General GT Verification/Review

This is the general guide to reviewing a task — how to tell whether your own or someone else's annotation is actually finished and correct. The review principles are tool-agnostic; do the review in whatever program is current (today that's WebKnossos). The VAST and Omni sections below are kept as historical detail.

Use a 3D view to review hand-painted segmentation. Omni was a 3D viewer, and any 3D view still works well here — rotating the object makes mis-clicks and leftover "dust" from erasing obvious at a glance, which is hard to catch scrolling slice by slice.

Cell segmentation — VAST inspection

Check borders

Cycle up and down through the stack to gauge how accurate the coloring is near the borders. Note any segments with significant bleeding (coloring over the border) or undercoloring (not coloring all the way to the border).

Check for mergers & splits

Inspect each segment one by one: select a segment, then scroll through the relevant portion of the stack. Note any segment improperly joined with another (a merger), or any segment that should be merged with another but isn't (a split).

Check for missing segments

Cycle through the entire stack, paying careful attention to areas without segments. Note any object that was missed.

Decide whether to verify

• No border issues, no mergers/splits, no missed segments → verify the task and let the annotator know they did well.
• Any border issues, mergers/splits, or missed segments → do not verify; tell the annotator where to make corrections.

Experts don't necessarily need to correct their own mistakes — they just need to see them.

Cell segmentation — Omni inspection

Cycle through all segments and, for each, check that it:

• does not contain a merge error;
• is not part of a split error;
• has no undercoloring;
• has no overcoloring;
• has no hanging pixels that weren't erased completely;
• does not skip well-identified neighboring segments.

Appeal process

If a verification outcome is disputed, acquire assistance from a Verified Researcher.