read

Read data and metadata from blockedPointCloudDatastore

Since R2022a

Syntax

b = read(bpcds)

[b,info] = read(bpcds)

Description

b = read(bpcds) returns the data extracted from the blockedPointCloudDatastore object bpcds.

[b,info] = read(bpcds) also returns info, a structure containing information about where in the blockedPointCloudDatastore the data is extracted from.

Examples

Read Data and Metadata from blockedPointCloudDatastore

Create a blocked point cloud.

pcfile = fullfile(toolboxdir("lidar"),"lidardata", ...
                       "las","aerialLidarData.laz");
bpc = blockedPointCloud(pcfile,[300 300]);

Create a blockedPointCloudDatastore from the blocked point cloud.

bpcds = blockedPointCloudDatastore(bpc);

Read data and metadata from the blockedPointCloudDatastore. Display the metadata.

while hasdata(bpcds)
      [data,info] = read(bpcds);
      disp(info)
end

                ROI: [4.2975e+05 4.3005e+05 3.6798e+06 3.6801e+06 72.7900 125.8200]
           BlockSub: [1 1 1]
           PCNumber: 1
    PointAttributes: [1x1 lidarPointAttributes]
          BlockSize: [300 300 53.0300]

                ROI: [4.3005e+05 4.3035e+05 3.6798e+06 3.6801e+06 72.7900 125.8200]
           BlockSub: [2 1 1]
           PCNumber: 1
    PointAttributes: [1x1 lidarPointAttributes]
          BlockSize: [300 300 53.0300]

Input Arguments

bpcds — Blocked point cloud datastore

blockedPointCloudDatastore object

Blocked point cloud datastore, specified as a blockedPointCloudDatastore object.

Output Arguments

b — Data from blockedPointCloudDatastore

cell array

Data from the blockedPointCloudDatastore, returned as a cell array of block data. The length of the cell array is equal to the value of the ReadSize property of the blockedPointCloudDatastore object.

info — Metadata from blockedPointCloudDatastore

structure

Metadata from the blockedPointCloudDatastore, returned as a structure with these fields. If the value of the ReadSize property of the blockedPointCloudDatastore object is greater than 1, these fields are arrays.

Field	Description
ROI	ROI of the block, specified as a six-element numeric row vector in the order [xmin xmax ymin ymax zmin zmax].
BlockSub (since R2024b)	Block subscripts of the current block.
PCNumber	Index into the bpcds.PointClouds array corresponding to the blockedPointCloud from which this block is read.
PointAttributes	Attributes for each point, specified as a lidarPointAttributes object.
BlockSize	Value of the BlockSize parameter.

Version History

Introduced in R2022a

R2024b: Read subscripts of current block

The function returns the subscripts of the current block in the info output argument.