Slide readers and formats

LazySlide delegates WSI reading to wsidata. Format support therefore depends on the installed reader and the exact vendor encoding.

Reader	Typical use	Additional requirements
TiffSlide	TIFF-based bright-field WSI formats	Python package; installed by default
OpenSlide	Common vendor bright-field formats	OpenSlide library and Python bindings
fastslide	High-performance native whole-slide image reading	fastslide
Bio-Formats	Broad microscopy format coverage	Java and scyjava
cuCIM	Supported GPU-accelerated image I/O	Compatible NVIDIA/CUDA environment
pyisyntax	Philips iSyntax pathology images	pyisyntax and libisyntax support
pylibCZIrw	Zeiss CZI, including native JPEG-XR decoding	Platform-compatible pylibCZIrw wheel

The common extensions include .svs, .ndpi, .mrxs, and TIFF variants, but an extension is not a complete compatibility guarantee.

Verify a file

import lazyslide as zs

wsi = zs.open_wsi("path/to/slide")
print(wsi.properties)
print(wsi.fetch.pyramids())

Inspect the selected reader, dimensions, physical pixel size, magnification, and pyramid levels. Test representative files from every scanner and acquisition protocol used in a cohort.

Annotation formats

zs.io.load_annotations reads geospatial files supported by GeoPandas, including QuPath GeoJSON, and Hamamatsu .ndpa files. Export currently targets QuPath-compatible GeoJSON. See Annotations.

For reader installation commands, see Installation.