Challenge
The original master plan was a large image. Individual plots had no searchable coordinates or structured data.
Solution
We combined image processing, number recognition, geographic alignment, and manual GIS review to turn the plan into structured plot data.
Outcome
A searchable property mapping system that can support location-based listings and property applications.
Under the hood
The source was a 14,002 × 9,977 px marketing image. A staged pipeline removes the watermark, finds plots with watershed segmentation, reads plot numbers with OCR, takes sizes from the legend colours, then vectorises the result and fits it to GPS reference points. QGIS is the review desk, with bookmarks for 70 blocks. Every plot number records where it came from, and the pipeline has 400+ automated tests.
Accuracy
The mapping is not survey-grade. Plot positions are aligned to reference points and reviewed by hand, which is right for search and listings, not for legal boundaries.