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<div class="gmail-cooked"><p>Hello,<br>
i’m taking the liberty to post a message in order to share an use case.<br>
Our need/purpose is to find existing methods/tools that would allow to
perform segmentations with the aim of helping botanists for pre-map
physiognomic units before to go on the field. In other words : to
produce a delineation (polygonal layer) of physiognomic units. In my
humble opinion, this is an unusual need/use case because the
segmentation is NOT intended/aimed as a first step before
classification. The goal is to reproduce as closely/faithfully as
possible the botanist’s photo-interpretation. We need to find the right
balance/parameters between the number of segments, their sizes, and
their compactness (shape). The idea would be to perform relevant
segmentation across the entire area being processed, neither
over-segmented nor under-segmented.<br>
With optimal parameters/configuration and input variables/data that can
vary depending on the environment (urban, agricultural, wooded,
herbaceous).</p>
<p>I’ve done some tests, notably via Qgis with OTB Approaches Region Merging:<br>
<a href="https://www.orfeo-toolbox.org/CookBook-7.0/Applications/app_GenericRegionMerging.html">https://www.orfeo-toolbox.org/CookBook-7.0/Applications/app_GenericRegionMerging.html</a><a href="/"></a><br>
I haven’t really tested other traditional approaches (such as cluster
mean shift or watershed, for example). Until now, I haven’t tested AI/DL
because I thought there wouldn’t be any segmentation models trained on
IRC ortho DB images that could meet our needs.<br>
This is why I prioritized “traditional” segmentation tools/approaches.</p>
<p>My tests were done using satellite spot6/7 images and Infrared Colour
aerial orthographic databases (franch mapping agency). Tests with the
aerial orthographic database are more resource-intensive and
time-consuming. Furthermore, this OTB tool tested (GRM) is not suitable
for large images. The results are quite good, particularly for
agricultural and urban areas.<br>
For forested areas, it’s more complicated. And in order to improve the
results, it may be necessary to consider integrating textures or
indicators (NDVI or other) ?</p>
<p>if you have any comments or suggestions for guidance regarding methods/tools/data, I would be happy to read you.</p>
<p>Thank you in advance.</p>
<p>Best regards,</p></div>
<br></div>