Feature request: Segmentation outlines in the viewer

[lpelkmans]

The segmentation outlines visible in the viewer are simplified compared to the actual segmentation results. I understand the purpose of this: to allow for faster loading times. However, it defeats the purpose of using pyramids, namely to be able to zoom in to the highest resolution and evaluate finer details of the images/cells. An important part of such an evaluation is to see how well the segmentation worked across large sets of images.

Could one have segmentations with the full details? Could one have them increase detail as one zooms in? Or switch from the less-detailed to the more-detailed once at a certain zoom-in level?

Will certainly improve the viewer's functionalities.

[hackermd]

This is already implemented in the master branch and will be available with the next 0.2.0 release.

I implemented the approach you outlined:

• exact outlines are saved for each segmented object in form of a polygon (ST_Polygon), such that the original segmentation image can be re-created
• for visualization, these polygons are simplified in a zoom-level dependent manner (ST_SimplifyPreserveTopology)

Note, however, that by default, there is still some simplification even at the maximum resolution level:

tolerance = (maxzoom - z) ** 2 + 1

This is done to ensure a smooth user experience. However, we could implement it such that the user can change the tolerance parameter and thereby enforce full resolution.