Gaps between bursts in interferograms and final output

[Lukas-Scharf-PLUS]

Hi @scottstanie and everyone else,
I use COMPASS and dolphin (and also tried sweets) for the city of Vienna. Somehow at the edges of the bursts some gaps appear in the final velocity and some interferograms as well.

interestingly in the coherence raster, and similarity raster these gaps do not appear.
I processed years 2022-2024 (92 scences).
Do you have any clue why that happens and how to solve that problem?
Has anyone experienced similar problems?
Thank you already for your help!
Best, Lukas

[scottstanie]

hi, this generally happens from including one or more dates of bursts where Sentinel-1 had poor timing synchronization. it happened more frequently as S1A degraded in 2025 (i believe around May 1 2025 there was a known QC problem).
if you make tiny plots of all interferogram phases, it's likely there will be one or two culprit dates; you should reprocess after removing those

[scottstanie]

Hmm no I haven't seen that since early testing. maybe a reproducing script would be helpful here?

[Lukas-Scharf-PLUS]

Input:
I used the forked sweets where I updated dolphin to 0.42.8 and whirlwind to 0.10.0.
https://github.com/Lukas-Scharf-PLUS/sweets

I used that config basically:

sweets config
--start 2022-01-01
--end 2024-12-31
--track 73
--bbox
16.18099875016676 48.11744311620298
16.587587299348154 48.324307364563005
--work-dir ./
--out-dir ./downloads
--output ./sweets_config.yaml
--n-workers 2
--threads-per-worker 4
--dolphin.worker-settings.block-shape 128 128
--dolphin.output-options.strides.y 3
--dolphin.output-options.strides.x 6
--dolphin.unwrap-options.unwrap-method WHIRLWIND

so it ran COMPASS for these 5 bursts:
't073_154936_iw1'
't073_154936_iw2'
't073_154935_iw1'
't073_154935_iw2'
't073_154937_iw1'

and then dolphin with that config:
dolphin_config.yaml

[scottstanie]

I did indeed reproduce, thanks for the clear reproducer. Confused how this is popping up as I thought i remember solving this years ago #237 .... not sure if @mirzaees or @mgovorcin have seen this pop up too

[scottstanie]

Thank you @Lukas-Scharf-PLUS , see #751
I also saw the lines when processing just the first 6 months of your window; with the PR change i see this now

[Lukas-Scharf-PLUS]

thank you very much! I try that!