One of the requirements for file formats mentioned earlier was a software interface to make the interface easy to use. The biggest difficulty in using a flexible format is that the application must handle many possibilities. Where images are concerned, this means various data types and scale factors, and images of differing sizes. The image conversion variable functions of MINC attempt to remove this complication for the programmer.
An image conversion variable (icv) is essentially a specification of what the program wants images to look like, in type, scale and dimension. When an MINC image is read through an icv, it is converted for the calling program to a standard format regardless of how data is stored in the file.
There are two categories of conversion: Type and range conversions
change the datatype (and sign) of image values and optionally scale
them for proper normalization. Dimension conversions allow programs to
specify image dimension size and image axis orientation (should
MIxspace coordinates be increasing or decreasing? should the
patient's left side appear on the left or right of the image?).