fade_diamond
Arguments:
- 0<=_start<=100,0<=_end<=100
Description:
Create diamond fading from selected images.
Default values:
start=80 and end=90.
Example of use:
$ gmic
image.jpg testimage2d {w},{h} +fade_diamond 80,85

Command:
image.jpg testimage2d {w},{h} +fade_diamond 80,85

Command:
image.jpg testimage2d {w},{h} +fade_diamond 80,85

Command:
image.jpg testimage2d {w},{h} +fade_diamond 80,85