Technical Drawing Analysis
Locating the repeated fragments, layout blocks and title areas of complex rasterized drawings.
Exploring the structure of engineering sheets through image analysis before attempting higher-level interpretation of their contents.
Recovering structure from a sheet
Before reading every symbol, identify where meaningful fragments live.
Engineering sheets combine multiple drawing views, notes, frames and a title block. The prototype treats a rasterized sheet as a spatial structure: it locates candidate regions and repeated fragments to feed more specialized recognition later.
Three analytical directions
Repeated elements
A user-selected rectangular or polygonal region can serve as a template. Correlation responses produce candidate locations; overlapping and nearby results can be filtered.
Area geometry
Image regions, separators and occupied/empty zones provide clues about page layout. This structural step helps locate the main drawing, secondary views and possible title blocks.
Implementation detail
The archive includes Python/OpenCV code using raster images, region selection and template matching. A parallel Local Binary Pattern response was explored; the preserved final-selection branch relies on template matching, so we do not describe LBP fusion as an independently validated feature.
Results are spatial hypotheses—bounding regions and match scores—not a complete recovered CAD model.
Limits and intended use
Nothing in the inspected code demonstrates general vector-PDF parsing, complete semantic reading of engineering specifications, or robust reconstruction of arbitrary CAD drawings. The implemented scope is a useful upstream stage: identifying and localizing structures on complex rasterized sheets.
Status: historical analysis prototype, 2025, with code and visual records.
Related work
These connections describe related engineering ideas, not interchangeable products.