Sentinel-2 Classification Problem

Optical Toolbox
#7

I don’t know but I have same problem in SNAP 6.0. Do you have any tutorial or user guide for sentinel-2 classification procedure in SNAP software?

I saw many video tutorials in youtube but they didn’t use sentinel-2 images.

Sincerely,

#8

how did you resample the subset?
When I run the S2 Resampling operator on the subset product (it does work, you’re right), I get this message:
grafik

Maybe you first run the S2 Resampling operator and create a subset afterwards. This takes longer, but worked for me in the past.

#9

I don’t have any problem in resampling operator and it works well. I’m following these steps:

  1. download S2 L2A
  2. open in snap 7
  3. spatial subset using subset operator
  4. resampling suing resampling operator: make all bands same pixel size.
  5. collecting training data from resampled data
  6. open Random Forest Classification
  7. insert data
  8. select training data
  9. select bands
  10. defining output address
  11. run
  12. processing completed
  13. shows bad result!
#10

It was reported here that Sentinel-2 data has to be reprojected to WGS84 before collecting the training data and applying the classification:

1 Like
#11

a few minute ago I’ve tried random forest classification for landsat data and it works well without any problem. I think coordinate system cause this problem, according to this now I’m gonna to check sentinel-2 coordinate system and I will share you final result.

Sincerely,

#12

Dear Braun

When I changed sentinel-2 coordinate system to wgs84, classification problem has solved completely.

Thanks for your excellent support.

Sincerely,

1 Like
Supervised Classification Error
Rndom forest classification steps
Supervised Classification Problems on Landsat 8 scene
Classification problem (nullpointerexception)
Blank screen result after supervised classification
Forest species classification
MTD_MSIL1C
No image after reprojection
Classification - empty frequency values in LabelledClasses
Random Forest Classification
Issues with Supervised classification in SNAP
Vectors do not save to the product
Supervised classifications fail
#13

good to hear, thank you!

#14

dear Amirhossein ,I classifed with sentinel-2 images too .but i didn’t work the step that Subset raster.Is this step necessary

#15

Dear AmirHossein,
Can you clarify a bit more about the sentinel 2 image classification in snap 7. I am new to this kind of Sentinel2 classification. I will be so thankful if you give more details about your workflow. cheers, Farman

#16

please have a look at these instructions:

#17

Thanks ABraun for your swift reply on my issue. I will have a deep look at it and let you know with my results… Cheers

#18

Dear sir .There is no surface reflectance document for Sentinel-2, and I would like you to recommend me .

#19

every Sentinel-2 product contains refleactance. These instructions are valid for all multispectral products.

#20

image
here?I mean that files what can help me to identify the different figure types.

#21

please try to use the search function, many things are already explained in other topics: The "dl" unit

#22

can you please help me with that ? i did reprojection with utm/wgs84 and its still having issuees

#23

hi there;
when i tried reprojection, i don’t know why it doesn’t work i receive an error . by the way I’m in morocco.
can u please help me and tell me how i can do the reprojection

#24

Please share the error message, otherwise we cannot help.

#26

2021-12-16 (3)
2021-12-16 (3)1366×768 195 KB

#28

This happens if your PC does not habe enough RAM.
HAve a look in the SNAP FAQs. There it is explained how you can tweak the memory settings. But probably you will need a machine with more memory.