Colony counting is a procedure used in microbiology laboratories for food quality monitoring, environmental management, etc. Its purpose is to detect the level of contamination due to the presence and growth of bacteria, yeasts and molds in a given product. Current automated counters require a tedious training and setup procedure per product and bacteria type and do not cope well with diversity. This contrasts with the setting at microbiology laboratories, where a wide variety of food and bacteria types have to be screened on a daily basis. To overcome the limitations of current systems, we propose the use of hyperspectral imaging technology and examine the spectral variations induced by factors such as illumination, bacteria type, food source and age and type of the agar. To this end, we perform experiments making use of two alternative hyperspectral processing pipelines and compare our classification results to those yielded by color imagery. Our results show that colony counting may be automated through the automatic recovery of the illuminant power spectrum and reflectance. This is consistent with the notion that the recovery of the illuminant should minimize the variations in the spectra due to reflections, shadows and other photometric artifacts. We also illustrate how, with the reflectance at hand, the colonies can be counted making use of classical segmentation and classification algorithms.
History
Volume
8225
Location
San Francisco, California
Start date
2012-01-21
End date
2012-01-26
ISSN
0277-786X
Language
eng
Publication classification
E1.1 Full written paper - refereed
Copyright notice
2012, SPIE
Editor/Contributor(s)
Farkas DL, Nicolau DV, Leif RC
Title of proceedings
SPIE BiOS 2012 : Proceedings of SPIE BiOS Conference on Imaging, Manipulation and Analysis of Biomolecules, Cells, and Tissues X
Event
SPIE BiOS - Imaging, Manipulation and Analysis of Biomolecules, Cells and Tissues X. International Conference (2012. San Francisco, California)
Publisher
S P I E - International Society for Optical Engineering