Is there any mistakes?
could be that the pixels outside the extracted area are zeroes. And therefore occupy nearly the same disk space. Is clipping outside snap an option?
Yes, they are all zeros. And I’ll try to find other options. You are really great and helpful! Thank so much!
Because i want to estimate the water volume in lakes and reservoirs,and some of them located in different images.But the data volume is so big, so i have to think about subset them into smaller pieces and then mosaic. I’ve tried subset tool and Land/Sea Mask
Hi Ellachang,
I am also interested in studying S1 SAR- based reservoir estimation for my master thesis. Could you share with me some experience in this field.
Now I am using S1 GRD data with pre-process steps: subseting -> calibration -> terrain correction -> speckle filter (Lee Sigma). Is it ok for the pres-process? And what method have you used to define threshold of image to classify image to water and non-water class?
I am quite new in this field, so I very appreciate any suggestion from you.
Thanks in advance.
It is better to speckle-filter before terrain correction.
Hi mengdahl,
Thank you for your response. Do you have any suggestion for method of speckle filter? I see many kind of method in speckle filtering toolbox but I do not have much understanding of their application. In case of water detection, do you know what method should be applied?
recommending a filter is nearly impossible because they strongly relate on pixel size, surface and the degree of speckle. Best solution is to systematically try and compare some filters, window sizes (and sometimes other parameters) on a small subset and successively finding the one that suits your conditions the best.
Regarding the water detection, these are quite helpful pages:
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Hi, ABraun, if Calibration > Multilooking, the image is empty? I don’t know why,
Can’t judge based on this few information, sorry.
OK，Thank you！I have another question, how to generate VV/VH Formatted data,
can you please explain more clearly what you mean?
When you download S1 images VV and VH polarizations are already present. Maybe these tutorials help you: http://step.esa.int/main/doc/tutorials/sentinel-1-toolbox-tutorials/
can generate vv or vh, but not vv/vh, Some people use vv/vh to calculate the biomass,
right-click the product and select RGB composite
Yes! Thank you very much!
Hello,I have a question to ask you, and I am very happy to get your help .
My question is how to use the “Band math” to get the result of “slope normalisation” and get the picture about the relationship between the “Angle of Incidence” and "Backscattering Coefficient " just shown in the obove.
thanks for you help.
I am a beginner who studies SAR. I take the liberty to bother you. I can’t download the Sentinel-1 toolbox tutorial. Can you send me these three tutorials? I found your comment in the forum.
you find numerous tutorials here:
Thank you very much！