Seems much easier than when I had to do this manually onto Google Earth.
Photogrammetry on commercial flights (2021)
21–30 of 41 posts
Re: Photogrammetry on commercial flights (2021)
#22This is not photogrammetry as the word is usually understood these days. Photogrammetry usually means constructing a 3D model out of a number of 2D photos from lots of different angles, although there are broader definitions as well [1]. This is just skewing a photo you took out the window to overlay it on a map. From the title, I was expecting this to be something about constant super-hi-res photography attached to…
Correct, the technique is called orthorectification.
Re: Photogrammetry on commercial flights (2021)
#23This is very cool! How feasible would it be to take a video instead of a photo, then using landmark detection and a stitching algorithm such as SIFT to cover a larger surveying area?
A better solution would be to use a program that does what most people think of when they hear the word photogrammetry these days, 3D reconstruction from multiple images, and then make an orthorectified image from that. OpenDroneMap can do that for example. https://www.opendronemap.org/webodm/
An areal photo that's orthrorectified with ground images as a secondary source would provide better normals. Of course we'd also use differential GNSS base-point targets to stitch the images together. It's difficult to get consistent color temps, exposure, etc with multiple ground images shot at various times throughout the day.
Re: Photogrammetry on commercial flights (2021)
#24Earlier quoted context omitted.
The internet makes that problematical. Does 'distribution' include 'share on facebook'? I've been wondering for some time, how far do national laws about data sharing matter any more?
Yes, any distribution including online. Personally I think it's a bit anachronistic to ban distribution of photos now when it's so easy to take and distribute them, not to mention all kinds of commercial services with free aerial and street view photos. People do get prosecuted for it still, so it very much matters. https://www.lantmateriet.se/en/dissemination-permit/
I share such photos, and never got arrested. But I'm not Swedish.
If you're Swedish and share such photos in the US, is it a crime?
Where is the 'internet' at? Certainly not in any particular nation.
Thus my confusion.
Re: Photogrammetry on commercial flights (2021)
#25> But other than taking a few photos of holiday mementos and lens-flaring sunsets, what’s the point? OT, but for me the point is not having my body absolutely panic from experiencing all kinds of rotation and sudden lateral displacement without anything happening visually. Honestly, I have no idea how people fly anywhere else, I wouldn’t be able to. The speeds and forces experienced even on a calm commercial flight a…
What you experience on a regular flight is a complete non-issue compared to what you can experience in a car, in an amusement park, or in VR.
And if you remove the direct comparisons, then people do things like say, war, parachute jumping, or underwater welding that are way more extreme.
Really like everything it's just the matter of getting used to it. As a kid flying used to be amazingly exciting. Then I got a job that involved flying twice a week and it very quickly got routine.
The weird forces also don't last very long at all. For the vast majority of the flight is just sitting in a chair, and feels exactly like that.
Re: Photogrammetry on commercial flights (2021)
#26This is very cool! How feasible would it be to take a video instead of a photo, then using landmark detection and a stitching algorithm such as SIFT to cover a larger surveying area?
You can think of a video as a set of images taken from the same camera from different perspectives. So, you can assume as if they're different cameras (with the added bonus that the camera intrisincs remain the same), and apply "multi camera" techniques. I'm assuming you "move" the camera for parallax and what not.
With this, you can retrieve depth information by correlating the difference in position of easily identifiable points, and recreate the scene as a mesh.
This is basically the basis of photogrammetry as I know it. AI solutions may help at various stages to speed up the process too.
Re: Photogrammetry on commercial flights (2021)
#27Earlier quoted context omitted.
Yes, any distribution including online. Personally I think it's a bit anachronistic to ban distribution of photos now when it's so easy to take and distribute them, not to mention all kinds of commercial services with free aerial and street view photos. People do get prosecuted for it still, so it very much matters. https://www.lantmateriet.se/en/dissemination-permit/
I share such photos, and never got arrested. But I'm not Swedish. If you're Swedish and share such photos in the US, is it a crime? Where is the 'internet' at? Certainly not in any particular nation. Thus my confusion.
law !== enforcement
Re: Photogrammetry on commercial flights (2021)
#28pshh, Big Globe has been using photogrammetry for it's "window" displays for decades.
/s
Re: Photogrammetry on commercial flights (2021)
#29To explain the underwhelmed response I guess most people were expecting ’google maps quality’ 3d models. Which is not an unreasonable expectation, given an aerial platform such as a drone converting photos to 3d models of large areas is commoditized. Just dump photos to an application such as Agisoft Metashape or Luma, wait a bit and you can get something like this for example: https://skfb.ly/6DvVP
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Re: Photogrammetry on commercial flights (2021)
#30Despite the author's criticisms, it seems like there's lots of opportunity for UAV-generated open source imagery, but I can't really find an active community for sharing it. Open Aerial Mapp[1] seems like a good start, but doesn't seem to be particularly active. Seems like we could use a "Mapillary[2] but from Above" type of project - only one that doesn't end up getting acquired by Facebook. [1] https://openaerialma…
https://github.com/OpenDroneMap/ODM You take a drone, point the camera mostly down (a narrow angle, not straight down), take photos of land, with some overlap, preferably from different angles, load the software, and it creates an ortophoto, 3d model, height map, all georeferenced
ODM is a way to preprocess data before sending it to OAM, but it does not itself provide a sharing platform.
One barrier for OAM seems to be that it requires the image to be already orthorectified. To be more like Mapillary you'd need a service that takes georefed pictures and does its own processing.
In the case of airplane window photos where georef is not going to be good enough, you might need existing photos to correlate with -- ADS-B track combined with time can help provide a starting guess, but not much else.