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Investigate if `ome-zarr-py` Labels class __init__ leads to performance implications

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Active
Tech stack
python
Domain
performance

Research direction

Start with the linked ome_zarr/classes/image.py location and inspect the Labels class init, especially the unique-value computation for the biggest label scale. Compare label-read behavior with and without that computation, then document whether it causes a slowdown and add regression coverage if the project provides a suitable test location.

Written by the indexing model from the issue text.

Description

performance 🚀

I noticed that the constructor of the Labels class in the recent ome-zarr-py release calls a function that computes unique values for the biggest scale of labels: https://github.com/ome/ome-zarr-py/blob/025e83da618ec9e74f4b41f05814fce07b029356/ome_zarr/classes/image.py#L1140

I haven't done regression tests on this, but let's keep an eye and see if this means that we are getting a slowdown upon read.

CC @ajkswamy @Tomaz-Vieira @melonora

Dominant language
Python
Stars
394
Forks
95
Avg merge
3d 9h
Merged PRs (30d)
5

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