Closed philtomson closed 9 years ago
There's already (very limited) support for YCrCb in Images. I wasn't sure if it was interest to Color folks (it's really more about image transmission than color representation).
Do you have an example of doing a conversion to/from YCrCb in Images?
On Sat, Dec 20, 2014 at 1:03 PM, Tim Holy notifications@github.com wrote:
There's already (very limited) support for YCrCb in Images. I wasn't sure if it was interest to Color folks (it's really more about image transmission than color representation).
— Reply to this email directly or view it on GitHub https://github.com/JuliaLang/Color.jl/issues/74#issuecomment-67749632.
Check the code in src/colortypes.jl
@timholy: thanks. I was thinking this was a Color.jl issue, but in reality you're taking care of it in Images.
Well, perhaps it would be better here, but I was worried that it wasn't a "real" colorspace and might infringe on the core mission of Color, which is good colorimetry. One of the color experts here might comment, though---I'm happy to move any/all pieces of Images/src/colortypes.jl over to Color, if desired.
I think adding the YCbCr color spaces, or even other video-related color spaces to Color is fine. We already have stuff for generating palettes, which isn’t exactly pure colorimetry either. I would say adding more color spaces does not counteract correct colorimetry.
Sounds good, I'll migrate it over.
Just to give you the whole perspective, Images/src/colortypes also includes several other color types/features, most of which are designed to work with images where the raw data is stored in a different internal format than expected by Color:
AlphaColor
type where the alpha
channel comes first in the immutable (in contrast with AlphaColorValue
where it comes last; if we decide to have both, perhaps AlphaColorValue
should be renamed ColorAlpha
)AbstractRGB
types:
BGR
with a reversed storage order compared to RGB
RGB1
and RGB4
, immutables with 4 elements (one of which is a dummy) encoding RGB values. In RGB1, the dummy is first; in RGB4, the dummy is last. OSX in particular seems to like to work with 4-byte colors, which work efficiently with OpenGLYIQ
HSI
Gray
and GrayAlpha
for monochromeWant all of this? Some of it? None of it?
Is YCrCb equivilent to LAB or LUV or is it completely different? I'm working on translating an image processing algorithm which used YCrCb to Julia.