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Known Issues ​

Empty brick threshold is not bit-depth aware ​

DatasetConfig.emptyBrickThreshold (default: 100) is compared against raw integer brick stats.

  • 8-bit: 100/255 ≈ 39% of range — reasonable
  • 16-bit: 100/65535 ≈ 0.15% of range — effectively no culling

Fix: Normalize the threshold to 0–1 and compare against (stats.max - window.min) / (window.max - window.min) using the dataset's actual value range from metadata.window.

Empty brick culling does not work for Zarr datasets ​

Brick stats (min/max) in the Zarr path are computed lazily during assembleBrick() in the worker and cached in brickStatsCache. The streaming manager calls isBrickEmpty before loadBrick, so getBrickStats always returns null on the first pass → isBrickEmpty returns false → all bricks are loaded regardless.

Culling only activates on re-visits via the CPU brick cache (i.e., after an eviction/reload cycle).

Fix options:

  • Add a stats-only pre-pass for the coarsest Zarr LOD (fetch and scan without storing full brick data)
  • Or accept the limitation and document it — Zarr culling is a future optimization

Empty brick threshold cannot be determined automatically without a pre-pass ​

The threshold is inherently dataset-dependent (CT air vs. fluorescence background have different distributions). Automatic determination requires either:

  • A histogram of brick max-values from the coarsest LOD (infrastructure already exists via onBaseLodLoaded)
  • Or a global stats pre-pass before streaming begins

Currently the value must be set manually. A conservative normalized default (e.g. 0.02) would be safer than the current 100.