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Hello. As a long time lurker here, I'd like to share my latest project with the DIY Drones community.

In working with orthophoto generation from UAV imagery using the current crop of still-photo stitching based programs, I have found the process to be complicated and frustrating.

I thought there must be a simpler way, and it occurred to me that pushbroom scanning from video is another way to make nice orthophoto-like images. This works without going through the complex 3D reconstruction process that the expensive stitching programs are using.

I have created a program called Aeriality Video Pushbroom. It is simple, it is available now, and it is very low cost. You can find it at www.aeriality.io

What it does is take an aerial video like this:

And it creates a constant-perspective strip-map image like the one one the left.

Even though it is a simpler process than the 3D reconstruction based stitching, pushbroom scanning has some advantages in comparison.

• Its much faster. Get results in minutes instead of hours.
• It continues to work well where stitching often fails to find key points, such as over farm fields, bare soil, or water.
• When stitching has problems you get holes, gaps, and out of place or highly distorted images. With Aeriality Video Pushbroom errors in a good image are limited to small localized distortions.
• Allows simpler hardware, flight planning and operations. You don't have to worry about image overlap or shutter triggering. And post-flight you only need to work with a single video file instead of hundreds of still photos.
• It runs locally on your machine. No need to wait to upload lots of large files to a cloud service, and no worries about the privacy or security of your data.
• Very efficient for long surveys. You can summarize a video into to an output image faster than real time viewing of the video. Potential applications in surveying power lines, pipelines, fences, towers, agriculture, and search and rescue.

Also, with this software I am testing a theory of business, sales, and pricing, that people will pay a reasonable price for something if it creates value for them. I would prefer to make money only if you are getting value from my work. In fact, I want to create more value for you than I capture.

With that in mind, I made Video Pushbroom with individual $3 licenses that can be used for each single video you want to process (only verifying its cryptographic hash against our server). And if you like the software and find that you are using it a whole lot, or want to use it without an internet connection to our server, there is an unlimited use license that covers you as well. To make it fair, if you ever want to upgrade to the unlimited license, the price of any single uses you have purchased will be deducted from the unlimited price. At the current pricing, that means if Aeriality Video Pushbroom is so useful to you that you have used it 33 times, you can keep using the software for free after that.

This being the internet, I realize that some people like to tear things down. So I thought I would pre-respond (prespond?) to some potential criticisms:

This doesn't actually do any alignment of the pushbroom scan, aren't you aware of all of the work that does this? Photogrammetry is a hard problem and you are not even trying to solve it. This sucks and is not as good as X.

Yes, I am aware of that (clearly, since I'm attacking my own straw-man here). The software will get better and add more features, though with a priority on simplicity. I am aware of the research literature and common techniques used by the computer vision, photogrammetry, and remote sensing communities, and have an advanced background in those fields. I hope that people will find the current software useful as-is, so I am releasing it for sale now (and not selling a dream on Kickstarter).

Thanks for reading. I hope you try my software, www.aeriality.io

thanks
-Taylor

Edit: The original strip map got cut off in the post. A full version is below