Bonjour,
@lylejk
It’s hard to beat Gimp’s ‘sparkles’ filter…
@afre
Here is a commented example and the result
:o)
# normalize the colors between 128 and 255 to obtain lighter colors
-n[-1] 128,255
# get a 'gray' image with a richer gray
-to_pseudogray[-1] 5,1,8
# add blur for richer rendering with the 'isophotes' command
-blur[-1] 2
# to obtain contours according to the luminosite with a transparent background
-isophotes[-1] 6
# create a new image with 4 channels to the dimensions of the current image
{w},{h},1,4
# n loops or n = (width + height) /1.5
-repeat {{{w}+{h}}/1.5} # delete points
# draw a transparent line from the middle of image with a random length
-line[-2] 50%,50%,{u(100)}%,{u(100)}%,1,0,0,0,0
-done
# loops
-repeat {{{w}+{h}}/2} # points on outlines
# draw a white line with a random length
-line[-1] {u(100)}%,{u(100)}%,{u(100)}%,{u(100)}%,1,255,255,255,255
-done
# loops
-repeat {{{w}+{h}}/5} # points outside the outlines
# put white dots randomly on the image
-point {u(100)}%,{u(100)}%,0,1,255,255,255,255
-done
# 'and' between the 2 images [-1,-2] to obtain a single resulting image
-and[-1,-2]
# 'circular dilation' by 3 pixels
-dilate_circ[-1] 3
