Hyperspectral cameras are optical instruments that are designed for capturing spatial information from a scene in such a way that each pixel contains the spectrum of the corresponding small scene area. One of the important factors when assessing camera performance, is the amount of spatial and spectral information in the acquired hyperspectral data. Traditionally, these are directly communicated to users as spatial pixel count and spectral band count. However, depending on the width of the sampling point spread function (SPSF) and of the spectral response function (SRF), the amount of acquired information may be significantly different for two cameras – even if the specified pixel and band counts are the same. As a better indication of the amount of acquired information, the authors suggest using two new specifications in the camera specification sheet: equivalent pixel count (EPC) and equivalent band count (EBC). Both specifications are derived from an optical resolution criterion such as full width at half-maximum (FWHM) of the SPSF and SRF. With the pixel count being a universally known and intuitive concept, and FWHM being a well-established resolution criterion, EPC and EBC specifications would allow for a quick and easy comparison between cameras with significantly different degree of optical blur, pixel count, and band count. EBC and EPC are drafted to be included in the upcoming standard dedicated to hyperspectral imaging devices. The standard is currently being finalized by P4001 working group, sponsored by the IEEE Geoscience and Remote Sensing Society standards committee.
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