<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On 14 Sep 2009, at 11:57, John Robert Peterson wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Part of the idea of this project was to kick start thinking about this sort of thing.<br><br>The ideal situation for me would be if we could have some automated tool on a sever somewhere receiving images from users, and automatically rectifying them.<br> <br>This sounds imposable, but I believe that with a very small amount of user help it could work:<br>Images can be automatically pinned together in overlaps (and high res images can be pinned onto wide area images) using tools similar to those in Panorama Tools / <span class="il">hugin (this searches for notable points in the image data, and matches them between images)</span>;<br> searching the images for road markings (and/or cars) and matching these to the gps traces already uploaded would give a reliable enough way to add real world control points;<br>if a concept of altitude is added, automatic control points between images appearing on top of skyscrapers would not be too damaging;<br> approximate terrain relief for most of the planet is already known, this can be tied into the above to help;<br> manually adding control points would be done by displaying already rectified images next to a map, with the user adding pins to useful points;<br>images with no rectification data at all would be added using a push pin system similar to that used on <a href="http://warper.geothings.net/">http://warper.geothings.net/</a><br> <br>the above is a pipe dream at the moment, but has the potential to revolutionise how we do things in my opinion.<br><br>Any further ideas on this?<br><br>The images of stratford were taken mostly angled, with a few almost vertical. we spiraled around the town and I took images out the downward facing window, it seemed to work pretty well (if the results are a little chaotic)<br> <br>mapping from these images is the million dollar question -- the raw images are going up online at <a href="http://www.flickr.com/photos/thingomy/collections/72157622345143470/">http://www.flickr.com/photos/thingomy/collections/72157622345143470/</a> and are fine for visual reference while mapping, but rectifying them is a more tricky issue.<br></blockquote><div><br></div>I get the impression that rectification gets a lot harder as the angle gets more slight and it is clear to me that a camera pointing straight down would be the most useful device going forward. The time of day is also important to avoid long shadows. I am pleased that this project is creating some useful discussion which we should continue to see what we can extract from these images and what we can learn going forward.</div><div><br></div><div>Tools to process images and to host rectified images seem to be pretty crucial to take full advantage of all this.</div><div><br></div><div>Fyi, I have added comments to some images to say what it is of, the bearing the image was taken at, and the appropriate link to OSM.</div><div><br></div><div><br></div><div><br></div><div>Regards,</div><div><br></div><div><br></div><div>Peter</div><div><br></div><div><br><blockquote type="cite"> <br>JR<br><br><br><div class="gmail_quote">2009/9/14 Tristan Thomas <span dir="ltr"><<a href="mailto:tristan.thomas@wikinewsie.org">tristan.thomas@wikinewsie.org</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div><br>Many of the photos taken above Stratford upon Avon seem to be taken at an angle-how do people find them for mapping from?</div> <div><br> </div> <div class="gmail_quote">2009/9/14 Chris Hill <span dir="ltr"><<a href="mailto:osm@raggedred.net" target="_blank">osm@raggedred.net</a>></span><div><div></div><div class="h5"><br> <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0px 0px 0px 0.8ex; padding-left: 1ex;">I used to hold a pilot's licence and I did some work photographing archaeological sites. Photos taken pointing sideways are much harder to work with than photos pointing straight down. Any kind of rectification adds unwanted artifacts. I used to make high bank angle turns (60' bank angle) over the feature I wanted to photograph which made it very easy to photograph.<br> <br>I was trying to photograph a small area in detail, so circling over the feature helped. I was also using film (before widespread hi-res digital), so there was a limited stock of film but the resulting image was the equivalent of about 25mp. To reduce parallax I used a telephoto lens.<br> <br>It gives a very interesting overview, but it's not a patch on surveying on the ground where you have access.<br><br>Cheers, Chris<br><br>Tristan Thomas wrote:<br> <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0px 0px 0px 0.8ex; padding-left: 1ex;"> <div>I would be very interested to hear what people think of this effort. I'm currently studying to be a pilot & I know that many people who do fly routinely take aerial pictures of the landscape below, especially of towns etc. I know most of them would be more than happy to allow their photos to be used of OSM. If we could find a way to upload them somewhere, then I'm sure we could dramatically increase the aerial photography we have without having to pay to hire the planes or get it sponsored. I could just upload them all under one Flickr account for OSMers to look through & do some tracing if they wish, but it doesn't seem the most efficient way to do it?<br> Thoughts?<br></div>------------------------------------------------------------------------<br><br>_______________________________________________<br>Talk-GB mailing list<br><a href="mailto:Talk-GB@openstreetmap.org" target="_blank">Talk-GB@openstreetmap.org</a><br> <a href="http://lists.openstreetmap.org/listinfo/talk-gb" target="_blank">http://lists.openstreetmap.org/listinfo/talk-gb</a><br> <br></blockquote><br><br></blockquote></div></div></div><br> <br>_______________________________________________<br> Talk-GB mailing list<br> <a href="mailto:Talk-GB@openstreetmap.org">Talk-GB@openstreetmap.org</a><br> <a href="http://lists.openstreetmap.org/listinfo/talk-gb" target="_blank">http://lists.openstreetmap.org/listinfo/talk-gb</a><br> <br></blockquote></div><br> _______________________________________________<br>Talk-GB mailing list<br><a href="mailto:Talk-GB@openstreetmap.org">Talk-GB@openstreetmap.org</a><br>http://lists.openstreetmap.org/listinfo/talk-gb<br></blockquote></div><br></body></html>