I have seen some things in the FAQ section of DJI.
Frankly, I find it a bit confusing, especially the last section. (BOLD)
Does the Phantom 4 RTK camera digital signal processor (DSP) support distortion correction?
No, you can enable the distortion correction in the camera but the images will be less precise compared to distortion elimination in post-processing software.
How is the Phantom 4 RTK camera calibrated?
Each Phantom 4 RTK camera goes through a calibration process that measures the distortions of the lens, and records the corresponding undistort parameters in XMP DewarpData. When the “distortion correction” is switched off, the original image with distortion will be generated. When the “distortion correction” is switched on, the parameters used to eliminate distortion is not the parameters calibrated, but the design parameters of the camera. When eliminating the distortions, it is not done pixel by pixel.
So the camera internally does NOT use the data stored in the file for distortion correction?