I played a lot with Erisian globe and how to tweak it and i thinking some tweak are interesting so ..here we go
first the nice globes just derived from (the parameters of) a Erisian 3D fractal
and that i will use here
now i didn't do yet but the idea is simple, when doing a similar sphere (or anything else ) with M£D is possible get automatically also the z-buffer..cryptic name but indicate a height map and what much more relevant here something perfect to delete the image BG ( i can't say here "to make a render" because in 3D "render" mean something very different...
so i take the chances to show a few variants
and HERE THE POINT i may scale the z-buffer with same value so i may load as layermask to make the BG transparent..
opps sorry for the OT but i just found the lost black egg
ok till now is just normal asymmetric resizing (=scale width and height differently)...now what i really turned me on
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i was thinking to make a gmic filter for this for no linear resizing , but not sure if i will:
to me wrote code is a pain and if i do is usually to do something new that is not available in other way
, in this case i would just reinvent the wheel because there is already a nice utility that does well
(well..it has weird limit for file type only bmp and jpg, no png...but does works well and is free and
is called Non Linear Image Resizing Tool, i forgot where i got it but google would know...)
here what non linear resizing may do
as i say that utility doesn't load png but is possible use with the same values to the matching z-buffer, and then load the z-buffer as layermask to eliminate the BG...
just a idea i am working on
Not sure to have the skill , time and patience to make a analog Gmic filter but still that app workls fine maybe can be even called from gimp (with the robA shell script) and similar routine can give quite interesting result
Starting from high res images the output seems quite clean with no visible pixelation or artifacts...