JPEG Lossless does not support non-rgb colorspaces
Posted: Sun Dec 24, 2006 10:59 pm
I think I noticed this as far back as B2, actually, and it totally slipped my mind. Any colorspace other than true RGB isn't transformed correctly from JLS, instead it just treats all panes as RGB. Here are a few examples:
original PNG
JLS RGB
JLS (R-=G, B-=G) (now known as YCoCg)
JLS (R-=G, B-=(R+G)/2)
JLS YCbCr (Jpeg color)
JLS YCbCr (Jpeg2k color)
It doesn't overly bother me, I only use the format as mid-term storage when I don't want to store some enormous psd for six months. But I thought you'd like to know so you could keep it in mind in the future.
V 1.90 B6
original PNG
JLS RGB
JLS (R-=G, B-=G) (now known as YCoCg)
JLS (R-=G, B-=(R+G)/2)
JLS YCbCr (Jpeg color)
JLS YCbCr (Jpeg2k color)
It doesn't overly bother me, I only use the format as mid-term storage when I don't want to store some enormous psd for six months. But I thought you'd like to know so you could keep it in mind in the future.
V 1.90 B6