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Chapter in QGIS and Applications in Agriculture and Forest book

I’m glad to share with you my first publication of a chapter with Pauline Perbet.

According to Nicolas Bagdhadi who edited with Clément Mallet and Mehrez Zribi theses new series of books  “QGIS in remote sensing”, these 4 volumes “aim to facilitate the appropriation and operational use of the Quantum Geographic Information System (QGIS) software in the field of remote sensing”.

Volume 1 : QGIS and generic tools / QGIS et outils génériques (QGIS, GDAL, GRASS, SAGA, OTB)
Volume 2 : QGIS and applications in agriculture and forest / QGIS et applications en agriculture et en foresterie
Volume 3 : QGIS and applications in territorial planning / QGIS et applications en aménagement du territoire
Volume 4 : QGIS and applications in water and risks / QGIS et applications en eau et risques

This work is carried out by scientists who are proficient to a high level of technicality. The book is targeted at students (Masters, engineering students, PhDs), engineers and researchers who have already adopted geographic information systems.

My chapter is number 7 in volume 2, “Remote Sensing of Distinctive Vegetation in Guiana Amazonian Park” , and of course it uses dzetsaka plugin :

The Guiana Amazonian Park has satellite imagery available all over its territory. The SPOT-5 sensor offers 10 m imagery resolution that allows for the detection of distinctive vegetation, distinguished from the tropical forest and remote sensing was used to detect those distinct sets of vegetations. SPOT-5 satellite imagery was acquired from the SEAS Guiana project. SEAS offers free French Guiana SPOT-5 archive images to the public organization located in this territory. Procedure and tool location can slightly differ according to the operating system or the quantum geographic information system (QGIS) version used. This chapter discusses the use of Windows 10, QGIS 2.14.14, Grass 6.4.3 and OTB 5.0.0. The dzetsaka plugin was designed to classify images directly from QGIS. To unlock all its capabilities, several dependencies should be installed first to use all the famous classification algorithms like random forest (RF) and support vector machine (SVM). For Windows installation, it is better to use OsGeo.

In addition to the text, readers will have access to data and tools allowing the integral realization of the scientific procedures described in each chapter, as well as screenshots of all the windows which illustrate the manipulations necessary for the realization of each application.

ISBN : 9781786301888

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HTML and CSS lego icons have a new friend : Javascript !

I was building my new courses in web development for Master SIGMA when I found some really nice illustrations explaining the role of HTML and CSS. But something was missing : Javascript ! I don’t manage to find the original author of these lego icons, but if you do, please comment.

Now, here’s the javascript animated lego icon :

Feel free to use it 🙂 If you need to mention someone : Nicolas Karasiak.

Sources are available on GitHub

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Get ROI values from raster and combine all CSV (remote sensing statistics with R)

R is a great tool for statistics, even if it may be slow in calculing raster’stats, it is really a good way for batching all of your work and presenting your data using MarkDown language. This example is one of my first autonomous script in R, and it is very exciting for further. You can download the whole script SPOT5-GetROIvalues.R on GitHub.

Before showing you the different steps of the code, I need to present you the way I structured my data, because the script is going to parse them and to compile all tables in one file.

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dzetsaka : how to make your first classification in Qgis ?

I just published the plugin dzetsaka : classification tool (github/qgis) on Qgis plugin server. This is a very simple plugin to make a fast but powerful classification. I used it for making numerous classifications of SPOT 5 scenes in the French Guiana Amazon forest.

A project with samples (an old map (map.tif) and ROI (train.shp)) is available on the docs branch. You can download these files directly here.

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How to get rid of “unknown enum QgsMapLayerProxyModel::PluginLayer” in Qgis ?

I was developping a plugin in Qgis with the Combobox layer (QgsMapLayerComboBox) which allows you to show all opened layer in Qgis. It’s a great tool that allows the user to select a raster or a vector easily.
On Ubuntu everything works perfectly, but when I was trying on Windows I always had this error when loading the plugin “error enum : QgsMapLayer”. Read More

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Making a modern map with an old style

A project with my teacher Laurent Jégou was to design a recent map with an old map style. Some students chose to make the opposite, making an old map looks like a recent one (for example Rome in 300 A.D with an Open Street Map style).
I took the first project and I worked to make an actual map of Toulouse with an old style. I got most of my inspiration with the Rome map available on geotests (16mo).

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How to split a gpx ? In each track, segment or trkpt ? (Python)

I had a project in my master’s degree (Sigma) to use python for doing something with a GPX file. There was a project like finding summit or pass, but I choose to edit a GPX to split it into in each of his tracks, segments, or by cutting the file into a specific point.

I choose to use LXML library to parse and edit .gpx, and OS to batch the process with multiple .gpx.

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