the extracted target straight line may include a collinear straight line and a non-collinear straight line, the straight line information of the non-collinear straight line included in the first compression information corresponding to the non-collinear straight line in the obtained compression information may include a straight line parameter and a straight line sequence number, and the straight line information of the collinear straight line included in the first compression information corresponding to the collinear straight line may include a straight line sequence number of the corresponding non-collinear straight line. The collinear line is a target line satisfying a set collinear condition with at least one target line included in a key frame in a plurality of continuous laser point cloud frames, among target lines included in a normal frame in the plurality of continuous laser point cloud frames. When the continuous multiple laser point cloud frames are compressed, straight lines included in the common frames in the continuous multiple laser point cloud frames are fused with straight lines included in the key frames in the continuous multiple laser point cloud frames, and the straight lines in the common frames meeting the collineation condition are removed from the compressed information, so that the number of the extracted straight lines can be reduced, the data volume is further reduced, and the compression efficiency is improved.

In an optional embodiment, the setting, as the collinear line, a target line that satisfies a set collinear condition with at least one target line included in the key frame, from among target lines included in the normal frame, includes:

for each target straight line included in the normal frame, the following operations are performed:

projecting a target straight line included in the common frame to a reference frame of the key frame, and respectively determining the distance between the target straight line included in the common frame and at least one target straight line included in the key frame;

and if the distance between the target straight line included in the normal frame and the key target straight line in the at least one target straight line included in the key frame meets the set threshold condition, taking the target straight line included in the normal frame as a collinear straight line.

In this embodiment, by projecting each target straight line included in the normal frame respectively under the reference frame of the key frame and determining the distance between the target straight line included in the normal frame and at least one target straight line included in the key frame respectively, when the distance between one target straight line included in the normal frame and the key target straight line included in the key frame satisfies the set threshold condition, the target straight line included in the normal frame may be regarded as a collinear straight line. By calculating the distance between the straight line in the normal frame and the straight line in the key frame, the target straight line collinear with the straight line in the key frame can be determined in the normal frame, so that the straight line fusion can be completed, the straight line in the normal frame meeting the collinearly condition is removed from the compressed information, and the number of the extracted straight lines is reduced.

In an alternative embodiment, the set threshold condition is that the first point-line distance is less than a second set threshold distance, and the second point-line distance is less than the second set threshold distance;

the first point line distance is the distance between a laser scanning point corresponding to the maximum value of the point cloud serial numbers positioned on the target straight line included by the common frame and the key target straight line; the second wire distance is the distance between the laser scanning point corresponding to the minimum value of the point cloud serial number positioned on the target straight line included in the common frame and the key target straight line.

In this embodiment, the threshold condition is that the first point-line distance is less than the second set threshold distance and the second point-line distance is less than the second set threshold distance. The first point line distance is the distance between a laser scanning point corresponding to the maximum value of the point cloud serial numbers positioned on a target straight line included in the common frame and a key target straight line; the second wire distance is the distance between the laser scanning point corresponding to the minimum value of the point cloud serial number positioned on the target straight line included in the common frame and the key target straight line. Since it is possible to determine whether or not two straight lines are collinear based on only the point-to-straight line distance, the amount of calculation complexity in determining that two straight lines are collinear is reduced, and the realization of calculation is simple and quick.

In a second aspect, an embodiment of the present application provides a method for decompressing a laser point cloud, where the method includes:

acquiring compression information of a laser point cloud frame; the compression information comprises first compression information corresponding to each target straight line and second compression information corresponding to each region; the target straight line is determined in the laser point cloud frame by the compression end based on the position of the laser scanning point in the laser point cloud frame; the region is divided based on the target straight line;

determining the point cloud serial number of each laser scanning point on the target straight line according to the point cloud serial number maximum value and the point cloud serial number minimum value of the laser scanning point on the target straight line, determining the scanning angle corresponding to the point cloud serial number of each laser scanning point on the target straight line according to the association relation between the point cloud serial number and the scanning angle of each laser scanning point, and determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line information of the target straight line and the scanning angle of each laser scanning point; and

and determining the point cloud serial numbers of all the laser scanning points in the area according to the point cloud serial numbers of the laser scanning points in the area and the point cloud serial numbers of the laser scanning points in the area, determining the scanning angles corresponding to the point cloud serial numbers of all the laser scanning points in the area according to the association relation, and determining the positions of all the laser scanning points in the area in the laser point cloud frame based on the determined scanning angles and the scanning distances of all the laser scanning points included in the second compressed information.

According to the decompression method of the laser point cloud, after compression information of the laser point cloud frame is obtained, the point cloud serial numbers of the laser scanning points on the target straight line can be determined according to the point cloud serial number maximum value and the point cloud serial number minimum value of the laser scanning points on the target straight line, which are included in first compression information corresponding to each target straight line in the compression information, and the scanning angles corresponding to the point cloud serial numbers of the laser scanning points on the target straight line are determined according to the association relation between the point cloud serial numbers of the laser scanning points and the scanning angles, and the positions of the laser scanning points on the target straight line in the laser point cloud frame are determined based on the straight line information of the target straight line and the scanning angles of the laser scanning points; and determining the point cloud serial numbers of the laser scanning points in the area according to the point cloud serial numbers of the laser scanning points in the area and the point cloud serial numbers of the laser scanning points in the area, which are included in the second compressed information corresponding to the areas in the compressed information, determining the scanning angles corresponding to the point cloud serial numbers of the laser scanning points in the area according to the association relation, and determining the positions of the laser scanning points in the area in the laser point cloud frame based on the determined scanning angles and the scanning distances of the laser scanning points included in the second compressed information. Because each laser scanning point in the laser point cloud frame can be obtained by decompression from the compression information corresponding to the straight line or the compression information corresponding to the area according to the point cloud segmentation type of the laser point cloud, the decompression of the laser point cloud can be efficiently and rapidly completed.

In an alternative embodiment, the determining the position of each laser scanning point located on the target straight line in the laser point cloud frame based on the straight line information of the target straight line and the scanning angle of each laser scanning point includes:

if the straight line information of the target straight line comprises a straight line parameter and a straight line serial number, determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line parameter of the target straight line and the scanning angle of each laser scanning point;

and if the straight line information of the target straight line comprises a straight line serial number, determining that the target straight line is a collinear straight line, determining straight line parameters of the non-collinear straight line according to the non-collinear straight line corresponding to the straight line serial number, and determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line parameters of the non-collinear straight line and the scanning angles of each laser scanning point, wherein a set collinearly condition is met between the collinear straight line and the corresponding non-collinear straight line.

In this embodiment, if the line information of the target line includes the line parameter and the line number, the position of each laser scanning point located on the target line in the laser point cloud frame may be determined based on the line parameter of the target line and the scanning angle of each laser scanning point; if the straight line information of the target straight line comprises the straight line serial number, determining that the target straight line is a collinear straight line, determining straight line parameters of the non-collinear straight line according to the non-collinear straight line corresponding to the straight line serial number, and determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line parameters of the non-collinear straight line and the scanning angle of each laser scanning point. When the straight line information comprises the straight line parameter and the straight line serial number, the first compressed information of the straight line corresponding to the straight line information can be directly decompressed; when the straight line information only comprises the straight line serial number, the straight line corresponding to the straight line information can be determined to be a collinear straight line, and the straight line parameter of the non-collinear straight line is obtained according to the non-collinear straight line corresponding to the straight line serial number, so that decompression of the first compressed information corresponding to the collinear straight line is completed based on the straight line parameter, and the decompression efficiency of the laser point cloud is further improved.

In a third aspect, an embodiment of the present application further provides a compression device for a laser point cloud, including:

a straight line extraction unit, configured to determine a target straight line in a laser point cloud frame based on a position of a laser scanning point in the laser point cloud frame, where the number of laser scanning points on the target straight line is greater than a first set number threshold, and point cloud serial numbers of the laser scanning points on the target straight line are continuous, the point cloud serial numbers of the laser scanning points are set based on a scanning order, and laser scanning points on different target straight lines are different;

the information compression unit is used for taking first compression information corresponding to each target straight line and second compression information corresponding to each region as compression information of the laser point cloud frame, wherein the regions are obtained by dividing the target straight lines, and the first compression information corresponding to the target straight lines comprises the straight line information of the target straight lines, the point cloud serial number maximum value and the point cloud serial number minimum value of laser scanning points on the target straight lines; the second compressed information corresponding to the region comprises a scanning distance, a point cloud serial number maximum value and a point cloud serial number minimum value of each laser scanning point in the region; the scanning distance of the laser scanning point is the distance between the laser scanning point and a laser emitting device of the laser radar.

In an alternative embodiment, the straight line extracting unit is further configured to:

wherein the collinear line of the target lines is determined by:

In an alternative embodiment, the information compression unit is further configured to:

In a fourth aspect, an embodiment of the present application further provides a decompression device for a laser point cloud, including:

the information acquisition unit is used for acquiring compression information of the laser point cloud frame; the compression information comprises first compression information corresponding to each target straight line and second compression information corresponding to each region; the target straight line is determined in the laser point cloud frame by the compression end based on the position of the laser scanning point in the laser point cloud frame; the region is divided based on the target straight line;

an information decompression unit, configured to determine, according to a point cloud serial number maximum value and a point cloud serial number minimum value of laser scanning points located on the target straight line and included in the first compressed information, a point cloud serial number of each laser scanning point on the target straight line, determine, according to an association relationship between the point cloud serial number and a scanning angle of each laser scanning point, a scanning angle corresponding to the point cloud serial number of each laser scanning point located on the target straight line, and determine, based on straight line information of the target straight line and the scanning angle of each laser scanning point, a position of each laser scanning point located on the target straight line in the laser point cloud frame; and

In an alternative embodiment, the information decompression unit is specifically configured to:

In a fifth aspect, embodiments of the present application further provide a computer readable storage medium, where a computer program is stored, where the computer program is executed by a processor to implement the method for compressing a laser point cloud according to the first aspect.

In a sixth aspect, an embodiment of the present application further provides an electronic device, including a memory and a processor, where the memory stores a computer program that can be executed on the processor, and when the computer program is executed by the processor, causes the processor to implement the method for compressing a laser point cloud in the first aspect.

In a seventh aspect, embodiments of the present application further provide a computer readable storage medium, where a computer program is stored, where the computer program, when executed by a processor, implements the decompression method of the laser point cloud of the second aspect.

In an eighth aspect, an embodiment of the present application further provides an electronic device, including a memory and a processor, where the memory stores a computer program that can be executed on the processor, and when the computer program is executed by the processor, the processor is caused to implement the decompression method of the laser point cloud of the second aspect.

Technical effects caused by any implementation manner of the third aspect, the fifth aspect and the sixth aspect may refer to technical effects caused by corresponding implementation manners of the first aspect, which are not described herein.

Technical effects caused by any implementation manner of the fourth aspect, the seventh aspect and the eighth aspect may be referred to technical effects caused by corresponding implementation manners of the second aspect, and are not described herein.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a flowchart of a compression method of a laser point cloud according to an embodiment of the present application;

fig. 2 is a schematic diagram of determining a target straight line in a laser point cloud frame according to an embodiment of the present application;

fig. 3 is a flowchart of another compression method of a laser point cloud according to an embodiment of the present application;

fig. 4 is a flowchart of a decompression method of a laser point cloud according to an embodiment of the present application;

Fig. 5 is a flowchart of another decompression method of a laser point cloud according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a compression device for laser point cloud according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a decompression device of a laser point cloud according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the present application more apparent, the present application will be described in further detail below with reference to the accompanying drawings, wherein it is apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

It should be noted that the terms "comprises" and "comprising," along with their variants, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The following describes in detail the technical solutions provided in the embodiments of the present application with reference to the accompanying drawings.

The embodiment of the application provides a compression method of laser point cloud, as shown in fig. 1, comprising the following steps:

step S101, determining a target straight line in the laser point cloud frame based on the position of the laser scanning point in the laser point cloud frame.

The number of laser scanning points on the target straight line is larger than a first set number threshold, the point cloud serial numbers of the laser scanning points on the target straight line are continuous, the point cloud serial numbers of the laser scanning points are set based on the scanning sequence, and the laser scanning points on different target straight lines are different.

Specifically, the laser scanning points included in the laser point cloud frame may be taken as one point cloud set, and the following operations are performed in a circulating manner until there is a point cloud set in which the number of laser scanning points is smaller than the second set number threshold value:

determining a fitting straight line in the point cloud set by a least square method according to the positions of the laser scanning points in the point cloud set, and determining target scanning points meeting the set distance condition according to the distances between each laser scanning point in the point cloud set and the fitting straight line; dividing the laser scanning points positioned before the point cloud serial numbers of the target scanning points into one point cloud set, and dividing the laser scanning points positioned after the point cloud serial numbers of the target scanning points into the other point cloud set.

The least squares method is a mathematical optimization technique. It finds the best functional match for the data by minimizing the sum of squares of the errors. The linear equation parameters can be calculated using the least square method, and the sum of squares of errors between these calculated data and actual data is minimized. The least square is to fit n points, so that the total error of the points from the fitting straight line is as small as possible. The solution method is to minimize the vertical error from each point to the straight line.

Each laser scanning point is located in one point cloud set, and the point cloud set comprises the laser scanning points with continuous sequence numbers.

After dividing the laser scanning points included in the laser point cloud frame into a plurality of point cloud sets, determining a target straight line corresponding to the target point cloud set according to the target point cloud set, wherein the target straight line is the straight line with the smallest sum of the distances between the laser scanning points included in the target point cloud set, or the target straight line is the straight line containing the largest number of the laser scanning points in the target point cloud set, for the target point cloud set, wherein the number of the laser scanning points included in any one of the target point cloud sets is larger than a second set number threshold.

Step S102, taking first compression information corresponding to each target straight line and second compression information corresponding to each region as compression information of a laser point cloud frame, wherein the first compression information corresponding to the target straight line comprises straight line information of the target straight line, a point cloud serial number maximum value and a point cloud serial number minimum value of a laser scanning point positioned on the target straight line; the second compressed information corresponding to the region comprises a scanning distance, a point cloud serial number maximum value and a point cloud serial number minimum value of each laser scanning point in the region.

The area is obtained based on the division of the target straight line, and the scanning distance of the laser scanning point is the distance between the laser scanning point and the laser emitting device of the laser radar.

For example, as shown in fig. 2, the laser point cloud frame includes 39 laser scanning points in total, and numbers near each laser scanning point in fig. 2 indicate the point cloud numbers of the corresponding laser scanning points, and the point cloud numbers are set according to the scanning order of the laser scanning points. By the above-mentioned straight line determination mode, 3 target straight lines of L1, L2 and L3 can be determined in the laser point cloud frame, and based on this, the laser scanning points in the laser point cloud frame can be divided into 3 target straight lines and 2 areas respectively, namely, the laser scanning points 1-13 can be divided into the area 1, the laser scanning points 14-23 can be divided into the target straight line L1, the laser scanning points 24-29 can be divided into the target straight line L2, the laser scanning points 30-33 can be divided into the area 2, and the laser scanning points 34-39 can be divided into the target straight line L3.

Then, respectively scanning the laser points in 3 target straight lines and 2 areas to obtain compression information of the laser point cloud frame, wherein the second compression information corresponding to the area 1 comprises scanning distances of the laser scanning points 1-13, 1 and 13; the first compression information corresponding to the target straight line L1 includes the straight line information, 14, and 23 of the target straight line L1; the first compression information corresponding to the target straight line L2 includes the straight line information, 24, and 29 of the target straight line L2; the second compressed information corresponding to the area 2 includes the scanning distance of the laser scanning points 30-33, 30 and 33; the first compression information corresponding to the target straight line L3 includes the straight line information, 34, and 39 of the target straight line L3.

The straight line information of the target straight line comprises a straight line parameter and a straight line sequence number, and the straight line sequence number of the target straight line is set based on the sequence of the acquired laser point cloud frames. Alternatively, the target straight line includes a collinear straight line and a non-collinear straight line, the straight line information of the non-collinear straight line includes a straight line parameter and a straight line number, and the straight line information of the collinear straight line includes a straight line number of the corresponding non-collinear straight line.

Wherein the collinear line of the target lines is determined by:

randomly selecting one laser point cloud frame from the continuous multiple laser point cloud frames as a key frame, and taking other laser point cloud frames in the continuous multiple laser point cloud frames as common frames, wherein the line serial numbers included in the line information of the non-collinear lines are set based on the sequence of the collected laser point cloud frames in the multiple laser point cloud frames;

projecting a target straight line included in the common frame to a reference frame of the key frame, and respectively determining the distance between the target straight line included in the common frame and at least one target straight line included in the key frame; if the distance between the target straight line included in the common frame and the key target straight line in the at least one target straight line included in the key frame meets the set threshold condition, the target straight line included in the common frame is taken as a collinear straight line;

The target straight line satisfying the set collineation condition with respect to the common straight line is a non-collinear straight line corresponding to the collinear straight line.

For example, the normal frame includes 3 target straight lines A1, A2 and A3, the key frame includes 3 target straight lines B1, B2 and B3, the target straight lines A1, A2 and A3 are respectively projected under the reference frame of the key frame, and distances d11, d12 and d13 between the target straight line A1 and the target straight lines B1, B2 and B3 are respectively determined; distances d21, d22, and d23 between the target straight line A2 and the target straight line B1, the target straight line B2, and the target straight line B3, respectively; distances d31, d32, and d33 between the target straight line A3 and the target straight line B1, the target straight line B2, and the target straight line B3, respectively. If the distance d11 between the target straight line A1 and the target straight line B1 satisfies the set threshold condition, it is possible to determine that the target straight line A1 is collinear with the target straight line B1 and to set the target straight line A1 as a collinear line of the target straight line B1.

The threshold condition is that the first point-line distance is less than the second set threshold distance and the second point-line distance is less than the second set threshold distance. The first point line distance is the distance between a laser scanning point corresponding to the maximum value of the point cloud serial numbers positioned on a target straight line included in the common frame and a key target straight line; the second wire distance is the distance between the laser scanning point corresponding to the minimum value of the point cloud serial number positioned on the target straight line included in the common frame and the key target straight line.

In some embodiments, the laser point cloud compression method provided by the application is suitable for an AGV of 2D laser navigation, and the running environment is an indoor structured environment. AGVs are typically equipped with 2D lasers, wheel odometers, inertial measurement units (Inertial Measurement Unit, IMU) for computing position and position, which can output the pose of each frame of laser point cloud under the same map reference systemWhere (x, y) is the 2D position and θ is the rotation angle.

Specifically, the compression method of the laser point cloud provided in the embodiment of the present application may also be implemented according to a process shown in fig. 3, where, as shown in fig. 3, the method includes the following steps:

step S301, determining a target straight line in the laser point cloud frame based on the position of the laser scanning point in the laser point cloud frame.

One frame 2D laser point cloud f= { p ₁ ,p ₂ ,…,p _n The laser scanning points are included in the sequence, and each scanning point describes a specific 2D coordinate. Laser point clouds typically have two common coordinate expressions: a cartesian coordinate system and a polar coordinate system. In the embodiment of the application, the laser point cloud may be represented by a polar coordinate system, that is, each laser scanning point in the laser point cloud f may be represented as p _i ＝{θ _i ,r _i And }, where θ _i For the scanning angle, the scanning angle is the angle between the connecting line between the laser scanning point and the laser emitting device of the laser radar and the horizontal plane where the laser emitting device is located, r _i The scanning distance is the distance between the laser scanning point and the laser emitting device of the laser radar. The polar coordinate system can be converted to a Cartesian coordinate system by the following formula:

since lidar is usually scanned with equal angular resolution, the difference between the scan angles corresponding to adjacent laser scan points in the laser point cloud f is a fixed value θ _inc And the start angle θ of the lidar scan _min Angle of termination theta _max Are known. The reference frame fid of the laser point cloud and the scan start angle theta are usually set _min Angle of end of scan theta _max Angle resolution theta _inc Minimum scan distance r _min Maximum scan distance r _max Frame header combined into laser point cloud:H＝{fid,θ _min ,θ _max ,θ _inc ,r _min ,r _max }. Thus, the laser point cloud can also be expressed as f= { h|r ₁ ,r ₂ ,…,r _n }, point p therein _i Is a scanning angle of theta _min +(i-1)·θ _inc 。

And determining a target straight line in the laser point cloud frame according to the position of the laser scanning point in the laser point cloud frame. And the determined target straight line needs to simultaneously meet the following three conditions: the first condition is that laser scanning points on different target straight lines are different; the number of laser scanning points on the target straight line is larger than a first set number threshold value; and thirdly, continuously scanning the point cloud serial numbers of the laser scanning points on the target straight line. The point cloud serial numbers of the laser scanning points in the laser point cloud frame are set based on the scanning sequence.

Since the linear equation of the target straight line is ax+by+c=0, the straight line parameter of the target straight line can be expressed as l= [ a, b, c]Thus, each target straight line determined in the laser point cloud frame can be expressed as { l } ₁ ,l ₂ ,…,l _m }。

Step S302, dividing laser scanning points in the laser point cloud frame into a linear point cloud segment and a nonlinear point cloud segment according to the determined target straight lines, and carrying out intra-frame coding on the laser point cloud frame based on the obtained linear point cloud segment and the obtained nonlinear point cloud segment to obtain compression information of the laser point cloud frame.

After each target straight line in the laser point cloud frame is determined, the laser scanning points on the target straight line and the laser scanning points not on the target straight line can be correspondingly obtained. By utilizing the equal-angle resolution scanning characteristic of the laser point cloud and combining the obtained linear result, all laser scanning points in the laser point cloud frame can be segmented in sequence to obtain f= { s ₁ ,s ₂ ,…,s _h }. Where s represents a segment, comprising two types: a straight line point cloud segment and a non-straight line point cloud segment.

The straight line point cloud segment can be expressed as s _h ＝{i,j|lid _h I, j represents the start sequence number and the end sequence number of the laser scanning point of the segment, and lid _h Representing the segmentA line number of a target line to which the laser scanning point belongs; the non-straight point cloud segment may be represented as s _h ＝{i,j|r _i ,r _i+1 ,…,r _j I, j represents the start sequence number and the end sequence number of the laser scanning point of the segment, r _i Is the scanning distance.

Performing intra-frame encoding on the laser point cloud frame, and obtaining compression information of the laser point cloud frame may be:

f＝{H|l ₁ ,l ₂ ,…,l _m |s ₁ ,s ₂ ,…,s _h }

wherein l _m ＝[a _m ,b _m ,c _m ]，

Step S303, the compressed information of the laser point cloud frame is cached.

Step S304, determining whether the number of the laser point cloud frames continuously cached reaches a set frame number threshold; if yes, go to step S305; if not, step S303 is performed.

Because the compression rate of a single laser point cloud frame is limited, in order to more fully utilize the characteristic of high overlap ratio of laser point clouds in a plurality of continuous laser point cloud frames, the plurality of continuous laser point cloud frames need to be compressed together, so that the compression information of the obtained laser point cloud frames can be buffered first until the number of the laser point cloud frames buffered continuously reaches a set frame number threshold N frame, and then the next operation is performed.

In step S305, one laser point cloud frame is randomly selected from the continuous multiple laser point cloud frames reaching the set frame number threshold as a key frame, and other laser point cloud frames in the continuous multiple laser point cloud frames are used as normal frames.

When the number of the laser point cloud frames continuously cached reaches a set frame number threshold, one laser point cloud frame can be randomly selected from the continuous multiple laser point cloud frames to serve as a key frame, and other laser point cloud frames in the continuous multiple laser point cloud frames serve as common frames.

PreferablyThe first laser point cloud frame can be selected from N laser point cloud frames which are continuously cachedThe frame is denoted as f as a key frame _K The rest frames are common frames and marked as f _t . Wherein key frame f _K The corresponding pose is xi _K Normal frame f _t The corresponding pose is xi _t . And the continuous N laser point cloud frames are recorded as a point cloud group G = { { { zeta ₁ ,f ₁ },…,{ξ _K ,f _K },…,{ξ _N ,f _N }}。

And step S306, respectively carrying out straight line fusion on each target straight line included in the common frame and each target straight line included in the key frame, and determining a straight line fusion result.

In a group of point cloud frames G, as the frames are continuous, the target straight lines between the common frames and the key frames are overlapped, so that straight line fusion can be performed. The method for straight line fusion comprises the following steps:

(1) Acquiring a normal frame f in G _t ；

(2) In the normal frame f _t Internal acquisition of a target lineAnd acquiring a point cloud segment belonging to the target straight line.

Straight line projection of the target onto the keyframe f _K The formula under the reference frame of (2) may be:the polar coordinates of the first and the last two laser scanning points of the point cloud segment belonging to the target straight line are determined +.>And->After that, they can be projected to the key frame f respectively _K Is obtained from the following reference frame:

/>

(3) At key frame f _K Internal acquisition of a target lineAnd calculate +.>Is +. >Distance between them.

First, the laser is scanned to pointAnd->Converting the polar coordinate system into a Cartesian coordinate system to obtain corresponding Cartesian coordinates +.>And->

Then, when the target is straightIs +.>Laser scanning Point->Andto the target straight line->The distance of (2) may be +.>If satisfy d _b <th _overlap ，d _e <th _overlap Condition, then determine->Collinear and added to the collinear lookup Table _overlap Wherein th is _overlap Is a preset distance threshold. If the condition is not met, continuing to traverse the next item mark line of the key frame until the condition is met or all target lines included in the key frame are completely traversed.

(4) Repeating the step (2) and the step (3) until all the target straight lines included in the common frame are fused with all the target straight lines included in the key frame.

(5) Repeating the steps (1) to (4) until all target straight lines included in all the common frames in the G are fused with all the target straight lines included in the key frames.

Step S307, according to the obtained straight line fusion result, inter-frame coding is carried out on the continuous multiple laser point cloud frames, and compression information of the continuous multiple laser point cloud frames is obtained.

After finishing straight line fusion of all target straight lines included in all common frames in the G and all target straight lines included in the key frames, each laser point cloud frame in the G can be further subjected to inter-frame coding:

(1) Key frame f _K All target straight lines included are recorded in G.

(2) Acquiring a normal frame f in G _t Traversing all of its projected keyframes f _K Target lines under the reference frame will not be in the collinear lookup Table Table _overlap The target straight line in (1) is recorded in G and is stored in a collinear lookup Table _overlap Key frame f for target straight line in (a) _K Corresponding purpose inThe straight line is marked instead.

(3) Modifying the normal frame f _t Is a compressed information of (1): and (3) removing the frame header H and the linear information of all target lines, traversing all the point cloud segments, and modifying the linear sequence numbers associated with the linear point cloud segments into the linear sequence numbers modified in the step (2), wherein the non-linear point cloud segments are not processed.

(4) Repeating the step (2) and the step (3) until all the common frames in the G are processed.

Inter-frame encoding is carried out on a plurality of continuous laser point cloud frames in the point cloud group G, and compression information of the plurality of continuous laser point cloud frames in the point cloud group G is obtained as follows:

G＝{l ₁ ,l ₂ ,…,l _q |{ξ ₁ ,f ₁ },…,{ξ _K ,f _K },…,{ξ _N ,f _N }}

wherein { l } ₁ ,l ₂ ,…,l _q All are keyframe references.

Step S308, determining whether all laser point cloud frames are completely compressed; if yes, go to step S309; if not, step S303 is performed.

Step S309, adding frame header information to the compressed information of all laser point cloud frames.

If all laser spots Yun Zhen have not been compressed, the steps S303 to S307 are repeated. If all laser points Yun Zhen have been compressed, frame header information H may be added to the compression information of all laser point cloud frames finally obtained, so as to obtain compression information of all laser points Yun Zhen PC as follows: pc= { h|g ₁ ,G ₂ ,…,G _N }。

Compared with the related art, the compression method of the laser point cloud can extract straight lines in a single laser point cloud frame, replace original laser scanning points with the straight lines, and greatly reduce point cloud segmentation information on the straight lines into only remaining segmentation starting laser scanning point serial numbers, ending laser scanning point serial numbers and straight line serial numbers by utilizing the equal-angle resolution scanning characteristics of the laser radar, so that efficient compression of the laser point cloud in the frame is achieved. Meanwhile, the compression method of the laser point cloud can also utilize the characteristic of high overlapping degree of the laser point clouds in continuous laser point cloud frames to divide a point cloud sequence, namely all the laser point cloud frames into point cloud groups with fixed frames, select key frames in the point cloud groups, project straight lines in common frames under a key frame reference system, and conduct straight line fusion, so that the number of the straight lines is further reduced, the compression efficiency in the time sense is improved, and the efficient compression of the laser point clouds between frames is realized.

After compressing the laser point cloud, correspondingly, the embodiment of the application further provides a decompression method of the laser point cloud, as shown in fig. 4, including the following steps:

step S401, obtaining compression information of a laser point cloud frame; the compression information includes first compression information corresponding to each target straight line and second compression information corresponding to each region.

The target straight line is determined in the laser point cloud frame by the compression end based on the position of the laser scanning point in the laser point cloud frame, and the area is obtained by dividing the target straight line.

Step S402, according to a point cloud serial number maximum value and a point cloud serial number minimum value of laser scanning points located on a target straight line and included in the first compressed information, determining a point cloud serial number of each laser scanning point on the target straight line, determining a scanning angle corresponding to the point cloud serial number of each laser scanning point located on the target straight line according to an association relationship between the point cloud serial number and the scanning angle of each laser scanning point, and determining the position of each laser scanning point located on the target straight line in a laser point cloud frame based on straight line information of the target straight line and the scanning angle of each laser scanning point.

Specifically, after determining the scanning angle corresponding to the point cloud serial number of each laser scanning point located on the target straight line, if the straight line information of the target straight line includes the straight line parameter and the straight line serial number, determining the position of each laser scanning point located on the target straight line in the laser point cloud frame based on the straight line parameter of the target straight line and the scanning angle of each laser scanning point.

If the straight line information of the target straight line comprises the straight line serial number, determining that the target straight line is a collinear straight line, determining straight line parameters of the non-collinear straight line according to the non-collinear straight line corresponding to the straight line serial number, and determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line parameters of the non-collinear straight line and the scanning angle of each laser scanning point. Wherein, the collineation condition is satisfied between the collineation line and the corresponding non-collineation line.

Step S403, determining a point cloud serial number of each laser scanning point in the area according to the point cloud serial number maximum value and the point cloud serial number minimum value of the laser scanning points in the area included in the second compressed information, determining a scanning angle corresponding to the point cloud serial number of each laser scanning point in the area according to the association relation, and determining a position of each laser scanning point in the area in the laser point cloud frame based on the determined scanning angle and the scanning distance of each laser scanning point included in the second compressed information.

In some embodiments, corresponding to the adding of the compressed information of the frame header information in the step S309, the decompression method of the laser point cloud provided in the embodiments of the present application may be implemented according to the procedure shown in fig. 5, as shown in fig. 5, including the following steps:

Step S501, obtaining compressed information of all laser point cloud frames, and reading frame header information from the compressed information.

The compressed laser point cloud sequences share the same frame header information, so that the frame header information is read only once and is H= { fid theta _min ,θ _max ,θ _inc ,r _min ,r _max }。

Step S502 reads compressed information of a plurality of consecutive laser point cloud frames reaching a set frame number threshold.

Reading compressed information g= { l of continuous multiple laser point cloud frames in point cloud group G ₁ ,l ₂ ,…,l _q |{ξ ₁ ,f ₁ },…,{ξ _K ,f _K },…,{ξ _N ,f _N }}。

Step S503 reads compressed information of a single laser point cloud frame among the continuous plurality of laser point cloud frames.

And reads the compressed information { ζ } of the single laser point cloud frame from the point cloud group G _t ,f _t }。

Step S504, according to the compressed information of the single laser point cloud frame, determining the position of each laser scanning point in the laser point cloud frame.

The process of determining the position of each laser scanning point in the laser point cloud frame from the compressed information of the single laser point cloud frame comprises the following steps:

(1) One point cloud segment s of a single laser point cloud frame is read.

(2) If the point cloud segment s is a nonlinear point cloud segment, i.e., s= { i, j|r _i ,r _i+1 ,…,r _j Directly calculating coordinates of each laser scanning point in the non-linear point cloud segment:

x _i ＝r _i ·cos(θ _min +(i-1)·θ _inc )

y _i ＝r _i ·sin(θ _min +(i-1)·θ _inc )

(3) If the point cloud segment s is a straight line point cloud segment, i.e., s= { i, j|lid _h }, wherein lid _h For the line number of the target line under the key frame reference system, the formula can be passed first Projecting the target straight line to the reference frame of the current laser point cloud frame, and then calculating the coordinates of each laser scanning point on the target straight line:

θ _i ＝θ _min +(i-1)·θ _inc

(4) Repeating the step (2) and the step (3) until all the point cloud segments in the single laser point cloud frame are decompressed.

Determining whether all the laser point cloud frames in the point cloud group G are completely decompressed, if the single laser point Yun Zhen in the point cloud group G is not completely decompressed, repeating the steps S503 and S504 until all the laser point cloud frames in the point cloud group G are completely decompressed, and determining whether all the point cloud groups G in the point cloud sequence PC are completely decompressed, and if all the point cloud groups G in the point cloud sequence PC are not completely decompressed, repeating the steps 502 to S504 until all the point cloud groups G in the point cloud sequence PC are completely decompressed.

Compared with the related art, the decompression method of the laser point cloud can determine to recover the laser scanning point from the original scanning distance or recover the laser scanning point from the straight line in the point cloud group according to the point cloud segmentation type, so that the decompression of the laser point cloud can be completed rapidly and efficiently.

The compression method of the laser point cloud shown in fig. 1 is based on the same inventive concept, and the embodiment of the application also provides a compression device of the laser point cloud. Because the device is a device corresponding to the compression method of the laser point cloud, and the principle of the device for solving the problem is similar to that of the method, the implementation of the device can be referred to the implementation of the method, and the repetition is omitted.

Fig. 6 shows a schematic structural diagram of a compression device for laser point cloud according to an embodiment of the present application, and as shown in fig. 6, the compression device for laser point cloud includes a straight line extraction unit 601 and an information compression unit 602.

The straight line extraction unit 601 is configured to determine a target straight line in a laser point cloud frame based on a position of a laser scanning point in the laser point cloud frame, where the number of laser scanning points on the target straight line is greater than a first set number threshold, and point cloud serial numbers of the laser scanning points on the target straight line are continuous, the point cloud serial numbers of the laser scanning points are set based on a scanning order, and laser scanning points on different target straight lines are different;

an information compression unit 602, configured to take first compression information corresponding to each target straight line and second compression information corresponding to each region as compression information of a laser point cloud frame, where the region is obtained based on division of the target straight lines, and the first compression information corresponding to the target straight line includes straight line information of the target straight line, a point cloud serial number maximum value and a point cloud serial number minimum value of a laser scanning point located on the target straight line; the second compressed information corresponding to the region comprises a scanning distance, a point cloud serial number maximum value and a point cloud serial number minimum value of each laser scanning point in the region; the scanning distance of the laser scanning point is the distance between the laser scanning point and the laser emitting device of the laser radar.

In an alternative embodiment, the straight line extraction unit 601 is further configured to:

dividing laser scanning points included in a laser point cloud frame into a plurality of point cloud sets, wherein each laser scanning point is positioned in one point cloud set, and the point cloud sets comprise laser scanning points with continuous sequence numbers;

determining a target straight line corresponding to the target point cloud set aiming at the target point cloud set with the number of any one included laser scanning point being larger than a second set number threshold, wherein the target straight line is a straight line with the minimum sum of distances between the target point cloud set and each laser scanning point included in the target point cloud set; or the target straight line is the straight line containing the most laser scanning points in the target point cloud set.

determining a fitting straight line in the point cloud set by a least square method according to the positions of the laser scanning points in the point cloud set, and determining target scanning points meeting the set distance condition according to the distances between each laser scanning point in the point cloud set and the fitting straight line;

In an alternative embodiment, the straight line information of the target straight line includes a straight line parameter and a straight line sequence number, and the straight line sequence number included in the straight line information of the target straight line is set based on the sequence of the collected laser point cloud frames; or (b)

wherein the collinear line of the target lines is determined by:

and taking a target straight line which meets the set collineation condition with at least one target straight line included in the key frame as a collineation straight line in each target straight line included in the normal frame, wherein the target straight line which meets the set collineation condition with the collineation straight line is a non-collineation straight line corresponding to the collineation straight line.

In an alternative embodiment, the information compression unit 602 is further configured to:

In an alternative embodiment, the threshold condition is that the first point-line distance is less than the second set threshold distance and the second point-line distance is less than the second set threshold distance;

the first point line distance is the distance between a laser scanning point corresponding to the maximum value of the point cloud serial numbers positioned on a target straight line included in the common frame and a key target straight line; the second wire distance is the distance between the laser scanning point corresponding to the minimum value of the point cloud serial number positioned on the target straight line included in the common frame and the key target straight line.

The decompression method of the laser point cloud shown in fig. 4 is based on the same inventive concept, and the embodiment of the application further provides a decompression device of the laser point cloud. Because the device is a device corresponding to the decompression method of the laser point cloud, and the principle of solving the problem of the device is similar to that of the method, the implementation of the device can be referred to the implementation of the method, and the repetition is omitted.

Fig. 7 shows a schematic structural diagram of a decompression device for laser point cloud according to an embodiment of the present application, and as shown in fig. 7, the decompression device for laser point cloud includes an information acquisition unit 701 and an information decompression unit 702.

The information acquisition unit 701 is configured to acquire compressed information of the laser point cloud frame; the compression information comprises first compression information corresponding to each target straight line and second compression information corresponding to each region; the target straight line is determined in the laser point cloud frame by the compression end based on the position of the laser scanning point in the laser point cloud frame; the region is obtained based on the target straight line division;

an information decompression unit 702, configured to determine, according to a point cloud serial number maximum value and a point cloud serial number minimum value of laser scanning points located on a target straight line and included in the first compressed information, a point cloud serial number of each laser scanning point on the target straight line, determine, according to an association relationship between the point cloud serial number of each laser scanning point and a scanning angle, a scanning angle corresponding to the point cloud serial number of each laser scanning point located on the target straight line, and determine, based on straight line information of the target straight line and the scanning angle of each laser scanning point, a position of each laser scanning point located on the target straight line in a laser point cloud frame; and

And determining the point cloud serial numbers of all the laser scanning points in the area according to the point cloud serial numbers of the laser scanning points in the area and the point cloud serial numbers of the laser scanning points in the area, determining the scanning angles corresponding to the point cloud serial numbers of all the laser scanning points in the area according to the association relation, and determining the positions of all the laser scanning points in the area in the laser point cloud frame based on the determined scanning angles and the scanning distances of all the laser scanning points included in the second compression information.

In an alternative embodiment, the information decompression unit 702 is specifically configured to:

if the straight line information of the target straight line comprises the straight line parameter and the straight line serial number, determining the position of each laser scanning point positioned on the target straight line in the laser point cloud frame based on the straight line parameter of the target straight line and the scanning angle of each laser scanning point;

if the straight line information of the target straight line comprises the straight line serial number, determining that the target straight line is a collinear straight line, determining straight line parameters of the non-collinear straight line according to the non-collinear straight line corresponding to the straight line serial number, and determining the position of each laser scanning point on the target straight line in the laser point cloud frame based on the straight line parameters of the non-collinear straight line and the scanning angle of each laser scanning point, wherein the collinear straight line and the corresponding non-collinear straight line meet the set collinearly condition.

The embodiment of the application also provides electronic equipment based on the same inventive concept as the embodiment of the method. The electronic device can be used for compressing or decompressing the laser point cloud. In one embodiment, the electronic device may be a server, a terminal device, or other electronic device. In this embodiment, the electronic device may be configured as shown in fig. 8, including a memory 801, a communication module 803, and one or more processors 802.

A memory 801 for storing a computer program for execution by the processor 802. The memory 801 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, a program required for running an instant communication function, and the like; the storage data area can store various instant messaging information, operation instruction sets and the like.

The memory 801 may be a volatile memory (RAM) such as a random-access memory (RAM); the memory 801 may also be a nonvolatile memory (non-volatile memory), such as a read-only memory, a flash memory (flash memory), a Hard Disk Drive (HDD) or a Solid State Drive (SSD), or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited thereto. The memory 801 may be a combination of the above memories.

The processor 802 may include one or more central processing units (central processing unit, CPU) or digital processing units, etc. And a processor 802, configured to implement the compression method or decompression method of the laser point cloud when calling the computer program stored in the memory 801.

The communication module 803 is used for communicating with a terminal device and other servers.

The specific connection medium between the memory 801, the communication module 803, and the processor 802 is not limited in the embodiments of the present application. The embodiment of the present disclosure is illustrated in fig. 8 by a bus 804 between a memory 801 and a processor 802, where the bus 804 is indicated by a thick line in fig. 8, and the connection between other components is merely illustrative and not limiting. The bus 804 may be classified as an address bus, a data bus, a control bus, or the like. For ease of illustration, only one thick line is shown in fig. 8, but not only one bus or one type of bus.

According to one aspect of the present application, there is provided a computer program product or computer program comprising computer instructions stored in a computer readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the compression method or decompression method of the laser point cloud in the above-described embodiment.

The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: an electrical connection having one or more wires, a portable disk, a hard disk, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application.

Claims

1. A method for compressing a laser point cloud, comprising:

2. The method of claim 1, wherein the determining a target straight line in the laser point cloud frame based on the location of the laser scanning point in the laser point cloud frame comprises:

3. The method of claim 2, wherein the dividing the laser scanning points comprised by the laser point cloud frame into a plurality of point cloud sets comprises:

4. The method of claim 1, wherein the line information of the target line includes a line parameter and a line number, and the line information of the target line includes a line number that is set based on a sequence of the acquired laser point cloud frames; or (b)

wherein the collinear line of the target lines is determined by:

5. The method of claim 4, wherein said setting, as the collinear line, a target line satisfying a set collinear condition with at least one target line included in the key frame, among the target lines included in the normal frame, comprises:

6. The method of claim 5, wherein the set threshold condition is that a first point-line distance is less than a second set threshold distance and the second point-line distance is less than a second set threshold distance;

7. The decompression method of the laser point cloud is characterized by comprising the following steps of:

8. The method of claim 7, wherein the determining the location of each laser scanning point located on the target straight line in the laser point cloud frame based on the straight line information of the target straight line and the scanning angle of each laser scanning point comprises:

9. A compression device for a laser point cloud, comprising:

10. A decompression device for a laser point cloud, comprising:

11. A computer-readable storage medium having a computer program stored therein, characterized in that: the computer program, when executed by a processor, implements the method of any of claims 1-8.

12. An electronic device comprising a memory and a processor, the memory having stored thereon a computer program executable on the processor, the computer program, when executed by the processor, implementing the method of any of claims 1-8.