Acquired aerial photography (1:5000 to 1:60 000 scale).
Performed aerotriangulation of photography, geo-referencing all photogrammetric controls to true ground coordinates.
Collected vector digital data using analogue plotters (Wild A10 - A8 - B8S). Vector data were three dimensional (x,y,z) and geo-referenced to UTM coordinates. The output format was DXF.
Performed cursory checks of digital data (removal of pseudo nodes, creation of polygons, etc.).
Built lines and points then copied attribute information from the ACODE and XCODE tables into the arc and point attribute tables (AAT and PAT). Dropped five attribute fields from the resulting attribute tables.
Selected arcs representing buildings based on the dxf-layer attribute. Put the arcs for each building category to respective ArcInfo coverages.
Built building polygons, created error files if dangles or intersections were present, then cleaned coverages with fuzzy and dangle tolerances of 0.0001.
Manually edited coverages to eliminate dangles.
Joined all building layers into one coverage, cleaned with tolerances of 0.01, and checked for label errors. Performed manual edits to correct label errors.
Appended mapsheet building footprint coverages into a Manitoba-wide coverage and cleaned with fuzzy and dangle tolerances of 0.01. Unsplit arcs based on the dxf-layer attribute code. Performed edits to ensure good edgematching. Eliminated sliver polygons created by overlapping polygons along mapsheet boundaries. Checked for and corrected label errors.
Visually checked polygons with an area of less than 14 square-meters. If polygons represented overlapping buildings, performed manual edits to separate building footprints.