[hugin-ptx] Re: How can I locate a control point in remapped images?
On Apr 9, 9:31 am, "Terry Duell" wrote: > pano_trafo is definitely returning coords from the point in the stitched > pano, not the coords in the remapped image. Ooops, my mistake. The 'Create cropped images by default' was set. With that switch not set, I now get remapped images and coordinates that make sense. Not looked at Preferences for a while, and had forgotten about that setting. I'll also plead that the it doesn't make it clear what images are being created cropped by default. So, problem solved. Thanks for the help. Cheers, Terry -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: enfuse for tonemapping of a single RAW
I don't know if this is related, but the luxrender project recently added film response curves intended to emulate various cameras during tonemapping Here are some details (read down the topic) http://www.luxrender.net/forum/viewtopic.php?f=12&t=5456 And a link to the CRF files: http://www.luxrender.net/release/crf/ -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: Hugin Experience
Ah well! I have "Ø" symbol printed on the side of my Canon EOS 350, I was told this was the NPP point... as you pointed out, likely not. http://www.dpreview.com/reviews/CanonEOS350D/Images/allroundview.jpg Top right view, above the strap slit. Anyone know what this point marks? -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
On Sat, 09 Apr 2011 09:05:12 +1000, Terry Duell wrote: Hullo Bruno, When I tried pano_trafo the x coords being returned were way outside the range of those of each of the remapped images. Maybe I'm having another bad day and misunderstood what I was seeing, I'll try again. pano_trafo is definitely returning coords from the point in the stitched pano, not the coords in the remapped image. I have a work-around for this issue for the small number of cases I'm trying, but it is a bit cumbersome, and it would be nice to get the coords directly. What I have done is find control points, then choose one and get the coords in each image. I then load the original images into gimp and at the point location paint a small white cross hair. Then load the altered images back into hugin, align and save the remapped images, each of which now have the small white cross hair. As I said, cumbersome or perhaps more correctly, tedious, but I can now use the altered originals and remapped images for a number of experiments. I shouldn't have to do too often...well not at my current rate of progress! Cheers, -- Regards, Terry Duell -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
Hullo Bruno, On Sat, 09 Apr 2011 08:58:05 +1000, Bruno Postle wrote: The panorama coordinates should be the same as the remapped images coordinates, or will be unless you have cropped TIFF output set. I'm not using cropped TIFF output...or didn't think I was. When I tried pano_trafo the x coords being returned were way outside the range of those of each of the remapped images. Maybe I'm having another bad day and misunderstood what I was seeing, I'll try again. Cheers, -- Regards, Terry Duell -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
On Sat 09-Apr-2011 at 08:44 +1000, Terry Duell wrote: On Sat, 09 Apr 2011 08:38:48 +1000, Bruno Postle wrote: There is a pano_trafo -r option that should reverse the transformation. Not sure how that would help. I can get control point coords from each image of a pair, then optimise and save remapped images. I want to get the coords of those same points in the remapped images. It looks to me as though pano_trafo translates between the original images and the stitched pano (and wicki-werka), certainly looks that way by the numbers it has been producing. The panorama coordinates should be the same as the remapped images coordinates, or will be unless you have cropped TIFF output set. If you want to keep using cropped TIFF output, you can read the offsets with tiffinfo and subtract them (you have to convert from inches to pixels which is a bit of an annoyance). -- Bruno -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
Hullo Bruno, On Sat, 09 Apr 2011 08:38:48 +1000, Bruno Postle wrote: Wasn't pano_trafo made for this? I have tried pano_trafo and it puts out pano coords, not the coords of the remapped image. There is a pano_trafo -r option that should reverse the transformation. Not sure how that would help. I can get control point coords from each image of a pair, then optimise and save remapped images. I want to get the coords of those same points in the remapped images. It looks to me as though pano_trafo translates between the original images and the stitched pano (and wicki-werka), certainly looks that way by the numbers it has been producing. Cheers, -- Regards, Terry Duell -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
On Sat 09-Apr-2011 at 08:30 +1000, Terry Duell wrote: On Fri, 08 Apr 2011 22:48:48 +1000, Erik Krause wrote: Am 08.04.2011 03:18, schrieb Tduell: I would like to be able to locate a control point in each of a pair of remapped images. Is there a way of extracting the coordinates from Hugin? Wasn't pano_trafo made for this? I have tried pano_trafo and it puts out pano coords, not the coords of the remapped image. There is a pano_trafo -r option that should reverse the transformation. -- Bruno -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: How can I locate a control point in remapped images?
On Fri, 08 Apr 2011 22:48:48 +1000, Erik Krause wrote: Am 08.04.2011 03:18, schrieb Tduell: I would like to be able to locate a control point in each of a pair of remapped images. Is there a way of extracting the coordinates from Hugin? Wasn't pano_trafo made for this? I have tried pano_trafo and it puts out pano coords, not the coords of the remapped image. Is there a way to derive the remapped image coords from the pano coords? Cheers, -- Regards, Terry Duell -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Re: GSoC Enblend seam-finding proposal
Hi, I managed to set up my workspace today, with the instructions on the page it was a breeze. I test-built both Enblend and Hugin, no problems. I'm going to familiarize myself with the code tomorrow and produce a patch after that. Some family business going on this weekend, so it might take a while longer than expected, but I'll make sure to get it done. On Apr 8, 10:56 am, cspiel wrote: > When you are able to build Enblend and Enfuse on > your box and preferable the documentation, too, > IMHO the first step would be to modularize the > seam-line generation. This is, make the > seam-line optimizers pluggable components; > define an interface which which they interact with > the rest of Enblend. We could build on this idea and make the core seam-finding algorithms (the current one and the upcoming graph-cut so far, possibly more in the future) modules as well, so that the user can select his favorite one. Optimizers would either be global, or exclusive to a given core algorithm. Thanks for the comments and suggestions everyone! Best regards, Mikolaj -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: enfuse for tonemapping of a single RAW
On Fri 08-Apr-2011 at 20:21 +0200, Pablo d'Angelo wrote: Am 07.04.2011 20:20, schrieb Bruno Postle: If I knew what a standard response curve looked like as EMoR parameters then I would suggest that Hugin used it as a default. Currently we use 0,0,0,0,0 which doesn't correspond to any real camera. Thats something like the "mean" response curve of all cameras/films that where used to derive the EMoR model, so it should be a good start. Ok, I must have got the wrong idea about this. I remember Joost saying that ptgui uses a different set of baseline EMoR parameters, but I could have misheard this completely. -- Bruno -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Adding Thin Plate Spline algorithm to bend images
My name is Lukasz Maliszewski. I am a last year Informatics student from the Technical University of Gdansk in Poland, Faculty of Electronics, Telecommunications and Informatics. My GsoC proposal: My idea is to implenet Thin Plate spline. Thin Plate Spline lets to deform image in an unlimited way. We describe how we want to bend an image by defining set of control points and their destination positions. The algorithm bends an image in a way that the control points are moved to the desired positions. The big advantage of the algorithm is that the Image after transformation looks very natural. Example can be seen here: http://dl.dropbox.com/u/13127408/koala.jpg I think that such functionality would be useful for panorama application. It is quite often that the component images are deformed and control points do not overlaps. Thin plate spline could bend image in the most natural way so that the control points would overlap. I have submitted this proposal on GSoC site. I am aware that my proposition is incomplete and it is very late for GSoC proposal but let me know if such functionality is desired by You. Best Regards, Lukasz Maliszewski Computer Science, Technical University of Gdansk in Poland. -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Re: Hugin Experience
Am 08.04.2011 19:46, schrieb Yclept Nemo: I aligned the camera's sensor plane with the panoramic head's center of rotation It is very unlikely the entrance pupil of your lens coincides with the sensor plane. The no-parallax-point (NPP) is located at the center of the entrance pupil. If you used the sensor plane to rotate around you probably have misplaced the NPP by 60mm or more. This could produce parallax errors, even at larger distances. You can use the formulas on http://wiki.panotools.org/Parallax to estimate how large they would be (calculate for the shortest distance). -- Erik Krause http://www.erik-krause.de -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: Hugin Experience
> Important: Horizontal, vertical, and straight lines are evaluated on their > output projection. Hm, so that's why my mercator projection + straight line @ ~25° was throwing off the alignment... so this means that: equirectangular: vertical lines only, plus horizon line Does this also apply to cylindrical, mercator, miller, architectural ? (i'm using mercator) That explains the GSoC idea of moving "line" control points to the preview windows. > Yes, it is useful. If you want to level your panorama using the horizon it is > best to have horizontal CPs approximately 45° apart. Only problem I see with horizon control lines, is that unlike straight lines they only specify two points. Horizontal CPs are more effective further apart, however all the intermediate images are not straightened: they can be wavy/squiggly. -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Re: enfuse for tonemapping of a single RAW
Hi Bruno, Am 07.04.2011 20:20, schrieb Bruno Postle: On Wed 06-Apr-2011 at 23:54 -0700, Jeffrey Martin wrote: If I knew what a standard response curve looked like as EMoR parameters then I would suggest that Hugin used it as a default. Currently we use 0,0,0,0,0 which doesn't correspond to any real camera. Thats something like the "mean" response curve of all cameras/films that where used to derive the EMoR model, so it should be a good start. ciao Pablo -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: Hugin Experience
On 2011-04-08 10:35 AM, paul womack wrote: whats the difference between vertical control point lines and horizontal control point lines? -> http://wiki.panotools.org/Horizontal_control_points -> http://wiki.panotools.org/Vertical_control_points -> http://wiki.panotools.org/Panotools_internals#Line_control_points If I have 5 images A B C D E that I wish to line up, am I better making ? A-B, B-C, C-D, D-E or A-B, A-C, A-D, A-E or A-C, B-C, C-D, D-E pairs? BugBear "Line" control points are evaluated (optimized) by comparing the a line drawn by the first two points and the distance all other points are from that line. So I always place the first two points at the ends of the line. The rest of the points for that line makes no difference how they are added. So if I had multiple straight lines going though multiple images I would probably do. A-E, B-D, C-C If does not matter how the "line" points are added to B, C, D Important: Horizontal, vertical, and straight lines are evaluated on their output projection. -- Jim Watters http://photocreations.ca -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: Hugin Experience
thanks for the suggestions: Just to be clear, the problem is not in my control points. I have 24 stacks with 50% overlap, per overlap I've manually placed 20-40 high-correlation well-distributed accurate control points. After optimizing my average error is 0.4, rms error 0.6, max error 1.7. The problem is that despite such a high accuracy, hugin produces a panorama with so many and so noticeable artifacts. Furthermore, I doubt the problem can be attributed to accuracy: I aligned the camera's sensor plane with the panoramic head's center of rotation, and pretty much all objects are more than 35 feet distant. In any case, your suggestion was really very good, am I'm running a test stitch now. My zoom lens has slots around the barrel demarcating focal lengths, so therefore it was relatively easy to set a focal length of 28mm. The barrel is stiff enough to prevent the focal length from changing. Furthermore, the camera provides the focal length in the exif image data and it turns out this number is consistent across all images; this is what hugin uses to calculate FOV. Nonetheless I adopted the philosophy of "distort each individual image as non-physically as needed to minimize control-point distances". Even though I was pretty sure all lens parameters where correct (v) and consistent (a,b,c,d,e) across all images, I nonetheless unlinked and optimized v,a,b,c,d,e for each image: After optimizing my average error is 0.1, rms error 0.2 and maximum error distance 0.93. Like I said, I'm still stitching but hopefully this gets rid of the glitches once-and-for-all. I'm also going to attempt another test stitch with a similar strategy on the version with the straight lines. -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Top 10 Websites To Learn Online
Top 10 Websites To Improve and Learn Math, Science or Any Other Subject Online The importance of Internet in getting knowledge, particularly using its Web is a well-recognized fact. A wealth of resources and techniques are now available which serve as a source both for exciting examples of new teaching practices, as well as easily accessible methods for adoption into various formats of teaching and learning. Internet technology allow teachers and students keep up with their minds. It let them try their ideas as soon as they come up with them. In addition to that, web-based learning can be a flexible and cost-effective alternative to classroom learning. Today, a list of websites have been gathered which can be beneficial both for students and teachers to learn online. Check out full article over here:- http://bit.ly/EduIdia -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Re: Hugin Experience
Erik Krause wrote: Am 08.04.2011 10:43, schrieb Yclept Nemo: By the way, whats the difference between vertical control point lines and horizontal control point lines? -> http://wiki.panotools.org/Horizontal_control_points -> http://wiki.panotools.org/Vertical_control_points -> http://wiki.panotools.org/Panotools_internals#Line_control_points > And is it useful to have these lines across different images Yes, it is useful. If you want to level your panorama using the horizon it is best to have horizontal CPs approximately 45° apart. With regards to "line" control points. If I have 5 images A B C D E that I wish to line up, am I better making A-B, B-C, C-D, D-E or A-B, A-C, A-D, A-E or A-C, B-C, C-D, D-E pairs? BugBear -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Re: How can I locate a control point in remapped images?
Am 08.04.2011 03:18, schrieb Tduell: I would like to be able to locate a control point in each of a pair of remapped images. Is there a way of extracting the coordinates from Hugin? Wasn't pano_trafo made for this? -- Erik Krause http://www.erik-krause.de -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] strahov gigapixel
yes, I really enjoyed it. its really impressive work done. Jeffery what are technical details of equipment (camera, lens etc) used for it? How you calculated exposure for such a huge mosaic. On Tue, Mar 29, 2011 at 7:34 PM, Jeffrey Martin <360cit...@gmail.com> wrote: > Hi Everybody, > > Just thought you might enjoy this > > http://www.360cities.net/gigapixel/strahov-library.html > > It wasn't made with Hugin though. Maybe when I can get cpfind to reduce > images to a specified pixel size ;-))) > > seriously though, I would like to make one of the next ones using hugin, to > give hugin some nice publicity! :-) > > cheers, > Jeffrey > -- > 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 hugin-ptx@googlegroups.com > To unsubscribe from this group, send email to > hugin-ptx+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/hugin-ptx > -- *Emaad* www.flickr.com/emaad -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
[hugin-ptx] Re: Hugin Experience
Am 08.04.2011 10:43, schrieb Yclept Nemo: By the way, whats the difference between vertical control point lines and horizontal control point lines? -> http://wiki.panotools.org/Horizontal_control_points -> http://wiki.panotools.org/Vertical_control_points -> http://wiki.panotools.org/Panotools_internals#Line_control_points > And is it useful to have these lines across different images Yes, it is useful. If you want to level your panorama using the horizon it is best to have horizontal CPs approximately 45° apart. -- Erik Krause http://www.erik-krause.de -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Hugin Experience
On 8 April 2011 09:38, Yclept Nemo wrote: > > Yes I did manage to borrow a panoramic head; even without out, since > the lightpost is about 50-75 feet distance I doubt parallax would > cause any problems. It should be straight-forward to calculate the maximum parallax error (in pixels) based on an estimated upper bound in the change of position of the no-perspective point and the angular distance between pixels at 28mm. But yes: I would have thought that that would be sufficient, even if the control points were quite a lot further away and the pano head wasn't exactly calibrated (i.e., not rotating precisely around the NPP). > I use a cheap Canon EFS 18-55mm lens which I calibrated specifically for 28mm I think I would be worried about not being able to re-set the lens to exactly the focal length it was calibrated at. On my (relatively cheap) lenses, even if I were to tape the zoom ring to the body so it couldn't rotate between calibration and shooting (or equivalently make sure it is hard against the 18mm stop), there is enough play in the mechanism that I would not expect to get good results without optimizing (unlinked) v. I don't generally find it necessary to unlink a, b, and c, though, although I do include these in the optimisation. Aside: I admit that I'm not really sure I see the point of being able to save/load lens parameters when I can just include these in the optimisation. Is there any advantage, other than perhaps saving some CPU time? I would think think that, except for prime lenses, any reduction in optimisation time would be at the risk of the lens not actually being at the same focal length that was used for the calibration. > Anyway, is it possible to produce a perfectly aligned 360 degree > panorama? I've been trying really hard - many different strategies - > and am unable to get rid of artifacts. I have shot and aligned only one full 360-degree panorama, and it was from handheld, and despite this I did not have much trouble getting things to align sufficiently for there to be no visibile artifacts. Here is the strategy I used, which I've used before on several other less-than-360 panoramas with good success: - Shoot three bracketed exposures of each of 21 stacks (9 stacks around the equator) (from the middle of a large, cobbled public square). - Load 63 images into Hugin. - In the image list and in the preview, select the middle-exposed image from each stack (#1, 4, 7, ... 61) and use cpfind to create control points. - Optimize (y, p, r) to start with, with "Only use control points between image selected in preview window" ticked. - Manual control point editing: fine-tune all; delete all control points in sky and most on the cobblestones in the foreground (large parallax errors due to hand-holding); delete a few more down an alley (again, parallax errors); add quite a few manually between overlapping images where cpfind did not do a good job (probably about 25cps on each of a dozen different overlap pairs). - Optimize (y, p, r, v (unlinked), a, b, c (linked), d, e (unlinked)) and continue to examine and adjust or delete poorly-aligned control points until errors are relatively small (average error = 0.85, maximum error < 3.8). At this point almost all the control points are on the fronts of buildings around the square. - Do test stitch to check alignment. No problems - even with cobbles in foreground enblend has done a good job hiding misalignments. - Now, select first stack (images 0, 1 & 2) and use Align_image_stack linear to create control points. Repeat for each additional image stack. - Create control points manually for images where Align_image_stack did not do a good job (usually due to my having allowed the camera to roll slightly between exposure, which usually results in control points being clustered around centre of image with few at edges). - Select all images in preview window, and optimize the same parameters as before (y, p, r, v (unlinked), a, b, c (linked), d, e (unlinked)) to bring everything into alignment. - Stitch. Add masks to deal with moving people, birds, etc. Repeat. There are probably several ways I could improve this process (e.g.: I'm not sure it's necessary or particularly useful to select images in groups of three when using Align_image_stack). In general, I find the strategy of having only the middle-range exposure from each stack linked to adjacent images, with lots of auto-generated control points between the images in each stack provides good results while keeping the total number of control points to a reasonable value (~8k, for the panorama described above). Christopher -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr.
[hugin-ptx] Re: GSoC Enblend seam-finding proposal
Mikolaj - Great to learn you are keen on improving Enblend! On Apr 7, 4:33 pm, Rosomack wrote: > I'm interested in improving the seam-finding algorithm in Enblend (or > more specifically - writing a new one). I found the topic on one > of the ideas pages, hope it's still an open issue. Seam optimization still is an issue in Enblend-4.0 and the improvement of it would be highly welcomed. I have read your proposal and it looks perfectly sound to me as you offer both knowledge of C-like languages and -- more importantly -- expertise in the field of image blending. > Please suggest a good area of code for me to patch. OK, I'm wearing my Enblend/Enfuse "Chief Housekeeper Hat" here, not the "GSOC Mentor Hat" (because there is none in my wardrobe). When you are able to build Enblend and Enfuse on your box and preferable the documentation, too, IMHO the first step would be to modularize the seam-line generation. This is, make the seam-line optimizers pluggable components; define an interface which which they interact with the rest of Enblend. With this interface the current "1d optimizer" will simply become one of several optimizers. We need that for backwards compatibility anyhow. After that modularization step you can experiment with as many different optimizers as you want to (even in parallel). Furthermore, other developers could jump in with their own seam-line optimizer ideas. And in the end, the users can select the optimizer which fits their needs from the command-line. Best, Chris -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Hugin Experience
By the way, whats the difference between vertical control point lines and horizontal control point lines? And is it useful to have these lines across different images (ie horizontal lines would take care of pitch while CPs would take care of roll) Also the documentation says straight control point lines require more than two points, does that mean more than two points per image: ["A B B A","C D D C"] or more than two points overall: ["A A","B B"] -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Hugin Experience
On Thu, Apr 7, 2011 at 8:13 PM, Christopher Allen wrote: > On Apr 7, 2011 6:15 PM, "Yclept Nemo" wrote: >> >> RAW images are in linear color space so hugin would >> not have to reverse-calculate the response curve applied by >> ufraw/dcraw. > > Is that generally true? I don't know much about raw processing (or indeed > about image sensor electrical behaviour) , but I wouldn't have guessed that > light input -> raw pixel values would be necessarily or even typically > linear. I'm pretty sure it's accurate: http://www.luminous-landscape.com/tutorials/expose-right.shtml The gist: 2x light = 2x voltage = 2x pixel intensity. Since human vision is logarithmic-ish, perceiving a greater range of luminance across darker values, a centred exposure fails to utilize the upper-half of the camera's sensor. Anyway my point is that since RAW images represent actually the image recorded by the sensor, reading directly from these files makes moot the need to apply a camera response curve or optimize for white-balance. >> And I have an additional question: >> >> I have a lightpost running vertically straight through the center >> section of an overlapping area between two images. There are 40 >> control points scattered across these two images, and I am sure all >> control points are accurate. Furthermore each control point can be >> optimized to an error of less than 1px. So I am stumped as to why, in >> the stitched output, the lightpost is misaligned by at least 20px. >> Does anyone have any suggestions? > > Well, if it were my panorama it would be because of parallax from > hand-holding the camera, but I'm assuming that you're using a calibrated > panorama head. > > (And a much better lens: my 18-200mm Nikkor has enough variation in FoV due > to aperture and focus changes there I can't get a good fit when processing > image-stacked panoramas without optimizing (unlinked) v too.) Yes I did manage to borrow a panoramic head; even without out, since the lightpost is about 50-75 feet distance I doubt parallax would cause any problems. Interestingly enough I found that since the panoramic head is so large vertically and lacking a clamp, at certain angles it must have acted as sail and subtly rotated - a few of my brackets stacks are misaligned. I use a cheap Canon EFS 18-55mm lens which I calibrated specifically for 28mm Anyway, is it possible to produce a perfectly aligned 360 degree panorama? I've been trying really hard - many different strategies - and am unable to get rid of artifacts. I find it interesting how radical and under-realized a job the blender does - I wish hugin would allow a visualization of the seams (graph paths) used by enblend: Different strategies: 1] Let hugin/CPFind pick points. Many many points. Many don't actually correspond to identical features despite high correlation. Images are drastically unaligned, yet enblend does a very good job. Very few artifacts (2-3) with high error (10-50px perceived) 2] Let hugin/CPFind pick points, then manually subtract. Never finished. Too many points to filter, plus optimization strategy wants to get rid of my points (all my points -> 100+px error distance) 2] Pick points myself. 20-40 per stack. Precise + high correlations. Images are very well aligned, yet many minor artifacts produced. 10-20 artifacts with error of (2-10px) 3] Pick Points + Use straight lines. Perhaps I don't know how to use straight lines. In any case, whereas normal points average error of <1px, line CPs average error of 10-20px. 20-30 artifacts with error of 2-10px, visually errors are less noticeable than in previous strategy. 4] Pick Points + Use vertical lines. Work in Progress. Anyone have tips? This is really frustrating. -- 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 hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
