Line scan camera image processing
I use my line scan camera to take cool pictures of trains and other stuff.
But there’s a lot that goes into properly processing the images.
1 Principle of operation
The way it works is that the camera has a single column of pixels (or in this case, two columns), that scans at a super high speed. The camera is stationary, but as a train moves past it, it gets scanned.
This is essentially also how a photo finish camera works.
Since the background is static, it gets repeated for every column of the image, giving it its distinctive striped look.
FIGURE 6 Principle of operation of a line scan camera, which produces an image where the horizontal dimension is time rather than space. source: cmglee on Wikimedia Commons Download Original
Line scan cameras are very suitable for capturing trains, since I can capture the full length of the train with minimal perspective distortion. This is super nice for train nerds who want to make models of the trains. Also, as you keep the camera running, you can get incredibly high resolution photos that span over 100,000 pixels wide.
By the way, film photo finish cameras and strip cameras behave almost the same as line scan cameras but with one subtle distinction, which is that you have to pull the film across a strip that’s somewhat wider than a single column of pixels. This is because film is less sensitive than modern digital image sensors. However, you’ll need to know the approximate speed of the subject and pull the film across at roughly the right speed.
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