Quantization in Multispectral Color Image Acquisition

For applications where colorimetric information is insufficient to characterize an input scene or document, multispectral image capture (i.e. for more than three records) has been suggested. Experimental cameras have been described, as have the results of signal processing to extract useful spectral and colorimetric information. Previous reports have addressed both system accuracy and precision, the latter as influenced by random pixel-to-pixel image noise. Another contributor to system precision is signal quantization. Statistics are computed for various levels of uniform and non-uniform quantization. The resulting errors in the estimated object spectral reflectance factor and subsequent colorimetric transformation are addressed. The comparison of these errors with those due to stochastic noise sources indicates that both are influenced by the image processing employed.