Thanks for the advice !
I adapted your second solution and wrote an RGB image and used the three R G B
fields to put the three "bits" of my sampling so that my distance is :
It seems to be working fine and my precision went from 256 grays to over 16
millions grays, which is quite enough :)
I other have more elegant solutions to change the output format of save_file,
feel free to help ;)
Thomas
