posted: March 24, 2014 | author: Aaron Lawrence
Co-written by Chris Chalmers, subject-matter expert
Woolpert was contracted to develop a comprehensive database of historical imagery collections for Hawaii and the Pacific Island Territories (American Samoa, Guam, CNMI) from existing, multi-agency inventories. Additional effort was put into working with targeted agencies to create inventories for historical image collections where none currently exist. We digitized, georeferenced and created metadata for historical images selected by NOAA from the resulting compiled inventory. All of these digital images will be available online at Digital Coast.
The historical imagery existed in a number of conditions and a number of locations. Since it would be beyond the scope of this project to inventory every singular, un-inventoried image, Woolpert inventoried these images on a per acquisition and collection basis. Every effort was made to assess each image collection as a whole for image resolution and quality (scratches, tears) and atmospheric quality (clouds, haze) as well as provide estimated geographic coverage at the USGS DOQQ level (for Hawaii) and village level for the territories. Each previously un-inventoried collection became one attributed record in the inventory based on the available information. In total we inventoried 28,870 images.
The image inventory includes the following fields:
NOAA and Woolpert sampled numerous resolutions for the scanning portion of this project. We deemed 600 dpi to be the best option for black and white images and 1,000 dpi for any color images. After identifying and prioritizing the images, we decided the Hawaii 1954 data set was complete and available for scanning. We traveled to Hawaii to ensure the images existed in as original condition as possible. These images were selected for georeferencing, and were georeferenced to a pre-existing land cover maps and satellite data sources selected by the Pacific Services Center. In addition to the Hawaii 1954 dataset, we also scanned all available Hawaii 1965 images. In total, we scanned and digitally preserved 4,313 images total.