Furthermore, the size of the Crizotinib PF-2341066 objects present in multiple images is not necessarily conserved. The correlation map provided by 2-DFFT indirectly allows for the evaluation of translations, rotations and scale changes between images. Image mosaicing results, i.e., translations, rotations and scale changes between couples of consecutive images, were finally used for correctly assigning the line acquired with the spectrometer within the investigated area. The application of Fast Fourier Transform for frame fusion techniques, in particular within super-resolution algorithms to reconstruct high resolution images from a series of low resolution images is presented in [9]. To the authors knowledge, FFT is used here for the first time to automatically mosaic thousands of images and georeference spectrometer data.
The accuracy of this method is carefully investigated using portions of a sample image that are transformed using rotation and a change of scale to test the ability of the algorithm to detect the correct extent of superposition.This paper is organized as follows: Section 2 describes the hyperspectral device with two spectrometers. Section 3 presents an outline of image mosaicing issues and describes the novel algorithm. Sections 4 and 5 describe the algorithm performances evaluated using a sample image and image sequences acquired during a proximal sensing field campaign conducted in San Teodoro (Olbia-Tempio��Sardinia), respectively. Possible algorithm improvements are discussed in the concluding section.2.
?Hyperspectral Device with Two SpectrometersThe hyperspectral system is based on the use of two spectrometers (Figure 2); the first spectrometer (VIS) is centered in the visible range of the electromagnetic spectrum (400 nm to 1,000 nm), Carfilzomib and the second spectrometer (NIR) is centered in the near infrared region (from 900 nm to 1,800 kinase inhibitor Ixazomib nm). Each spectrometer captures a line image of a target and disperses the light from each line image pixel into a spectrum. Each spectral image contains then line pixels in a spatial axis and spectral pixels in a spectral axis. A 2D spectral image sequence can be formed by sequentially acquiring images of a moving target or by moving the push broom spectral device.Figure 2.Sketch of a spectrometer [4].