readFrame

Read Hesai point cloud from file

Since R2022a

Syntax

ptCloud = readFrame(hesaiReader)

ptCloud = readFrame(hesaiReader,frameNumber)

ptCloud = readFrame(hesaiReader,frameTime)

ptCloud = readFrame(___,ReadMode=readMode)

Description

ptCloud = readFrame(hesaiReader) reads the next point cloud in sequence from the Hesai^® PCAP file and returns a pointCloud object.

ptCloud = readFrame(hesaiReader,frameNumber) reads the point cloud with the specified frame number from the file.

ptCloud = readFrame(hesaiReader,frameTime) reads the first point cloud recorded at or after the given frameTime.

ptCloud = readFrame(___,ReadMode=readMode) reads the points that belong to the specified return mode readMode.

Examples

Read Hesai PCAP Point Cloud Using Frame Number

Download a ZIP file containing a Hesai packet capture (PCAP) file and then unzip the file.

zipFile = matlab.internal.examples.downloadSupportFile("lidar","data/hesai_BusyRoad.zip");
saveFolder = fileparts(zipFile);
pcapFileName = [saveFolder filesep 'hesai_BusyRoad.pcap'];
if ~exist(pcapFileName,"file")
    unzip(zipFile,saveFolder);
end

Create a hesaiFileReader object.

hesaiReader = hesaiFileReader(pcapFileName,"Pandar128E3X");

Read the fifth frame of the Hesai PCAP point cloud data.

frameNumber = 5;
ptCloud = readFrame(hesaiReader,frameNumber);

Display the point cloud.

pcshow(ptCloud(1))

Read Hesai PCAP Point Cloud Using Time Duration

Download a ZIP file containing a Hesai packet capture (PCAP) file and then unzip the file.

zipFile = matlab.internal.examples.downloadSupportFile("lidar","data/hesai_BusyRoad.zip");
saveFolder = fileparts(zipFile);
pcapFileName = [saveFolder filesep 'hesai_BusyRoad.pcap'];
if ~exist(pcapFileName,"file")
    unzip(zipFile,saveFolder);
end

Create a hesaiFileReader object.

hesaiReader = hesaiFileReader(pcapFileName,"Pandar128E3X");

Read the first Hesai PCAP point cloud frame from 3 seconds after the StartTime.

frameTime = hesaiReader.StartTime + seconds(3);
ptCloud = readFrame(hesaiReader,frameTime);

Display the point cloud.

pcshow(ptCloud(1))

Input Arguments

hesaiReader — Hesai file reader

hesaiFileReader object

Hesai file reader, specified as a hesaiFileReader object.

frameNumber — Frame number of desired point cloud in file

positive integer

Frame number of the desired point cloud in the file, specified as a positive integer. Frame numbers are sequential.

frameTime — Frame time of desired point cloud in file

duration scalar

Frame time of the desired point cloud in the file, specified as a duration scalar in seconds. The function returns the first frame available at or after the specified frameTime.

readMode — Mode for reading data from Hesai PCAP file

"hesaiReader.ReturnMode" (default) | character vector | cell array of character vectors | string scalar | string array

Mode for reading data from the Hesai PCAP file, specified as a character vector, cell array of character vectors, string scalar, or a string array. This value must be a subset of the ReturnMode property of the hesaiFileReader object.

If you specify this argument as a cell array of character vectors or string array, then this function returns a point cloud array containing point clouds that belong to the specified modes in the same order.

Example: ReadMode="hesaiReader.ReturnMode" specifies the return mode to read point cloud data.

Output Arguments

ptCloud — Point cloud

pointCloud object | array of pointCloud objects

Point cloud, returned as a pointCloud object or array of pointCloud objects. The function returns an array of pointCloud objects only when you specify readMode as a cell array of character vectors or string array. The order of the pointCloud objects in the array corresponds to the order of the specified read modes in the readMode argument.

Version History

Introduced in R2022a