OpenSlide is a C library for reading whole slide image files (also known as virtual slides). It provides a consistent and simple API for reading files from multiple vendors.

OpenSlide can read brightfield whole slide images in several formats:

• Aperio (.svs, .tif)
• DICOM (.dcm)
• Hamamatsu (.ndpi, .vms, .vmu)
• Leica (.scn)
• MIRAX (.mrxs)
• Philips (.tiff)
• Sakura (.svslide)
• Trestle (.tif)
• Ventana (.bif, .tif)
• Zeiss (.czi)
• Generic tiled TIFF (.tif)

OpenSlide can also provide access to ICC profiles, textual metadata, and associated images such as a slide label and thumbnail.

The API reference is available on the web, and is also included as doc/html/openslide_8h.html in the source tarball. Additional documentation is available on the OpenSlide website.

OpenSlide is released under the terms of the GNU Lesser General Public License, version 2.1.

OpenSlide is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

To build OpenSlide, you will need:

• GCC or Clang
• Meson
• cairo ≥ 1.2
• glib ≥ 2.56
• libdicom ≥ 1.2 (automatically built if missing)
• libjpeg-turbo ≥ 1.3 or libjpeg ≥ 9c
• libpng
• libtiff ≥ 4.0
• libxml2
• OpenJPEG ≥ 2.1
• SQLite ≥ 3.14
• zlib
• Zstandard

Then:

meson setup builddir
meson compile -C builddir
meson install -C builddir

OpenSlide has been developed by Carnegie Mellon University and other contributors.

OpenSlide has been supported by the National Institutes of Health and the Clinical and Translational Science Institute at the University of Pittsburgh.

Development of DICOM and ICC functionality was supported by NCI Imaging Data Commons and has been funded in whole or in part with Federal funds from the National Cancer Institute, National Institutes of Health, under Task Order No. HHSN26110071 under Contract No. HHSN261201500003l.