The automatic alignment and mosaic of video frames from the variable interference filter imaging spectrometer

Abstract

The variable interference filter imaging spectrometer (VIFIS), is a modified video‐based remote sensing instrument. The creation of a hyperspectral cube for a flight line from the VIFIS instrument relies on the successful alignment and mosaic of sequential video frames. A number of techniques have been tested to assess which is the most reliable at finding accurately matched positions between sequential frames. Results show correlation techniques to be more successful than ordinal measures and invariant moments. Once a list of matching points had been created the transform between frames can be calculated and a mosaic generated. The application of an affine transform between every frame led to severe distortions in the imagery and rendered the final product useless. Experiments have shown that an affine transform was not required in each case and should only be applied when it provides an improvement over the mapping provided by a lower level transform.