Dear Developers,
thanks for the great work in developing SNAP. I am wondering that how could we import SAR data from sensors which are not yet listed and associated with SNAP? For example, there are few companies making their own SAR satellite constellations like ICEYE and producing SAR data. How can we read SAR data from these companies with SNAP? I know that SAR data from ICEYE are readable by SNAP. Is there any fixed format for SNAP to read external SAR data?
Best regards,
Qiang
Hello Qiang
There are many different formats in the wild. Not all can be supported, considering the limited amount of resources.
SNAP supports some generic formats, like NetCDF or GeoTiff.
If the SAR data is provided in these data formats SNAP can read them. But often the generic formats are not sufficient.
Due to its plugin framework, SNAP can be extended by data readers which support other formats.
There is a wiki page which describes how to implement a reader. Unfortunately, it lacks detailed information. We have it on our agenda to improve this documentation.
SNAP is an open-source project and in the code repositories implementation of serval readers can be found and used as example.
SNAP - ESA’s SentiNel Application Platform (github.com)
How to build SNAP from sources - SNAP - SNAP Wiki (atlassian.net)
This answers your core question.
You can implement it yourself or you can contract someone. One of the Teams working on SNAP and the toolboxes or someone else.
Another option is you tell us what you need, and ESA can decide that it will be put on the development agenda within the ESA contracts.
Ideally satellite providers would also donate readers for SNAP - as Marco commented it’s not feasible for ESA to support all possible sensors with a limited number of users (due to data access restrictions for example), I would suggest that users lobby satellite providers for sponsoring reader development, or team up together and create product format readers themselves as Community Plugins by following help and tutorials for reader generation.
Hello @marpet,
thank you very much for your informative reply. It answers my question very well. I will first try by myself to implement it. Meanwhile, I will also try to contact the SAR data provider about it. They may consider developing a reader for their data. Thanks a lot.
And we are here to help if you have questions or stumble upon problems.
Hello, marpet, there is a problem I wonder to consult. I have already transformed my own SAR data to Binary formatting, and I use the file/import/sar formats/generic complex tool to import it. The intensity figure seems right but the data imported do not have geo-coordinates.
I am looking forward to your reply.
Hi gaiyanf,
the generic complex reader reads only the binary data.
You can add GCPs to it and based on this create a new GeoCoding.
Or you have another product with the same extent, but which is geocoded.
Then you copy the data over to the product.
Alternatively, a dedicated reader would need to be implemented.
How to create a new product reader - SNAP - Wiki
For SAR it’s essential that metadata contains all the parameters required for terrain correction.
