Look@MOSI is a software for the analysis of hyperspectral images obtained by the MOSI system. It offers functions that are common in commercially or freely available programs for hyper-spectral data analysis. Additionally, Look@MOSI offers features that are not that usual, such as the possibility to pixel-wise calculate 2nd and 4th derivatives of smoothed spectra, or their base-10 logarithm, and display them as an image.
Some details of the program can be found in the paper by Polerecky et al. (2009) published in Applied and Environmental Microbiology, which describes the MOSI system. You can download the published PDF (need subscription), Supplementary material (free).
More results obtained by the program can be seen in papers listed here.
See a gallery of images generated by the Look@MOSI software.
If you are interested in using the program, you can download it from here.
This is only a very quick introduction to the program, sort of like a crash-course.
eye buttonto view the image in the corresponding channel. Double left-click on the image to rescale the colormap, right-click on the image to save it into BMP. Note that smoothed values of the spectral signal can also be plotted.
Open button, and define reference region dimensions. Note: use left=0 and right=480 in version 0.43+, top and bottom can be chosen arbitrarily within the image dimensions. Then click on the
Save referencebutton to calculate vertically averaged spectra in the region and save them into a BIP file. If you have previously saved some other reference regions, click on the
Load referencebutton to load it. Finally, click OK. Leave the checkbox in the main window checked if you want to display spectra normalised to the reference spectra, leave it unchecked if you want to display directly measured spectra.
Show spectral viewerbutton (the icon with the graph and red/blue lines) to display the spectrum in a selected pixel. Observe the changing shape of the spectra as you move with the mouse over the R, G or B image (see 3). Double left-click on the
Spectral viewergraph to rescale it.
Average spectrabutton to display the average spectrum. Then click on the
Save buttonto save it into a DAT file. Check the checkbox if you want to display more than one spectrum in the graph.
Open filebutton. Check the first checkbox, then define the filename, then check the second checkbox and define the second filename, etc. Do not skip the vectors, i.e., do not define for example v0 and v2 with v1 being undefined! Click OK when you are ready with the definition of all pure spectral vectors to load them. Observe how these spectra are also being displayed while you move the mouse over the R, G or B image, as described in 4. The fitting spectrum, given by the linear combination of the pure spectra (the coefficients c0, c1, … are also displayed), is displayed (gray) along with the measured spectrum (white).
Decompose HS imagebutton to decompose the measured spectra into pure spectra in each pixel. This will effectively calculate the images of coefficients c0, c1, … (see 7) characterizing the “intensity” distribution of the pure spectra across the image. To view these coefficients, click on the corresponding
Show pure spectrum distributionbuttons. Double left-click on the image to rescale the colormap, right-click to save it into a BMP file.
Display derivativeto 2 or 4 and click on the “eye button” to display spectral derivative. Note that you may need to change the scale of the image (not the spectra, as this remains the same) to see it correctly. When you want to display the image derived from the original spectra, select 0 derivative.