2_dem_generation no 'getMetadataRoot()' attribute

[vdevauxchupin]

Hello,

I am discovering your pipeline as I would like to generate DEMs for a glacier in Alaska. I tried different AOIs, different times and sizes, and I am always blocked at the same step: generating the DEMs with 2_dem_generation.py.

The script encounters the following error:

Traceback (most recent call last):
  File "/scripts/2_dem_generation.py", line 941, in <module>
    subset_buffer=args.aoi_buffer
  File "/scripts/2_dem_generation.py", line 683, in run_P1_interferogram
    pass_metadata_p1 = product_1.getMetadataRoot() \
AttributeError: 'NoneType' object has no attribute 'getMetadataRoot'

I traced it back to SNAP, and concluded that it could come from bad images, but even after changing AOI and time-window I still got the same issue. Depending on which AOI or which time-window I use, I get between 2 and 10 .zip images.

Have you encountered that issue before ? If not, could you recommend an area that you know that works well with the code ?

Thank you !

ps: it's awesome to see people finally creating a pipeline for SAR DEM generation !!

[loreabad6]

Hi @vdevauxchupin, thank you for pointing me to this issue. I am very happy more people find the pipeline useful 😄

I tested with my study areas and the script works rather fine. It could indeed be the time frame or AOI, would you mind shring which dates, or even which scene IDs you are getting the error from?

[vdevauxchupin]

I chose a timeframe going from 01/05/2020 to 30/06/2020. It downloads 5 images in total I think

[loreabad6]

Hi @vdevauxchupin, sorry for the late come back, I suspect this has something to do with the image itself. Do you have some scene IDs that give you trouble so I can test on my end?
We use for example these pair in Norway without issues:

• S1A_IW_SLC__1SDV_20210715T170238_20210715T170305_038791_0493BD_2474
• S1B_IW_SLC__1SDV_20210709T170154_20210709T170221_027720_034EDE_EA73

[vdevauxchupin]

Hi, no worries !
Two IDs I had were:

• S1A_IW_SLC__1SDV_20200420T154830_20200420T154856_032213_03B9D0_2665

• S1A_IW_SLC__1SDV_20200514T154831_20200514T154858_032563_03C586_D725

(I was using the SBAS system of vertex manually to find the smallest temporal baseline for the biggest spatial baseline)

Maybe I just messed up my docker installation, it could also be that!