All reconstructed data is stored as an AxisArray. The AxisArrays package is part of the Images package family, which groups all image processing related functionality together. We note that the term Image does not restrict the dimensionality of the data types to 2D but in fact images can be of arbitrary dimensionality.

The reconstructed MRI image I is an AxisArray and has five dimensions. The first three are the spatial dimension x, y, and z, whereas dimension four encodes the number of echos that have been reconstructed, while dimension five encodes individual coils that may have been reconstructed independently. By using an AxisArray the object does not only consist of the data but it additionally encodes the physical size of the image as well as the echo times. To extract the ordinary Julia array one can simply use

The advantage of encoding the physical dimensions is the image data can be stored without loosing the dimensions of the data. For instance one can call

saveImage(filename, I)

to store the image and

I = loadImage(filename)

to load the image. Currently, MRIReco does support the NIfTI file format. By default, saveImage stores the data complex valued if the image I is complex valued. To store the magnitude image one can call

saveImage(filename, I, true)