[FFmpeg-user] Generating a displacement map

[Moritz Barsnick]

Hi Evert,

On Wed, Jul 05, 2017 at 13:31:15 +0200, Evert Vorster wrote:
> Using ffmpeg, hugin, and some scripting, each image is un-distorted
> according to it's lens characteristics, and stitched together to make an
> equirectangular frame.
[...]
> Rather than figure out the location of each pixel every time, it would be
> much more efficient to just use a displacement map and move the pixels.

Do have a look at the "displace" filter. The examples show how to
describe the displacement with an equation/formula:

https://ffmpeg.org/ffmpeg-filters.html#displace

> Actually generating such a map might be a bit of a trick.
> Is there any ideas from the community on how to generate and use such a map?

If you can describe it mathematically, you may be able to use ffmpeg's
expression system for the formula. Otherwise you would create two
"images" which contain this displacement data, and feed them as looped
inputs. The actual description of the map is probably up to you (and
hugin or the lens database).

Cheers,
Moritz

> Isometrix Acquistion Superchief

Lovely title you have there. :-D