Fig. 5

An active source (X) is projected along the view axis of the pinhole (P). By not knowing the true depth, any of some possible positions (circles) could be projected onto the image plane of P. This ambiguity cannot be resolved to correctly augment the image produced by the optical camera (C) with information from P. However, by moving C as close as possible to P (light gray), their respective projections converge. Adding a depth estimate improves the accuracy of the image augmentation further. Note the differences between the mapped projections of the image plane of C. We observe that with increasing distance these differences decrease, yielding a decaying error curve (cf. the “Error quantification” section)