Spectral Library Generation for Hyperspectral Archaeological Validation Kelly Canham a , William Middleton b , David Messinger a , and Nina Raqueno a a Center for Imaging Science, Rochester Institute of Technology, 54 Lomb Memorial Dr., Rochester, NY, 14623 USA; b Department of Sociology and Anthropology, Rochester Institute of Technology, 18 Lomb Memorial Drive, Rochester, NY, 14623 USA. ABSTRACT Fractional abundance maps have been produced from Hyperion hyperspectral data over Oaxaca, Mexico, by applying a new spatially adaptive spectral unmixing algorithm. The goal of this research is to produce land-use maps for aiding archaeologists studying the Zapotec civilization. However, to correlate the fractional abundance maps generated from the HSI image processing, a relationship between the known materials located in Oaxaca, Mexico, and the spectral profiles of these materials must be established. A field campaign during December 2011, (the dry season in Oaxaca) took place for the explicit task of obtaining spectral profiles of the most common materials found in the region. Ground-truth information was collected for three Oaxaca valleys (Tlacolula, Yanhuitlan, and Ycuitla). Common materials and associated regions were recorded and material samples were collected at many of these locations. Laboratory reflectance spectral profiles of the collected material samples are measured after the field campaign using a FieldSpec Pro. Wavelength ranges of the FieldSpec Pro spanned 350-2500nm matching that of the hyperspectral imagery collected from the Hyperion sensor on board the EO-1 satellite. GIS maps of the three valleys in Oaxaca, Mexico, are used to identify where these samples were collected and correspond to the laboratory measured material samples. The spectral library entries obtained correspond to bare soils, senescent agricultural vegetation, senescent natural vegetation, and terra cotta tile. Keywords: Hyperspectral, ground-truth, and spectral profiles 1. INTRODUCTION A recent study of the ancient Zapotec statehood from Oaxaca, Mexico, focuses on how the people impacted their envi- ronment and how the environment impacted the state. Determining the different materials and land-uses of the region is a critical step of this research. Spectral unmixing has been performed on hyperspectral Hyperion imagery of Oaxaca to help automatically identify the number of different materials and the spectral profiles of the different materials. 1, 2 All this analysis, however, does not identify what these materials are. In December 2011 ground truth data was collected to help identify some of the spectrally unmixed materials. Ground truth data was collected from three valleys in Oaxaca: Tlacolula, Yanhuitlan, and Ycuitla Valleys. Tlacolula is one of the valleys that forms the Central Oaxaca Valley, where the present day state capital city (Oaxaca Cuidad de Juarez) is located. Both Yanhuitlan and Ycuitla are part of the larger Nochixtlan Valley and are found approximately 70km north-west of Oaxaca Cuidad de Juarez. The social and political environment of Mexico and the custom regulations between Mexico and the USA were all challenges that impacted the outcome of this field campaign. However, field notes, digital photos, and sample materials were collected from 56 points of interest within the three valleys. The reflectance spectra of the collected material samples were later measured in a laboratory using an Analytical Spectral Device FieldSpec Pro and constant light source. The results of the ground-truth data were compiled into Geographical Information System (GIS) truth maps and a material spectral library. The GIS truth maps of the three valleys and the entries to the material spectral library are presented here. Further author information: (Send correspondence to Kelly Canham.) Kelly Canham.: E-mail: kac7669@rit.edu, Telephone: +1 585 319 3939 David Messinger.: E-mail: messinger@cis.rit.com, Telephone: +1 585 475 4538 Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XVIII, edited by Sylvia S. Shen, Paul E. Lewis, Proc. of SPIE Vol. 8390, 839012 · © 2012 SPIE CCC code: 0277-786X/12/$18 · doi: 10.1117/12.918676 Proc. of SPIE Vol. 8390 839012-1 Downloaded from SPIE Digital Library on 25 Jun 2012 to 129.21.58.44. Terms of Use: http://spiedl.org/terms