combining 3d imagery and lidar with arcgis in aerial and mobile applications

Combining 3D Imagery and Lidar with ArcGIS in aerial and mobile

applications

Aldo Facchin – Geosoft Srl (Italy)

www.geosoft.it

Geosoft Srl - Italy

Who we are ?

�An italian company focused on software products for …

• Map production

• 3D photogrammetry

• LiDAR

• Mobile Imaging & Laser Scanning (from vehicle)

�Founded in 1992

�Main markets (last 3 years) :

• 70-85 % Map, Survey and Engineering industry

• 15-30 % Public Administration, University and Research

Geosoft Srl - Italy

Our offer…

A family of ArcGIS Desktop stereoscopic extensions for :� Aerial photogrammetry and lidar (with a patented method)

� Terrestrial Laser Scanning

� Mobile Laser Scanning

Aerial Stereo Imagery and LidarArcGDS Stereo + LiDAR extension

Aerial Stereo Imagery and Lidar3D Imagery and Lidar are better if combined

Geodatabase updating using orthophotos :

� Well known datatype� Large diffusion

Poor photointerpretationDifficult to collect XY positionImpossible to collect HEIGHT / Z valuesImpossible to collect HEIGHT / Z valuesYour world is flat

WeWe needneed a 3D systema 3D system


GIS is a “decision support system”

Which kind of decisions you can take if your data aren’t enough accurate ?

Please take care about accuracy...


If the ortophoto exists, also the overlapped images exist...

“Imagery” is the cheapest dataset already ready for 3D

3D Imagery is part of the “photogrammetry”

workflows and products

LiDARis the emerging technology

naturally “born for 3D “


Photogrammetry (3D imagery) alone is not enough…

� Optimal photointerpretation (image data is continuous)

� Use of RGB, CIR images with 8+ bit per channelchannel

� Already experienced operators, well known procedures and systemNew digital cameras have bad B/H ratio so Z quality is poorData quality is not constant (Z in particular) because depends on the operator (stereoscopic perception)Image correlation often have problems exactly where we need (for ex. roof edges)


LiDAR alone is not enough…

� Optimal precision (especially Z) respect to the photogrammetry at the same flight height

� Possibility to classify the points cloud� Data quality is constant (Z in particular) � Data quality is constant (Z in particular)

because does not depend on the operator (snap)

� Data have low costs and short acquisition timesInterpretation is very poor because the data are discretePoint density impacts a lot on costThe points don’t have directly the color of the objectsXY precision is poorer than Z


The solution :


The solution :

� The operator move the cursorobserving the imagery stereo scene

� The software update the cursor height according with the point cloud,height according with the point cloud,using different alghoritms

� Stereo imagery are used for XY andphotointerpretation

� LiDAR point clouds are used for updating collimation mark height (Z)

� The point cloud is better than using DSM or other resampled products

� The operator has only the “check” the collimation mark height (Z), not directly and carefully positio n it !


� We requested to register a patent for the industrial process of producing maps using 3D imagery and lidar...

� The European Patent Office approved it !!!

� The patent will be extended in Europe, USA, Canada, Brasil, India, etc.

Live demoArcGDS Stereo + LiDAR extension


Characteristics of ArcGDS LiDAR method (patent pending)

It’s a tool for the production of high quality 3D geodatabases.� Photointerpretation is available (photos, 3D...not orthophoto) � LiDAR acquisition allow much better Z precisions than photo-

mapping or orthophoto digitalizationmapping or orthophoto digitalization� Mapping (for ex. streets or buildings) is coherent with LiDAR� Operator checks Z during mapping and eventually changes it

manually� Is for everybody because not require a high photogrammetric

experience� Snap uses cloud classification � Transversal profile view helps operator for a better interpretation


Key concepts :

� Stereoscopy is available for all the users at low cost, inside ArcMap, for images and point clouds

� The time of proprietary CAD platform for maps data capture is over !� The time of proprietary CAD platform for maps data capture is over !

� Combine stereo images and LiDAR point clouds to obtain the best accuracy and efficiency

� It’s the ideal tool for QC/QA after automatic featu re extraction phase

� Can be bundled with raw data (images & point cloud) by data providers

� With this (patented) method…• medium format cameras can be used• low density point clouds can be used

Mobile Laser Scanning and ImageryArcGDS for MLS

Mobile Laser ScanningUse video to quickly navigate and 3D stereoscopic v ision accurate data collection

Now…

� The current trend on MLS is to do all the work using laser scanner(s) point cloudusing laser scanner(s) point cloud

� The camera(s) are only for give color to point cloud

� Do you think to handle a mobile laser scanning road network project with a CAD ?


With the “Point cloud only” approach you need high density point cloud…

� More scanners� More scanners� Lower speed in mission� Huge files to manage

Impact on :� system cost� mission productivity� post processing productivity


Our idea…

� Try to use camera image sequences (video) to quickly navigate…quickly navigate…

� Use the point cloud only for the 3D precise measure task

� Use the images to recognize the objects you have to collect

� Use 3D glasses to save time

Mobile Laser ScanningUse 3D glasses to save time, use images and point c louds as they are

The interface :

Mobile Laser ScanningUse 3D glasses to save time, use images and point c louds as they are

The solution :

� You can open the video window and the 3D laser window from any point in the ArcMap dataframe

� You can use normal ArcMap tools pointing in the video window or on the 3D laser window

� The 3D laser window can be viewed stereoscopically using 3D glasses

� With 3D glasses you see immediately if are picking the right point

More More productivityproductivity, , lessless mistakesmistakes

Conclusion

� Images don’t replace point clouds and vice-versa� Use the best of each data type� Combine them� GIS is necessary for a good data collection

• for data consistency• for data consistency• for multiuser handling• for versioning• for integration with other sources (ex. ArcGIS

Online)• etc.

� There are no more advantages on using CAD for 3D

Thank you !

Gracias!

Grazie !

[email protected]

For further information, please visit Geosoft at booth # 6.

combining 3d imagery and lidar with arcgis in aerial and mobile applications

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