[OpenJDK 2D-Dev] Missing colour profiles

[Andrew Haley]

Alexey Ushakov wrote:
> Hello Andrew,
> 
>> One final thought: we could implement some of these standard colour
>> spaces
>> by subclassing ColorSpace directly without the use of any underlying
>> colour profile.  This would be more accurate than lcms in many cases, and
>> might even be faster in some.
>>   
> There is a drawback of such approach. The color spaces implemented
> directly couldn't be effectively used  in ColorConvertOp operation with
> buffered images. Because it's impossible to link such transforms with
> icc ones (our default  sRGB color space among them). So,  the color
> transformation would end up with per-pixel color transformation of the
> whole image. Which is unacceptable slow.

Well, we could add a new case to ColorConvertOp's constructor, like

        if (cspace instanceof ICC_ColorSpace) {
...
        }
        else if (cspace instanceof DirectColorSpace) ...

> Also, there could be some problems with backward compatibility
> concerning ColorConvertOp. Because  of  ColorConvertOp(ICC_Profile[]
> profiles, RenderingHints hints) constructor. Someone could use it
> following way:
> 
> ColorConvertOp(new ICC_Profile[] 
> {((ICC_ColorSpace)ColorSpace.getInstance(ColorSpace.CS_PYCC).)getProfile()},
> null)

Ah, okay.  That's rather dubious code, but people do stuff like that.  :-)

Just idly speculating,
Andrew.