  This paper provides the first thorough documentation of a high quality
digitization process applied to an early printed book from the incunabulum
period (1450-1500). The entire OCR related workflow including preprocessing,
layout analysis and text recognition is illustrated in detail using the example
of 'Der Heiligen Leben', printed in Nuremberg in 1488. For each step the
required time expenditure was recorded. The character recognition yielded
excellent results both on character (97.57%) and word (92.19%) level.
Furthermore, a comparison of a highly automated (LAREX) and a manual (Aletheia)
method for layout analysis was performed. By considerably automating the
segmentation the required human effort was reduced significantly from over 100
hours to less than six hours, resulting in only a slight drop in OCR accuracy.
Realistic estimates for the human effort necessary for full text extraction
from incunabula can be derived from this study. The printed pages of the
complete work together with the OCR result is available online ready to be
inspected and downloaded.
