read.nifti.values: Read raw voxel values of a NIFTI v1/v2 or ANALYZE file from a...

In freesurferformats: Read and Write 'FreeSurfer' Neuroimaging File Formats

Read raw voxel values of a NIFTI v1/v2 or ANALYZE file from a connection.

Description

Read num_values voxel values of the data type described by the datatype and bitpix fields of a header, in the endianness of the file. This is the shared low level reading code of the NIFTI and ANALYZE readers.

Usage

read.nifti.values(fh, datatype, bitpix, num_values, endian)

Arguments

fh	connection to read from, positioned at the first value.
datatype	integer, the datatype header field.
bitpix	integer, the bitpix header field.
num_values	integer, the number of values to read.
endian	character string, the endianness of the file, 'little' or 'big'.

Value

numeric or integer vector of length num_values, the raw values as they are stored in the file.

Note

The signedness of the data type is taken from nifti.dtype.info: an unsigned 8 bit value of 200 is returned as 200, not as -56. R's readBin reads integers as signed by default, and it silently ignores a signed argument for 4 byte integers, so the three unsigned types need special care.

freesurferformats documentation built on Sept. 25, 2026, 1:07 a.m.