Json API Transisition Time for segments

Hi there,
i have a problem with my json api Call… i would like to fade in/ fade our when i set the LEDs… Is this possible? This Code works:

{“on”:true,“seg”:{“i”:[0,67,[255,0,0]]}}

But when i Add a Transition it makes no changes:

{“on”:true,“transition”:25,“seg”:{“i”:[0,67,[255,0,0]]}}

is it possible to add this? Or any other way to get a fade in / out in wled?
Fade in or out via the api is not possible, this will crash my system…

TIA