From: Jim W. <jwa...@ph...> - 2011-01-24 14:25:37
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Can you tell by reading the exif data if the image was cropped or resized? There was an issue a little while back on the PTGui list that discussed how different Raw converters produced images on different widths. Will this cause a problem? Or will this fix this problem. Sorry don't have time right now to look it up. Jim On 2011-01-24 12:04 AM, Thomas Sharpless wrote: > Hi all > > I've just finished what I hope will be the final revision of the Wiki page > http://wiki.panotools.org/Lens_Correction_in_PanoTools > > It is now, I hope, a clear statement of how PT computes correction parameters, > why those are not portable between image formats, and what needs to be done to > make them portable. > > Bottom line, I think: > > * add the physical pixel width in microns and the fitted focal length in > mm as new 'i/o' parameters. > * compute the source fl in pixels from these if present (portable input), > from fov if not (trad input) > * provide calls to get and set pixel width in microns. If no size has > been set (trad input) get should return 0. Passing 0 to set should be > ok and mean "use input value" (0 if input is trad). > * Save params as portable when a nonzero pixel width has been posted > (portable input or app set new width). > * use 'portable' radial() parameters internally when script has portable > params. Otherwise use trad ones and convert the params on output if a > pixel width has been posted. > * for trad input and trad app only, use and save trad parameters. > > > This reduces the job of front ends to the bare minimum, of acquiring and > posting sensor specs. It requires no new behavior when the source format has > not changed -- that covers all presently valid use cases. And eliminates the > rotated source problem (provided the camera has square pixels) . > > The most important benefit, IMO, is that apps that need lens correction would > be able to use PT parameters, even if they don't use libpano. > > Best, Tom > > > > On Sun, Jan 23, 2011 at 10:03 PM, Thomas Sharpless <tks...@gm... > <mailto:tks...@gm...>> wrote: > -- Jim Watters http://photocreations.ca |