4 ms·
Transformations like these have wide applicability. Performing optics in software so to speak, is more flexible and cheaper than grinding lenses and building sp
by JoeAltmaier 4y ago
Transformations like these have wide applicability. Performing optics in software so to speak, is more flexible and cheaper than grinding lenses and building special cameras.
I was charged once, with transforming images for projection onto a sphere through special lenses. I didn't know the lens transform, the manufacturer kept that secret. I did know that the intensity across the spherical surface was of uniform brightness - the manufacturer boasted about this. With that bound I could guess the transform, as each pixel of the source image would have to illuminate an equal surface area of sphere once projected.
The manufacturer advertised a service to do this transform on your image, but they wanted $10K for each run! Once I presented my insights and a little math, they capitulated and did it at cost. I never got to write my projection software in the end.
- myth2018 4y agoHey, that's a nice case study! Could you give me some pointers on where I could start studying about the math involved? Are those topics usually covered by good books on computer graphics?
- jeffreygoesto 4y agoI loved "Multiple View Geometry" by Hartley & Zisserman, but also "Computer Vision" by Rick Szelisky is pretty comprehensible and covers a lot of (pre-ML) stuff.
- triggercut 4y agoMy goto, which has literally saved me weeks of banging my head against a wall, is: Schneider, P.J., Eberly, D.H., 2003. Geometric tools for computer graphics, Morgan Kaufmann Publishers indispensable
- daniel_reetz 4y agoSounds like a classic f-theta lens design. I'm sure you were right about your transform, but it's also possible to equalize illumination by other means, like apodizing filters.