Error detection and correction | Structured Light 3D Scanning
Conventional Gray Codes (11 images)
Modulated Phase-shifting (162 images)
After error detection and correction
Concave lamp made of shiny brushed
Error detection using consistency
This object is challenging due to
strong, high-frequency inter-reflections. Consequently, the
depth map using our code ensemble (shown below) has a lot of
residual errors. We propose techniques for detecting
and correcting these residual
errors by acquiring more images. These techniques
significantly improve the reconstruction quality. See
comparison at the bottom of the page.
We use a consistency check among the
code ensemble for detecting errors (similar to the one used
for handling general scenes). For a pixel, if no two codes
agree, it is marked as an error pixel, as shown above. Since
no extra patterns are projected, the error detection stage
places no overhead in terms of acquisition time.
correcting using selective illumination
the subsequent iterations, the scene points which are
already decoded correctly are not illuminated. This is
achieved using an illumination mask. By progressively
reducing the number of points getting illuminated (and
hence, inter-reflections), the residual errors are reduced.
This technique is based on the work of [Xu et al, 2009].