Simple Vignette Correction

From wikipedia: In photography and optics, vignetting is a reduction of an image’s brightness or saturation toward the periphery compared to the image center.

When presenting a collection of images as a mosaic, the vignetting in the imagery can cause visual discontinuities at the image borders. Here I present a simple strategy to model and correct the vignette in a collection of images.

Step 1: Compute the pixel-wise average for a set of images

I start by creating 2d numpy array of float32 type with the same dimension as our camera. Each [u, v] position in the numpy array is …
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DJI Phantom 4 Pro camera vs. Sony A6000

Recently I flew a DJI Phantom 4 Pro v2 head to head with an in-house (U of MN AEM UAS Lab) developed fixed wing UAS. This comparison isn’t entirely apples to apples, but maybe someone will find it useful.

DJI is the king of the hill for small UAS aerial surveys. Once you figure out the apps and a few basic things, operating one of these is pretty much click and fly and makes aerial survey work about as easy as it can be. Some quick details of our system:

  • Camera horizontal field of view: about 67 degrees.
  • 20 Megapixel

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