[ptx] automatch: another attempt at semi-automatic panorama stitching

[JD Smith]

On Sun, 2004-01-04 at 12:42, Ed Halley wrote:
> 
> On Sun, 2004-01-04 at 14:29, Bruno Postle wrote:
> > So I've written a proof-of-concept tool that implements my "angular
> > distance" technique of automatically detecting control points:
> >
> > It outputs a hugin compatible script file:
> > 
> >     http://bugbear.blackfish.org.uk/~bruno/distance/foo.pto
> 
> So this sounds like a good candidate for a feature launched on the
> Images tab of Hugin, when it gets to that stage of implementation.  The
> user would collect the images and then push an "auto-arrange" button on
> the Images tab or the Preview panel.  Unless the images are fisheye,
> Hugin will have already gotten the HFOV and just needs to approximate
> the yaw/pitch/roll for each image.
> 
> Does the method require any knowledge of the ultimate final projection
> (equirectangular, etc.)?  In other words, does projection choice affect
> the automatic discovery and selection of match control point features?

I think not.  The mosaic used implicitly for this automated control
point matching is not a single projection, but rather a patchwork
collection of individual tangent-plane (aka rectilinear, aka gnomonic,
aka gnomic) projections.  This is a perfectly valid arrangement for
matching, but of course will not look good at all as a mosaic, hence the
need to specify a final re-projection.  For small enough fields-of-view
(of a single image), the patchwork tangent non-projection is almost
equivalent to a single tangent-plane projection centered at the
mid-point.

JD