Figure 3: PPAc for multiple colour-channel 3D pinpointing using one computer-mouse click.
Image shown: a confocal image of a Drosophila late embryo where cells are labelled using fluorophores with different colours. R: a shooting ray from the observer to the on-screen 2D mouse-click locus. p: the final 3D location estimated by finding the one with the maximal intensity among candidates p1*, p2* and p3*, which are detected for all colour channels independently. For each colour channel, the progressive mean-shift method is used to narrow down the search range Rik (in this case i=1, 2, 3, and the iteration indicator k=1, 2, …) along the shooting ray until convergence.
