A frame that did not fit ended the job with its name, and the only way
on was Back, a smaller selection and every frame read, demosaiced and
searched for keypoints again. Each row on the page now has a box. An
unticked frame is left out and the rest are solved again from what the
first pass measured.
dr_pano::align is split for it: match_pairs does the matching and the
pairwise RANSAC once over every frame (about 5 s for twelve), and solve
takes a subset of the frames and uses only the links among them (about
0.1 s). Solving a subset by re-aligning it also moved every RANSAC seed,
which are keyed on frame position, and on the fixture set that was
enough to lose a marginal link and strand a neighbour of the frame left
out.
A frame that cannot be placed no longer stops the job either. Its row
names it and Merge stays off until it is unticked; the headless example
leaves such frames out the same way, and takes --leave-out N to try it.
Twelve real frames from the fixture set now align in 4.5 s — 4.4 s of
matching, 118 ms of bundle adjustment — where the first run took 51 s and
left the first two frames out.
The matcher computes each pair's similarity matrix once, across the
cores, with a dot product written to vectorise; both nearest-neighbour
directions read it. The frames that failed were portrait: fitted into the
landscape input they used 512 of 1024 px, and their thin overlap did not
survive at half resolution. The same weights are now exported at 768×1024
as well and the detector picks the shape by aspect. The example aligns
from embedded previews and draws the set on a cylinder; on the fixture the
sweep is 152° at a fitted 47.9 mm against the EXIF's 50, RMS 1.5 px, and
the overlaps show no ghosting.
A new crate holding the CPU half of a merge (FR-MRG-10): the grayscale
proxy with orientation, the XFeat decoder ported step for step from the
reference detectAndCompute, mutual-nearest-neighbour matching, a robust
pairwise homography with the focal length read off it, a hand-rolled
Levenberg–Marquardt bundle adjustment over every rotation and the focal,
the three output projections, and align(), which chains it all and names
the frames it could not place rather than guessing (FR-MRG-5).
Dependency-free without the xfeat feature — linalg.rs says why the dense
algebra is hand-rolled — and tested on synthetic sweeps whose answer is
known exactly. The noise test records the single-row degeneracy: one
pixel of noise is a tenth of a percent of focal, which is a uniform
stretch of the sweep, not a misalignment.
dtourolle