How to select 4 dates for flood ?
Hello, I would like to know how do you automatically select 4 dates for flood when you train the model ?
I guess that date # 2 is given in pages like https://rapidmapping.emergency.copernicus.eu/EMSR745/download as "Event time (UTC)".
Date #1 is probably any date before the event, say, 2 weeks before.
But how do you select dates #3 and #4 ? Should #3 be selected after the flood/fire was finihed or not ?
How do you get this date automatically ?
The related question: If Sentinel2 image is missing for the date due to clouds, you need to chose another date. In this case do you need to adjust the date for Sentinel1 ?
Hi @VadimEngelson , we selected the dates based on this rule:
#1: 60-30 days before the event, tile with fewest clouds
#2: 30-3 days before the event, tile with fewest clouds
#3: closest tile to the event annotation
#4: 7+ days after the event
More details are shared in the upcoming technical report. We are still finalizing this one.
The model is trained with some cloudy S2 images + S1 as well as with some missing images. But an S2 image without clouds naturally performs better