openslideinfo

Read whole slide image file metadata using OpenSlide library

Since R2026a

Syntax

info = openslideinfo(filename)

Description

Add-On Required: This feature requires the Medical Imaging Toolbox Interface for Whole Slide Imaging File Reader add-on.

info = openslideinfo(filename) reads the metadata from the whole slide imaging (WSI) file filename using the OpenSlide library and returns the metadata structure info.

Examples

Read Metadata from Whole Slide Image Using OpenSlide

Run this code to download a whole slide image from the MathWorks® website, and unzip the downloaded folder. The image, stored in the NDPI format, contains an H&E stained microscopy slide provided by the OpenSlide library test data set [1].

zipFile = matlab.internal.examples.downloadSupportFile("image","data/CMU-1.zip");
filepath = fileparts(zipFile);
if ~exist(filepath)
    unzip(zipFile,filepath)
end
filename = fullfile(filepath,"CMU-1.ndpi");

Read the metadata from the file. The function returns a structure, info, that contains fields for the filename, vendor name, associated images, and raw metadata.

info = openslideinfo(filename);

The AssociatedImages field specifies which, if any, associated label, macro, or thumbnail images are present in the file. In this example, the file contains a macro image, which provides a low-resolution overview of the full slide.

info.AssociatedImages

ans = 
"macro"

The RawMetadata field contains the raw metadata that the OpenSlide library finds in the file. The exact attributes in the raw metadata vary between file formats and imaging setups. In general, the metadata specifies the image dimensions, size, and microscope acquisition settings. Many whole slide images are tiled and contain multiple downsampled resolution levels, so the metadata might also specify the tiling and image pyramid scheme.

info.RawMetadata

ans = struct with fields:
                 hamamatsu_SourceLens: 20
     hamamatsu_XOffsetFromSlideCentre: 4876667
     hamamatsu_YOffsetFromSlideCentre: -2340000
    openslide_associated_macro_height: 408
     openslide_associated_macro_width: 1191
                openslide_level_count: 9
         openslide_level_0_downsample: 1
             openslide_level_0_height: 38144
        openslide_level_0_tile_height: 8
         openslide_level_0_tile_width: 2048
              openslide_level_0_width: 51200
         openslide_level_1_downsample: 2
             openslide_level_1_height: 19072
        openslide_level_1_tile_height: 4
         openslide_level_1_tile_width: 1024
              openslide_level_1_width: 25600
         openslide_level_2_downsample: 4
             openslide_level_2_height: 9536
        openslide_level_2_tile_height: 8
         openslide_level_2_tile_width: 512
              openslide_level_2_width: 12800
         openslide_level_3_downsample: 8
             openslide_level_3_height: 4768
        openslide_level_3_tile_height: 4
         openslide_level_3_tile_width: 256
              openslide_level_3_width: 6400
         openslide_level_4_downsample: 16
             openslide_level_4_height: 2384
        openslide_level_4_tile_height: 8
         openslide_level_4_tile_width: 128
              openslide_level_4_width: 3200
         openslide_level_5_downsample: 32
             openslide_level_5_height: 1192
        openslide_level_5_tile_height: 4
         openslide_level_5_tile_width: 64
              openslide_level_5_width: 1600
         openslide_level_6_downsample: 64
             openslide_level_6_height: 596
        openslide_level_6_tile_height: 596
         openslide_level_6_tile_width: 800
              openslide_level_6_width: 800
         openslide_level_7_downsample: 128
             openslide_level_7_height: 298
        openslide_level_7_tile_height: 298
         openslide_level_7_tile_width: 400
              openslide_level_7_width: 400
         openslide_level_8_downsample: 256
             openslide_level_8_height: 149
        openslide_level_8_tile_height: 149
         openslide_level_8_tile_width: 200
              openslide_level_8_width: 200
                      openslide_mpp_x: 0.4564
                      openslide_mpp_y: 0.4551
            openslide_objective_power: 20
                openslide_quickhash_1: "f14cd7dcf9dff2b7b3551672a1f3248bd35cc4a2e57e3ca47a2b83eac9ad3987"
                        tiff_DateTime: "2009:12:31 09:11:46"
                            tiff_Make: "Hamamatsu"
                           tiff_Model: "NanoZoomer"
                  tiff_ResolutionUnit: "centimeter"
                        tiff_Software: "NDP.scan"
                     tiff_XResolution: 21910
                     tiff_YResolution: 21975

Input Arguments

filename — Name of file

string scalar | character vector

Name of the file, specified as a string scalar or a character vector. Specify filename as the absolute path to the file, a relative path from the current directory, or a relative path from a directory on the MATLAB^® path.

The file must be in a format supported by the OpenSlide library. For a list of supported formats, see Virtual Slide Formats Understood by OpenSlide in the OpenSlide documentation.

Data Types: char | string

Output Arguments

info — File metadata

structure

File metadata, returned as a structure that contains these fields.

Field	Description
Filename	The full path to the file.
Vendor	Information about the instrument used to acquire the image.
AssociatedImages	List of related images in the file, such as thumbnails or low-resolution overviews.
RawMetadata	Detailed raw metadata from the file. The content of the raw metadata depends on the file format and imaging setup.

References

[1] "CMU‑1.ndpi". OpenSlide Test Data. Accessed November 10, 2025. https://openslide.cs.cmu.edu/download/openslide-testdata/Hamamatsu/.

Version History

Introduced in R2026a