Version 1 (modified by mark1, 7 years ago) (diff)

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LiDAR Data Delivery Contents

This page describes the file formats and delivery structure used in the LiDAR data deliveries.

Delivery Structure

A standard delivery directory contains the following sub directories:

  • bin - Contains useful post-processing applications
    • pt_cloud_filter - Windows and Linux versions of software to remove classified points from ASCII files.
  • dem - Contains a Digital Elevation Model suitable for use with APL hyperspectral processing software.
  • doc - Contains a copy of the most recent data quality report.
  • flightlines - Contains the processed LiDAR point cloud data.
    • las1.0 - Contains LAS version 1.0 point data files.
    • las1.3 - Contains LAS version 1.3 point data and waveform data files.
    • ascii - Contains ASCII point data files.
  • logsheet - Contains a logsheet that gives a brief overview of the flown project
  • screenshots - Contains JPEG files of level-3 processed data including mosaics.

Digital Elevation Model

The format of the delivered Digital Elevation Model (DEM) is band Sequential (BSQ) ENVI format binary data. The projection is in WGS-84 latitude and longitude, with heights relative to the WGS-84 spheroid. There is an accompanying ASCII text header file containing the required information to read the binary data. In most cases, the LiDAR data will have been 'patched' with ASTER data. This will extend the coverage of the DEM which is often required for processing the hyperspectral data.

Screenshot images

The screenshots are supplied as JPEG images. This is a type of compressed image format that can be opened by most image viewers. The supplied screenshots include one of the DEM and one of the LiDAR intensity values. If the flight is in the UK and one where Ordnance Survey licensing allows, the intensity images will contain vector overlays to show the expected accuracy of the geocorrection.

Read-Me, Logsheet and Data quality report

The documents included with the delivery are in PDF. This is an open, platform independent standard for distribution of documentation, which allows graphical, text and tabular data to be included in the same file. Free viewers are available for displaying these documents.