C. The Steps
- KAKAP starting from the provision of basic large-scale map. These maps was derived by high resolution imagery that is owned by the Ministry of Agrarian and Spatial Planning / National Land Agency (ATR / BPN). The imagery of quick bird captured in 2008 that covering the whole Gresik except Bawean island.
- The rectification was done by using 71 ground control points (GCP) and then tested their accuracy by using 39 independent control points (ICP). Measurement of GCP / ICP was done using GPS geodetic measuring instrument with the method of positioning relative to the reference point of order three base point of Ministry ATR / BPN. This base map rectification results with accuracy of 2.51 meters.
- With the basic map the entire registered parcels mapped (graphical mapping index / GIM). Then the unregistered parcels were mapped by delineation and identified by unique numbers that called Identification Number, Nomor Identifikasi Bidang (NIB).
The mapped parcel have 4 degrees of accuracy:
- Red line: validated
- Yellow line: registered
- Green line: surveyed
- Blue line: delineated