Skip to content

Mask phase estimates without covariance support - #751

Open
scottstanie wants to merge 1 commit into
isce-framework:mainfrom
scottstanie:codex/fix-phase-link-nodata-upstream
Open

scottstanie wants to merge 1 commit into
isce-framework:mainfrom
scottstanie:codex/fix-phase-link-nodata-upstream

Conversation

@scottstanie

Copy link
Copy Markdown
Contributor

Change Summary

When a partially covered burst-edge cell has no valid samples for an acquisition, its coherence matrix has a zero diagonal. Phase linking can turn that empty estimate into unit magnitude and zero phase with temporal coherence 1, leaving seams in stitched interferograms. Mark these estimates as nodata while allowing a valid PS to fill them.

The fix uses covariance support rather than phase value, so supported zero-phase estimates remain valid.

On canis, a four-date, five-burst control using the unmodified development branch had 390 exact 1+0j pixels in each of six stitched interferograms. The upstream-based patch removed those pixels: 380 per interferogram were filled from overlapping bursts and 10 became nodata. Only those 390 pixels changed in each interferogram.

Validation: 207 phase-linking, SHP, and PS tests passed on CPU (16 skipped); Ruff checks passed. On GPU, 206 passed and one existing CRLB tolerance test failed identically on unchanged upstream; that test passed on CPU.

Related issue number

#748

Checklist

  • The pull request title is a good summary of the changes - it will be used in the changelog
  • Unit tests for the changes exist
  • Tests pass on CI
  • Documentation reflects the changes where applicable
  • My PR is ready to review

This branch has not been deployed

No deployments
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant