I have just started researching about the detection of oil spill and applying various algorithms. But I don’t know how to detect oil spill. I have downloaded data of S1 but oil spill not working. Can anyone show each step?
there are many topics on it:
- Oil Spill Detection settings
- Oil spill detection tool Sentinel-1
- Oil spill detection not running
- Oil Spills Detection
- Problem with SNAP - Sentinel-1 oil spill detection
- Getting oil spill bit mask in snap from SLC product
- Oil Spill Graph - Detection/Cluster Output Looks Wrong
Please see if one of them answers your questions. Otherwise, you can of course ask questions on specific things in here. Just ‘not working’ is a bit too general 
Youtube video on this:
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If you plan to use the oil spill detection algorithm that is included in SNAP, some steps could be:
- subset to your study area (this will reduce a lot processing time in further steps)
- speckle filter (my experience is that detection works better after speckle correction)
- Check reflectance properties of the ‘possible spill’ drawing a line trough it. Then check profile plot to see how reflectance changes (this will help you to decide some parameters for the oil spill detection algorithm)
- Run the oil spill detection algorithm of SNAP. Adjust the three parameters to your specific case. There are not default values. Usually the background window size will influence a lot the result.
- ellipsoid correction: to correct for SAR geometry
- now you can repeat the process with other parameters
Be aware that the tool will identify possible oil spill. Check literature for look-alikes phenomena
Hope it helps
M
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That sounds interesting - have you any more tips?
Thanks,
Conor
Hi I concede this is the right subject to write about this ,
I have 2-3 or more oil spill detection images ( Sigma0_VV_oil_spill_bit_msk) and i want to combine/fusion/assembly them how can i do this ?
Geocode them (Ellipsoid correction over ocean areas) and create a stack of all results (Coregistration > Stack Tools)
You can then make RGB composites, apply a PCA, work with thresholds in the mask manager or apply the change detection module od SNAP.
There are many options, depending on the kind of results you want to get. Maybe you can elaborate a bit more.
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Hi, I’m just learning to use snap software for oil spill purposes. I have followed the steps in this forum. I don’t know why the oil detection results are misinterpreted or there is an oil object but it is not detected. please help with advice regarding this.
Background Window Size: 5
Threshold Shift: 1-4 db
Minimum Cluster Size: 0.1 km^2
this I try threshold 0.018
I think you need a smaller background window so that inside this window the dark patch statistically matters.
Spatial Subset? for the 2 objects in question? I have tried, still not detected.
No subset, but within a window of 5 km the patch is not changing much to the overall statistics. Reduce the value to a smaller number and compare how the result changed.
OK, I’ll try. Can I send the sentinel image that I have, to see the results of your processing?
sorry, I don’t have time to re-create your analysis. But you should be able to find out a suitable configuration by systematically changing the parameters and comparing the outcomes.
Thanks for the instructions, I’ll try it.
Unfortunately, Oil spill detection does not work today with SNAP…
I am running SNAP 9.0.8 on Ubuntu (BTW what a shame that on such an OS, the same name is used for package manager. Never mind.)
The idea is to try to replicate what can be seen here:
Oil spill Corsica 2018
A single product can be used to visualise the oil spill, for instance:
S1A_IW_SLC__1SDV_20181008T052755_20181008T052822_024040_02A081_3524.zip
In SNAP, you can navigate to Radar > SAR Applications > Ocean Applications >
Oil Splill Detection.
It opens a dialogue that shows the steps and the options of a Graph-file that
should be able to run and do the job.
Now, the original “Read” step works fine.
The problem comes from the next step: “Land-Sea-Mask”. It generates an error:
“The multi-size source product is not supported.Please, use resampling processor before. Or use the default graph 'Raster/Land Sea Mask For Multi-size Source.xml’in the graph builder.”
Nobody seems to refer to this issue.
What can be done from there to solve the problem is not obvious if you are not
an expert.
Would you be able to explain the different steps to implement a simple oil
spill detector with SNAP?