Essayer d'utiliser l'imagerie Multiband pour identifier les surfaces perméables

Question

Bonjour, j'utilise ce tutoriel https://learn.arcgis.com/en/projects/calculate-impervious-surfaces-from-spectral-imagery/ pour trouver des surfaces perméables pour une possible plantation d'arbres dans notre ville. À l'étape Classify the imagery Étape 3 Cliquez sur Run, le processus dure quelques heures, environ 20 ou plus, ce qui est attendu compte tenu de la taille de la zone. Il génère des erreurs comme " ERROR 003436: No training samples found for these classes: Roof(Black Grey), ImperviousShadow, ArtificialTurf, Crop. Failed to execute (TrainSupportVectorMachineClassifier). Failed at February 24, 2022 1:25:05 PM (Elapsed Time: 48 minutes 34 seconds)", mais j'ai bien montré qu'il y avait des terres cultivées dans l'échantillon et je l'ai sauvegardé.<\/P> La deuxième exécution a généré " ERROR 003436: No training samples found for these classes: Roof(Black Grey), ImperviousShadow, ArtificialTurf, Crop. Failed to execute (TrainSupportVectorMachineClassifier). Failed at February 25, 2022 6:01:58 PM (Elapsed Time: 47 minutes 33 seconds)", encore une fois j'ai montré les ombres. <\/P> Quand j'ai finalement réussi à le faire fonctionner et à produire des résultats, ils étaient très inexactes ; identifiant par exemple l'eau ouverte comme des terres cultivées. J'ai suivi les instructions donc je ne suis pas sûr du problème ; est-ce que c'est parce que j'essaie de traiter une grande série d'images ?<\/P> <\/P>

IvanPotic · Answer

I had the same problem with the "ERROR 003436".

I want to confirm that @Taren_Esri first suggestion solved my problem.

I clipped the satellite imagery twice. First clip was wider area of Interest and second clip was the "area of interest", significantly smaller part. I was trying to classify smaller clipped part ignoring the fact that I noticed that when zooming to layer I have some invisible buffer (no data or some other problem that arose during clipping). Reverting the classification process to the wide clipped footage saved the day and the new classification process went smoothly. I used previously collected training samples from correctly formatted shape file.

Taren_Esri · Answer

For the sake of future reference, I recently worked on a case that resolved this same issue. If you encounter this error message, check two things. The first is that you are running your analysis on the same and original raster you trained your classes on. This means it can't have been clipped, masked, etc.  The second is ensuring your input training sample feature class is actually split and individual features that are appropriately labeled for their class. This means no multipart features. You can run Multipart to Singlepart to split them up if needed. Hope this helps someone!

dvandommelen · Answer

I've received this same error. Anyone know an answer?