I’ve never had to use SNAP to generate InSAR files until last week when a coworker resigned. I’ve never dealt with imagery processing and I am going off of a brief manual left behind by a previous coworker who processed InSAR files. According to the last two people who used SNAP version 6.0 to generate InSAR files, the first step “S1 TOPS Coregistration” should take approximately 15-20 minutes to run, but I am at hours/days of letting the process run on a virtual machine. One of the previous users advised me to store the original files and all files generated by the process on my desktop then migrate to our server to help speed things up but this has not helped.
I am remote-connecting to the previous co-worker’s desktop because they claimed this first step ran no longer than 45 minutes for them, but I started the process yesterday afternoon and now after nearly 24 hours the progress bar is still only at 14%.
The desktop I’m remoting into to run the process is a 64-bit PC with 32GB of RAM, which checking the required specs of the software this machine meets all of them.
Does anyone have any advice of what I can try to get this first step “S1 TOPS Coregistration” to run at the supposed appropriate time of 15-20 minutes? Thank you all for your time.
Firstly, this is related to a change of DEM online resources, please check here: A process related to digital elevation models is taking forever to finish
So, we highly recommend to upgrade to SNAP 8 and install all updates.
If it still takws long, please have a look at this FAQ entry: S1 TOPS Coregistration takes much time or even fails
Thank you for your response. I found a solution on another thread you had commented on and my process so far is working much faster now.
I have a follow-up question: I’m now down to a step called “Goldstein Phase Filtering”, all the person left behind was “Start with default parameters, adjust if result is over or under filtered”. How do I know or how can I check my filtering result, and what determines if the result is over or under filtered?
An example of over filtering is given in the table at the end of this tutorial: DEM generation with Sentinel-1 - Workflow and challenges
Under filtering means that there is still some noise in areas where it could be reduced. This doesn’t apply for completely decorrelated areas though.
So the filtering should improve the quality of the fringes without introducing new artefacts.
How do I get to the viewing window that is shown in the Goldstein Phase Filtering (hopefully successfully shown below). As I mentioned this process was dropped into my lap without even a basic tutorial of where everything is, and that image that shows the before and after, I don’t know where to see those windows.
Thank you so much for your quick responses and your patience, I really appreciate it.
You first calculate the product and then double click the phase image inside it (under Bands)
SNAP6.0 is not supported, please upgrade to 8.x.