Improved imaging system for fecal detection

摘要

The Agricultural Research Service (ARS) has developed a hyperspectral imaging system to detect fecal contaminants on poultry carcasses. The system operates from about 400 to 1000 nm, but only a few wavelengths are used in a realtime multispectral system. ARS has reported that the ratio of reflectance images at 565 nm and 517 nm was able to identify fecal contaminants. However, this ratio alone also misclassified numerous non-fecal carcass features (false positives). Recent modifications to the system, including improved lighting, new camera, new spectrograph, and a new algorithm with an additional wavelength, have increased fecal detection accuracy while reducing the number of false positives. The new system was used to collect hyperspectral data on 56 stationary poultry carcasses. Carcasses were contaminated with both large and small spots of feces from the duodenum, ceca, and colon, and ingesta from the crop. A total of 1030 contaminants were applied to the carcasses. The new algorithm correctly identified over 99% of the contaminants with only 25 false positives. About a quarter of the carcasses had at least one false positive.