The AIR (''Automated Image Registration'') is a program suite for volume-based
image registration
Image registration is the process of transforming different sets of data into one coordinate system. Data may be multiple photographs, data from different sensors, times, depths, or viewpoints. It is used in computer vision, medical imaging, milit ...
constructed by
Roger P. Woods from
UCLA School of Medicine
The University of California, Los Angeles School of Medicine—known as the David Geffen School of Medicine at UCLA (DGSOM)—is an accredited medical school located in Los Angeles, California, United States. The school was renamed in 2001 in h ...
.
It reads and writes
Analyze volume files and can work with 4x4
transformation matrices stored in its own file format with the
filename extension
A filename extension, file name extension or file extension is a suffix to the name of a computer file (e.g., .txt, .docx, .md). The extension indicates a characteristic of the file contents or its intended use. A filename extension is typically d ...
.air.
It is especially designed for
neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive manner. Incre ...
applications and has primarily been used in research-oriented
functional neuroimaging
Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions. It is primarily used a ...
with brain scans from
positron emission tomography
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in Metabolism, metabolic processes, and in other physiological activities including bl ...
and
magnetic resonance
Magnetic resonance is a process by which a physical excitation (resonance) is set up via magnetism.
This process was used to develop magnetic resonance imaging and Nuclear magnetic resonance spectroscopy technology.
It is also being used to ...
scanners.
The suite provides a number of programs for image registration with different transformation models, such as rigid-body, affine and nonlinear
warping.
For example, for affine transformation the registration from one brain scan to another may be found with the ''alignlinear'' program and written to the special air-file that stores the transformation matrix.
The transformation may be inverted with the ''invert_air'' program and the volume may finally be resliced and interpolated with the ''reslice'' program.
External links
Automated Image Registration— homepage for the fifth version of the program suite
Medical imaging
Neuroimaging software