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Posts Tagged ‘3d geovisualization’

La geográfica cabecera de ‘Up in the air’ con George Clooney

2015/08/24

Para alguien que maneja mapas a diario es una sorpresa interesante cruzarse con esta cabecera de la película de Jason Reirman protagonizada por George Clooney ‘Up in the air’. Nubes, campos de cultivo, ciudades en 2D, 3D. Qué bien he elegido mi profesión:-)

Para alguien que viaja mucho, salvando las distancias, este vídeo, también del mismo fil ‘Up in the air’ es un simpático recuerdo de lo que es un viaje pasando por uno y mil auropuertos, arcos voltaicos, empaquetando, desempaquetando…

Espero que os guste!

Alberto

(Fuente: Jose Ignacio Sánchez de Nosolosig)

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Remote Sensing, Photogrammetry, Lidar and Landuse IGN Spain

2014/11/18

teledeteccion-fotogrametria-lidar-usos-del-suelo-ign-20141118b

A few more lines for leting you know again that i passed this other course just now in Instituto Geográfico of Spain (IGN).

Remote Sensing, Photogrammetry, Lidar and Landuse, a comprehensive 40h update on relevant information i need tu use on a daily basis. This ‘update’ helps me to better understand what i am working with and this way, being able to properly describe it for my daily analysis,

DTM from SRTM? Let’s compare sources using RMSE (Root Mean Square Error) and a gaussian kernell density map

2014/10/29

I guess we all can make a DTM out of many sources but SRTM is one of the most common ones, right?. Then let’s learn from this very simple approach how close we are from the SRTM raw data.

  1. Selecting a not very big representative area to be able to handle it,
  2. exporting raster to polygon (from SRTM 3 arcsec/90m) dataset 1
  3. exporting raster to polygon 30m (our DTM dataset) dataset 2
  4. exporting to POIs 30m (our DTM dataset) dataset 2b
  5. Spatial join POIs dataset 2b vs dataset 1
  6. RMSE
  7. visualizing delta using a density map/gaussian kernell +appropriate symbolization

In yellow we see theres a full correspondence between SRTM and our DTM dataset and in blue there’s a ‘hole’ and in red there’s a ‘mountain’, this means it’s in here where the shift is more important.

This way we can highlight if sources are OK.

It’s simple but it works. How do you like it?. Please feel free to send some feedbak.
(Software used: ArcGIS 10.1, Global Mapper 13.2)

Cheers,
Alberto Concejal
MSc GIS, QC

DENSITY-MAP-V1-VS-SRTM-20141021

density maps parameters

rmse-sierra-leone-20141008-02

Spatial join between both DTM datasets

blog-20141029

Density map for highlighting differences between both datasets (ours and SRTM’s)

blog-20141029-03

RMSE. It’s not too big so there’s need to visualize to find potential bizarre spots

blog-20141029-02

bizarre DTM heights

Solar + Shadows analysis on Rue Massillon, Nantes (France)

2013/04/04

This is the beautiful building in from of my house in Nantes… Let’s model it first using Sketchup. Also i have used a non standard style only for visualization purposes…

rue_massillon_02

If we have the North behind us this means we are going to have a lot of light… but so far we are just guessing…

rue_massillon_01

Now we know if for sure. Take a look at the results by M. Capeluto’s Solar Analysis.

rue_massillon_03

If we face South we notice there’s a lot of sun in the other side of the building (every line is a summarized path during a month, being the higher the closer to the summer solstice)

Please take a look at the video prepared by Tomasz Janiak, the developer of the tool.

Hope you guys find it interesting. Please let me know your thoughts.

Alberto

Visualizing LAS LIDAR data with sketch-up

2010/07/02

While trying to figure out the way to get a 3D model from raw Lidar data, I first opened my LAS file in Global Mapper, exported it to DXF, imported then into Sketch-up and after recording a few scenes, I saved the animation… this is it!.

Alberto

Using Excel to calculate the RMSE for LiDAR vertical ground control points

2010/06/30

(source: http://dominoc925.blogspot.com/)

The height accuracy of the collected LiDAR data can be verified by comparing with independently surveyed ground control points on hard, flat, open surfaces. It is essentially just calculating the height differences for all the control points and then determining the height root mean squared error (RMSE) or differences. Most LiDAR processing software have the reporting function built-in. However, plain Microsoft Excel can also do the job (except for extracting the elevation from the LiDAR data).

Assuming that you are able to calculate the height differences for all the control points and place in a spreadsheet as shown in the figure below. I have a column of delta Z values in column A.

Then to calculate the RMS value for the elevation differences, I can do the following.

  1. In a cell, type in the formula:= SQRT(SUMSQ(A2:A18)/COUNTA(A2:A18))where A2:A18 are the values from cell A2 to A18 in the spreadsheet. Simply replace these with the actual locations on your spreadsheet.
  2. Press RETURN.
    The RMSE value is calculated.

(source: http://dominoc925.blogspot.com/)

Data acquisition: How do I know if this river is been well acquired?

2010/06/14

I’ve already entered my river but my imagery was in 2D so… was it well acquired?…  First of all, I import my shape (shp) file into Global Mapper (what a great sofware!) and export my vector file as a KML.

Import my river.kml file into my brand new Google Earth 5.2 or just double-click it in his location… easyest impossible!.

Select it and use ‘show elevation profile’,  a very useful new tool for these purposes…

And that’s it, constant altitude, almost perfect!.

Hope you have considered it interesting:-)

Alberto

The SketchUp 3D API: Working with 3D geospatial data

2010/06/14

I hereby post this video by Matt Lowrie (Google). hope it’s interesting for you guys.

Alberto

GIS+Architectural scenaries. Awesome!

2010/06/12

Even from scratch or from dgn/dxf vectorial format’s contour lines you create your own scenario.

Then import your model previously created using Sketch-up (this time i used google’s 3d warehouse, thank you Dilbert).

Stamp your house using sketch-up sandbox tools.

Then fur your scenario as if it was grass…

A little of photoshop like clouds and thats it!

Alberto Concejal
geographer, 3d designer & 3D GIS technician
albertoconcejal [at] gmail.com

Map24.com; My favorite route planner!

2010/06/03

My very good friend Fernando (a spanish/english like friend of mine:-)) introduced me this magnificent route planner he was using at that moment (three years ago!!!!)… map24.com had a very interesting 3D engine, very easy to use and very reliable… I’ve been using it since but it has never been one of the most famous among route planners in the market…

I strongly recommend it and i really like it a lot! enjoy!

http://www.es.map24.com/
http://www.map24.com/

Alberto Concejal
geographer, 3d designer & 3D GIS technician
albertoconcejal [at] gmail.com