Journal of Real-Time Image Processing

, Volume 1, Issue 1, pp 25–32 | Cite as

Spectral image processing in real-time

  • Matthias F. CarlsohnEmail author
Survey Paper


The fields of classical image processing and optical spectroscopy developed independently since a long time. While the first subject deals with pictorial information that uses the description of material by their surfaces in terms of brightness, texture and color depending on the illumination in the two dimensional field of view of the optics, the second one classifies usually material properties due to their radiation in particular spectral bands but mostly limited to a single point of the object’s surface. Combining imaging devices and spectrographs to record point spectra for entire surfaces of objects leads to the new and emerging field of spectral imaging. Using this technology in material sorting for recycling purposes introduces additional real-time constraints for the processing. First commercial solutions in this application field leverage breakthroughs also in other application fields and lift experimental set-ups to the shop floor maturity and robustness.


Spectral imaging Imaging spectrograph Dispersive optical element NIR-spectroscopy Real-time material sorting 





Near infra-red




Visual spectral range


Modulation transfer function


Charged-coupled device


Spectral imaging




Region of interest


Spectral imaging


Red green blue




Magnetic resonance spectral imaging


Principal component analysis



Particular thanks are given to my colleagues from Carinthian Tech Research CTR in Villach Austria for their support and recommendations.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Engineering and Consultancy Dr. Carlsohn for Computer Vision and Image CommunicationBremenGermany

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