readers.copc

The COPC Reader supports reading from COPC format files. A COPC file is a LASzip (compressed LAS) file that organizes its data spatially, allowing for incremental loading and spatial filtering.

Note

LAS stores X, Y and Z dimensions as scaled integers. Users converting an input LAS file to an output LAS file will frequently want to use the same scale factors and offsets in the output file as existed in the input file in order to maintain the precision of the data. Use the forward option of writers.las to facilitate transfer of header information from source COPC files to destination LAS/LAZ files.

Note

COPC files can contain datatypes that are actually arrays rather than individual dimensions. Since PDAL doesn’t support these datatypes, it must map them into datatypes it supports. This is done by appending the array index to the name of the datatype. For example, datatypes 11 - 20 are two dimensional array types and if a field had the name Foo for datatype 11, PDAL would create the dimensions Foo0 and Foo1 to hold the values associated with LAS field Foo. Similarly, datatypes 21 - 30 are three dimensional arrays and a field of type 21 with the name Bar would cause PDAL to create dimensions Bar0, Bar1 and Bar2. See the information on the extra bytes VLR in the LAS Specification for more information on the extra bytes VLR and array datatypes.

Warning

COPC files that use the extra bytes VLR and datatype 0 will be accepted, but the data associated with a dimension of datatype 0 will be ignored (no PDAL dimension will be created).

Default Embedded Stage

This stage is enabled by default

Streamable Stage

This stage supports streaming operations

Example

[
    {
        "type":"readers.copc",
        "filename":"inputfile.copc.laz"
    },
    {
        "type":"writers.text",
        "filename":"outputfile.txt"
    }
]

Options

filename: COPC file to read. Remote file specifications (http, AWS, Google, Azure, Dropbox) are supported. [Required]

count: Maximum number of points to read. [Default: unlimited]
override_srs: Spatial reference to apply to the data. Overrides any SRS in the input itself. Can be specified as a WKT, proj.4 or EPSG string. Can’t use with ‘default_srs’. [Default: none]
default_srs: Spatial reference to apply to the data if the input does not specify one. Can be specified as a WKT, proj.4 or EPSG string. Can’t use with ‘override_srs’. [Default: none]

bounds

The extent of the data to select in 2 or 3 dimensions, expressed as a string, e.g.: ([xmin, xmax], [ymin, ymax], [zmin, zmax]). If omitted, the entire dataset will be selected. The bounds specification can be followed by a slash (‘/’) and a spatial reference specification to apply to the bounds specification.

polygon

A clipping polygon, expressed in a well-known text string, e.g.: POLYGON((0 0, 5000 10000, 10000 0, 0 0)). This option can be specified more than once. Multiple polygons will will be treated as a single multipolygon. The polygon specification can be followed by a slash (‘/’) and a spatial reference specification to apply to the polygon.

ogr

A JSON object representing an OGR query to fetch polygons to use for filtering. The polygons fetched from the query are treated exactly like those specified in the polygon option. The JSON object is specified as follows:

{
    "drivers": "OGR drivers to use",
    "openoptions": "Options to pass to the OGR open function [optional]",
    "layer": "OGR layer from which to fetch polygons [optional]",
    "sql": "SQL query to use to filter the polygons in the layer [optional]",
    "options":
    {
        "geometry", "WKT or GeoJSON geomtry used to filter query [optional]"
    }
}

requests

The number of worker threads processing data. The optimal number depends on your system and your network connection, but more is not necessarily better. A reasonably fast network connection can often fetch data faster than it can be processed, leading to memory consumption and slower performance. [Default: 15]

resolution

Limit the pyramid levels of data to fetch based on the expected resolution of the data. Units match that of the data. [Default: no resolution limit]

header

HTTP headers to forward for remote endpoints. Specify as a JSON object of key/value string pairs.

query

HTTP query parameters to forward for remote endpoints. Specify as a JSON object of key/value string pairs.

las

Read LAS VLRs and import as metadata. [Default: false]

keep_alive

The number of chunks to keep active in memory while reading [Default: 10]

fix_dims

Make invalid dimension names valid by converting disallowed characters to ‘_’. Only applies to names specified in an extra-bytes VLR. [Default: true]

srs_consume_preference

Preference order to read SRS VLRs. [Default: ‘wkt1, wkt2, projjson’]

nosrs

Don’t read the SRS VLRs. The data will not be assigned an SRS. This option is for use only in special cases where processing the SRS could cause performance issues. [Default: false]