@Edent If you enjoy the nerdery and want optimal results, try calibrating it. Take some images of chessboards at different angles and feed into OpenCV or similar.

I'm guessing they do this in the factory and store the calibration in the firmware, to account for manufacturing variation.

OK! Getting somewhere!

This is the ffmpeg filter which will convert fisheye to equirectangular.

`-vf "v360=input=dfisheye:output=equirect:ih_fov=189:iv_fov=189"`

But there's a slight issue with overlap. If you look closely at the above image, there's some cut-off around the sides.

I wonder if splitting the frames in two, re-paging them, and then combining would make it look better?

@Edent
Matt Parker @standupmaths made a video donkeys years ago messing about with spherical cameras. https://www.youtube.com/watch?v=x0gRcRd_rHs

Link to Henry's github: https://github.com/henryseg/spherical_image_editing

@Edent I think you can do it in ffmpeg with the v360 filter. Something like this, but you'll need to tweak the parameters a bit:

https://video.stackexchange.com/questions/37100/how-do-i-use-ffmpeg-to-stitch-220-degree-fisheyes-into-a-360-equirectangular-vid

@Edent Speculation: Might take some experimentation to get the right parameters, but ffmpeg's v360 filter will probably do what you want: https://ayosec.github.io/ffmpeg-filters-docs/7.1/Filters/Video/v360.html