On 6 Dez., 02:40, Tduell <[email protected]> wrote:
> I found that auto control point generators are pretty useless, as maps > have lots of common features (grid lines, symbols etc), so they find > too many spurious points. Sometimes it helps running the CPGs with higher resolution (--maxdim for autopano-sift-c) (might take a while with a high-res scan ;-) Any CPs that don't match are easily removed once the images are aligned by the ones that do. In a pickle (like, when the scans are just too large to handle) one can just make ptos to extract the strips that do overlap, CPG them with maximum scale and remap the CPs to the original images, but it's probably quicker then to manually set the CPs straight away. If there are grid lines on the maps, they are excellent for putting line control points on them. Also, it's wise to scan so that the edges of the map (which often has boundary lines as well) show up on the scan - if it's a proper topographical map, the margin would also have the data to later easily georeference the map to feed it into a GIS. line control points should help with getting the X, Y and shear parameters spot on right, which is a necessity if the extent of the total area goes beyond a few pages. I did several projects stitching sets of photographs of maps, taken freehand in rule-of-thumb mosaic fashion. It took a fair bit of fiddling getting it all to come out nicely, and line control points along grid lines were the factor which made the final difference. Having mentioned GISs, they are a certainly worth taking a look at for the task at hand; they offer facilites for overlapping (georeferenced) image data and may be more flexible dealing with map data than a panorama stitcher, which would merely produce images without being aware of the content. I'd recommend Quantum GIS - it's very powerful and takes a while to figure out, but it's well-documented and free: http://qgis.org/ My workflow is like this: digitize the maps and put back together each individual map with hugin, thereby dealing with distortions intoduced by the digitization georefernce the maps with QGIS and hold them in QGIS for synopsis take it from there (like, get tiles out) with regards Kay -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/hugin-ptx
