Supporting Imagery and Lidar in the ArcGIS platform has been around for a long time. In the ArcGIS Server Space, Image Server became available at 9.3.1. Since then it has evolved to Mosaic Datasets, Image Services, Raster Functions and now raster analytics. Now imagery is really an integral part of the ArcGIS platform. However, it is only as performant when the imagery is managed and configured optimally.
I often get asked,
- what format should I store my imagery in?,
- How many images can be in a Mosaic Dataset?
- How should I structure my imagery? and
- what is the maximum number of images per folder?
When answering these questions I have drawn on past experience and advice from Esri. Now though Esri have compiled all this information into an Excellent Centralised resource Imagery Workflows – Best Practices https://doc.arcgis.com/en/imagery/workflows/best-practices/what-are-best-practices.htm
In the Imagery formats and Performance section it details topics such as:
- File format suitability
- Recommended imagery formats
- Reformatting imagery
- Working with large mosaics
- Storage system performance
If you’re going to be managing imagery and lidar I recommend you reads these documents. They are comprehensive and invaluable. I must admit I have been doing this for 12 years now and there is information on Lidar management that I did not know about.
This is just one component of the ArcGIS Imagery Workflows documentation Esri has just produced.
ArcGIS supports LiDAR! It supports both XYZ and LAS files. It can read and display these formats as point clouds or surfaces, in both 3D and 2D. These can be viewed in ArcMap, ArcScene, ArcGIS Pro and as elevation services through ArcGIS for Server. But this is common knowledge right? ArcGIS has been able to do this since 9.3 and we all knew that right?
Well I thought this was the case. Often though it is not. Many people are today just starting to investigate the best tools for LiDAR exploitation not realising the capabilities of the ArcGIS Platform and the wealth of knowledge available to support their investigation. If you want a good place to start take a look at this web page What is LiDAR data?.
But let’s take a step back from the tools right now and ask yourself for what purpose do I want LiDAR data? Do I want it for flood modelling, DEM creation, building extraction or power line detection. Do I want to just differentiate between ground and non-ground or do I need it classified into buildings, trees, ground and water? The reasons for asking these questions is that the answers will dictate the order you place for LiDAR.
Imagery and remote sensing has always been one of my areas of interest in GIS. As a support analyst at Esri Australia I get a large number of imagery-related questions and I often help clients learn how to process their geospatial imagery and LiDAR data in ArcGIS.
Lidar (or Light Detection and Ranging) technology has become very popular and accessible in recent years. Because it provides high resolution elevation data, it’s now extensively used in the GIS world for mapping, spatial analysis and 3D visualization.
Although Lidar data can be used in many of the ArcGIS Desktop software, it turns out that many users are not aware of some basic workflows that can be utilized to extract raster Digital Elevation Models from their LAS point clouds in ArcGIS.
The question “how do I create a DEM from my Lidar data” is one of the most frequently asked questions when it comes to imagery related queries or support incidents. So I decided to prepare a quick overview of tools and methods that you can use to extract raster surfaces from your Lidar (*.las) files.
Below, I will outline the methods to extract the DEMs (Digital Elevation Model, also referred to as bare earth) and DSMs (Digital Surface Model, which is the first return surface which contains buildings, tree canopy etc.). Let’s get into it!!
The year 2014 has started with some seriously interesting news from Esri Inc. , and of special interest to ArcGIS Desktop users who use Lidar data in their day-to-day work.
On January 7, Esri released the new version of ArcGIS for Desktop – 10.2.1- and introduced a new image format call zLAS, which will be used to compress and optimize large collections of Lidar datasets, and which will be supported as a “direct-read” format in the new version of the software.
ArcGIS for Desktop v.10.2.1 is now available for the general public and you can login to the Customer Care Portal to download it. For those of you using ArcGIS 10.1 and 10.2 there is no need to uninstall your ArcGIS Desktop as v10.2.1 will be installed on top of your existing version.
In addition to the desktop release a new tool was released by the Imagery team which has been made available through the ArcGIS Resources website. This tool is called LAS optimizer and it can be downloaded for free here: http://www.arcgis.com/home/item.html?id=787794cdbd384261bc9bf99a860a374f
LAS Optimizer allows you to compress your LIDAR data (*.LAS), producing a set of *.zLAS files – an optimized version of the input Lidar datasets, which can be used for sharing, publishing and archiving. Continue reading
This morning I presented a session on LiDAR in ArcGIS. The focus of the session was storage, analysis and dissemination of LiDAR data.
I demonstrated just how LiDAR data can be QA checked by Using the Point Information tool, How LiDAR can be thinned using the LAS to Multipoint tool and how seamlessLiDAR data can be distributed to non GIS experts via ArcGIS Server Image Extension. Continue reading