Comment ça marche /how it works

INFERNO: a new software processing radar interferometry time series using Sentinel 1 products

=> The applications of interferometric techniques on radar images are currently developing in many fields. Being able to easily process and plot radar images, interferograms or time series of interferograms with a tool and data that are free and available without being a specialist is an important issue for scientists or companies that do not […]

01.09.2022

The plainbow over Fraser river sediment plume

Sentinel-2 captured an impressive view of the Fraser river sediment plume in Georgia Strait caused by the historic flood in British Columbia (250 mm rainfall in 48 hours). The image contains an amusing detail west off the Vancouver International Airport. This red-green-blue object is an airplane or « plainbow« . It is due to shifts between the […]

22.11.2021

Is DS 4 EO BS?

EO, RS, GS, DS, AI, ML, DL, BS, WTF? Everybody in the Geosciences (GS) and Remote Sensing (RS) community is now aware of the great advances in Data Science (DS) and Machine Learning (ML) that have taken place in the last 10 years. Although many people talk about Deep Learning (DL) or Artificial Intelligence (AI), […]

11.10.2021

Le Mask R-CNN pour la délinéation de parcelles : retour d’expérience

=> Les techniques de l’état de l’art en Deep Learning permettent-elles une délinéation individuelle de chaque parcelle de culture, comme le laisse penser cet article récent ? C’est ce que nous avons cherché à savoir au cours d’un stage au CESBIO en cherchant à qualifier l’architecture Mask R-CNN pour cette tâche. Nous vous livrons ici […]

24.09.2021

Feedback on Mask R-CNN for croplands delineation

=> Do state-of-the-art deep learning techniques allow for individual delineation of each cropland, as suggested by this recent article? In the context of an internship at CESBIO, we tried to evaluate the performance of Mask R-CNN architecture for this task. In this post, we summarize what we learned. Mask R-CNN principles To sum up, Mask […]

Can surface reflectance be negative ?

=> Here is a frequently asked question : I noticed, in such L2A product processed by MAJA, that some pixels had negative reflectances, is it normal ? No, it should not happen, but the fact it happens is not entirely surprising, I will explain it below. Unlike negative reflectances, reflectances greater than one can exist, […]

06.04.2021

Les réflectances de surface peuvent-elle être négatives ?

=> Voici une question que je reçois assez fréquemment : J’ai remarqué dans (tel produit L2A Sentinel-2 corrigé des effets atmosphériques par MAJA) des réflectances négatives ou égales à zéro. Est-ce normal ? Non, ce n’est pas normal, mais ce n’est pas totalement surprenant non plus. Contrairement aux réflectances négatives, qui ne devraient pas exister, […]

Upgrade of let-it-snow to compute the fractional snow cover

In preparation for the next Pan European high resolution snow and ice monitoring service, I have upgraded the let-it-snow (LIS) processor to enable the computation of the fractional snow cover (FSC) within the pixel. So far LIS was only used to compute a « binary snow mask » (in fact ternary: snow, no-snow, cloud). However, the EEA […]

12.09.2019

[Comment ça marche] Les réflectances peuvent-elles être supérieures à un ?

Attention, ce document contient des équations => A force d’écrire des articles sur ce blog, ou sur les réseaux sociaux, ou parce que je publie des codes sur github,  je reçois de nombreuses questions, auxquelles j’essaie de répondre. Une partie d’entre elles porte sur les valeurs des réflectances, comme par exemple: Le fait que les […]

04.09.2019

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