@qglaude @marpet thank you for providing this information. After the discussion, @constantinevi and I decide to make a video and provide it to ESA.
@hriston_bg I think in both of my text descriptions as well as my figure, I expressed that we should replace the values under the threshold with zero. This is because we noticed that snaphu is unable to unwrap “NaN” pixels.
However, I also understand your point. To experiment, you can try to geocode the interferogram which has been filtered out low coherence pixels. You will find out that the pixels with zero value are turned into “NaN” in the geocoded product.
I suppose that although “zero” in the interferogram is an accepted value, it symbolizes no data value in a sense. I don’t know the actual mechanism so it is just my assumption. If anyone knows better than me, please feel free to correct me. I’d be very much appreciated.
Lastly, I finished the post of my experiment on the comparison of different coherence thresholds applied. Please check this link if you are interested in my experiment.
Again, any insight and suggestions are welcome! Thanks a lot.