Jeremy S. De Bonet :
Reconstructing Rectangular Polyhedra
Hand-Drawn Wireframe Sketches
Because machine vision is an extremely difficult problem,
there is only so much that one can hope to solve with a single
problem. Therefore, to make this a tractable problem, some degree of
human assistance is necessary in making it possible for the system to
successfully recover the desired object(s).
- The gain must be manually set to ensure that all lines have
been recovered. Uniform illumination of the drawing is
necessary for this.
- The minimum line length threshold must also be manually set
to minimize finding spurious and fragmented lines.
- Spurious and fragmented lines are acceptable, however,
missing lines will cause the system to fail.
- Drawings must be reasonably thick dark lines on a brighter
- Input drawings must be approximately orthographic
projections of rectangular polyhedra in which lines which
indicate displacements in depth are oriented at 45 degrees.
- The drawing must be aligned with the camera when the image
- All input drawings must be COMPLETE wireframe sketches.
This means that every vertex is the junction of three
lines, one of each orientation.
But even with these limitations, the system is still very robust.
Return to Sketch Reconstruction Page.