  Kanzelh\"ohe Observatory for Solar and Environmental Research (KSO) of the
University of Graz (Austria) is in continuous operation since its foundation in
1943. Since the beginning its main task was the regular observation of the Sun
in full disc. In this long time span covering almost seven solar cycles, a
substantial amount of data was collected, which is made available online. In
this paper we describe the separate processing steps from data acquisition to
high level products for the different observing wavelengths. First of all we
work out in detail the quality classification, which is important for further
processing of the raw images. We show how we construct centre-to-limb variation
(CLV) profiles and how we remove large scale intensity variations produced by
the telescope optics in order to get images with uniform intensity and
contrast. Another important point is an overview of the different data products
from raw images to high contrast images with heliographic grids overlaid. As
the data products are accessible via different sources we also present how to
get information about the availability and how to obtain these data. Finally,
in an appendix, we describe in detail the information in the FITS headers, the
file naming and the data hierarchy.
