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I'm trying to find a way to automatically download satellite imagery to create a database. I'm figuring this out and started with sentinelsat API, there isn't much about it out there due to its specificity. My steps where: I used this site https://geojson.io in order to select a polygon, and download a geojson file. I added that to a geodataframe (geopandas) apparently for no reason whatsoever actually. Followingly I used the polygon to add it to the query (api.query), got the products, looped through them, checked if they were online and tried downloading them, but I get the following error (for all of the online ones):

0  POLYGON ((-53.27854 -24.97081, -53.30223 -24.9...
Querying products: 100%|█████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 362/362 [00:06<00:00, 42.74product/s]
                                                                                  title  ...                                           geometry
f8184c3e-6760-461c-af2b-5cb3183f864d  S2A_MSIL2A_20211126T134211_N0301_R124_T22JBT_2...  ...  MULTIPOLYGON (((-52.89090 -25.39290, -52.87585...
f2a70ef8-b6ba-4612-8f3a-b4ec4d60ebc3  S2A_MSIL2A_20211126T134211_N0301_R124_T21JZN_2...  ...  MULTIPOLYGON (((-54.01898 -25.37484, -52.92975...
47d725db-7753-4407-9d67-90ec12053fac  S2B_MSIL2A_20211121T134209_N0301_R124_T21JZN_2...  ...  MULTIPOLYGON (((-54.01898 -25.37484, -52.92975...
b3a96909-c276-498e-ad77-4fc89675fa19  S2B_MSIL2A_20211121T134209_N0301_R124_T22JBT_2...  ...  MULTIPOLYGON (((-52.89090 -25.39290, -52.87585...
6ddcee95-edc5-4a33-b5a3-820dbbee3431  S2A_MSIL2A_20211116T134211_N0301_R124_T22JBT_2...  ...  MULTIPOLYGON (((-52.89090 -25.39290, -52.87585...
...                                                                                 ...  ...                                                ...
b5b00501-8c99-4a89-87c1-dc99c421cbd7  S2B_MSIL2A_20190615T134219_N0212_R124_T21JZN_2...  ...  MULTIPOLYGON (((-54.01898 -25.37484, -52.92975...
1cb316a6-025a-40e6-a051-6b3eb13a91d4  S2A_MSIL2A_20190610T134211_N0212_R124_T22JBT_2...  ...  MULTIPOLYGON (((-52.89090 -25.39290, -52.87585...
3b6181b8-459c-4a04-aa9e-ad8e1329a5e3  S2A_MSIL2A_20190610T134211_N0212_R124_T21JZN_2...  ...  MULTIPOLYGON (((-54.01898 -25.37484, -52.92975...
f8dddff3-e1da-4d7c-ae85-aa8aced8e337  S2B_MSIL2A_20190605T134219_N0212_R124_T21JZN_2...  ...  MULTIPOLYGON (((-54.01898 -25.37484, -52.92975...
d75470e8-bd80-42d0-9129-41db94aa292f  S2B_MSIL2A_20190605T134219_N0212_R124_T22JBT_2...  ...  MULTIPOLYGON (((-52.89090 -25.39290, -52.87585...

[362 rows x 41 columns]
Product ' 0 '
Product ' 1 '
Product: f2a70ef8-b6ba-4612-8f3a-b4ec4d60ebc3  is online.
Downloading S2A_MSIL2A_20211126T134211_N0301_R124_T21JZN_20211126T160417.zip:   0%|                                                                                                                 | 0.00/1.19G [00:00<?, ?B/s]
Traceback (most recent call last):
  File "c:\Users\phzoz\PythonProjects\Sentinel\main.py", line 32, in <module>
    api.download(product, directory_path="Data", checksum=True)
  File "C:\Users\phzoz\anaconda3\envs\sentinel\lib\site-packages\sentinelsat\sentinel.py", line 590, in download
    return downloader.download(id, directory_path)
  File "C:\Users\phzoz\anaconda3\envs\sentinel\lib\site-packages\sentinelsat\download.py", line 150, in download
    self._download_common(product_info, path, stop_event)
  File "C:\Users\phzoz\anaconda3\envs\sentinel\lib\site-packages\sentinelsat\download.py", line 229, in _download_common
    raise InvalidChecksumError("File corrupt: checksums do not match")
sentinelsat.exceptions.InvalidChecksumError: File corrupt: checksums do not match

Here's the code summary:

api = SentinelAPI(user, password, "https://scihub.copernicus.eu/dhus")

gjPath = "Data/files_geojson/map.geojson"

gdf = geopandas.read_file(gjPath)

print(gdf)

footprint = None
for i in gdf["geometry"]:
    footprint = i
#("20190601", "20190626")
products = api.query(footprint, date=("20190601", "20211201"), platformname="Sentinel-2", processinglevel="Level-2A")

productsGDF = api.to_geodataframe(products)

print(productsGDF)

for i, product in enumerate(products):
    print("Product '", i, "'")
    if api.is_online(product):
        print("Product:", str(product), " is online.")
        api.download(product, directory_path="Data", checksum=True)

I don't understand if I need to guide the API to make a request or something, for the product be really available, but the documentation seems to say you can just go for it, plus I don't really know what checksums mean, apparently some sort of transfer verification.

Oz_Magician
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  • "some sort of transfer verification." Exactly. I'd try downloading the file without the checksum and then try to understand weither there is any corruption in that file. Might be a single byte that is wrong. – Sebastian Wagner Jun 08 '22 at 21:42
  • Huh, yeah that did work, and I suppose the content of the file is right, problem is it is downloading at really slow speed tho unfortunately, don't know if it's correlated but likely not. The API's up to date, but no use :/ There was this thread https://github.com/sentinelsat/sentinelsat/issues/103 where it got solved by upgrading the library, but as I said it didn't work for me. Atleast I got one step further, thanks – Oz_Magician Jun 10 '22 at 00:07

1 Answers1

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Apparently problem is solved, continued some days later with different usage of json file, (without doing the geodataframe part) and the download with checksum download normally, I did have to wait days tho after the first initial change (because after it still downloded at slow speeds, just that with checksum enabled), I suppose it was both a problem of the way I used the data&api, plus some connection problems at the time.

Oz_Magician
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