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Check if file is valid NRRD file

Since R2022b



tf = isnrrd(filename) checks if the specified file is a valid nearly raw raster data (NRRD) file.


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Check whether a file is a valid NRRD format file. The file is part of a data set containing the 3-D CT and MRI scans from The Retrospective Image Registration Evaluation (RIRE) Dataset, converted to the NRRD file format. The original data set was provided by Dr. Michael Fitzpatrick. For more information, see the RIRE Project homepage. The size of the entire data set is approximately 35 MB. Download the data set from the MathWorks® website, then unzip the folder.

zipFile = matlab.internal.examples.downloadSupportFile("medical", ...
filepath = fileparts(zipFile);

Specify the name of the NRRD file to check.

filename = fullfile(filepath,"supportfilesNRRD","Patient007CT.nrrd");

Check if filename is a valid NRRD file. The isnrrd function determines that the file is valid.

ans = logical

Input Arguments

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Name of the NRRD file, specified as a string scalar or a character vector. The file must contain a valid NRRD file header. filename can contain the absolute path to the file, a relative path from the current directory, or a relative path from a directory on the MATLAB® path.

Data Types: char | string

Output Arguments

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File is a valid NRRD file, returned as a logical 1 (true) or 0 (false). The output value is 1 if filename contains a valid NRRD header. The function can determine the validity of NRRD files that contain image data or are detached header files.

Version History

Introduced in R2022b

See Also