This is in fact an important question. I havn't looked at the code good enough to be able to give an answer.
I suggest looking at first at the code of the geometrical optimizer (fastPTOptimizer or libpano13). Probably most of the code with the math concerning the CP coordinates is the original code of Prof. Helmut Dersch. Somewhere the pixel coordinates together with the hfov will be converted into angles on the unit sphere or maybe normed coordinates on some "image plane". This could be a good place to look. Maybe I find the time and will look myself. If some code in Hugin++ is not consistent with it, it should be adjusted. After all, it wouldn't make sense to estimate the CP position with sub-pixel accuracy (in the fine tuning) if at the same time there are systematic errors of 0.5 pixels due to inconsistencies in the code. [email protected] schrieb am Sonntag, 15. Mai 2022 um 12:34:54 UTC+2: > Control points coordinates allow fractions of a pixel (1/3 pixel at a time > when moving via arrow keys. Even finer detail for "fine tuning" results). > > What is the precise meaning of the coordinate relative to the pixel? > > Imagine each pixel as a square in a very magnified image. I would expect > best behavior if that pixel's integer coordinates represented the center of > that pixel. But maybe some code would be simpler if the pixel's exact > coordinates represented the top left corner of that pixel (its coordinates > plus 0.5,0.5 would be its center). > > I'm pretty sure various parts of of the hugin code are inconsistent with > each other regarding that decision (following neither of the above rules > and differently from other sections of the hugin code). > > I'm working on some enhancements to hugin++, that I can only code > correctly if I know the precise answer to this question. So I looked for > it in the current code and experimentally in the current behavior and found > contradictions. I'd like to know which parts are following the intended > behavior, vs which are subtle bugs. > -- A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ --- You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/1fdfd361-58de-417e-b79f-675fb04394c5n%40googlegroups.com.
