[OpenJDK 2D-Dev] Missing colour profiles

[Alexey Ushakov]

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. 

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)

Best Regards,
Alexey
> So, where should I send these profiles?
>
> Andrew.
>
>
>   
>> Andrew Haley wrote:
>>     
>>> Andrew Haley wrote:
>>>       
>>>> Just a heads-up: I'm working on Bug 6523403, Need to provide lcms
>>>> library with PYCC and LINEAR_RGB OS ICC profiles.  I'm also looking
>>>> at the causes of Bug 6523402, Some quality problems with GRAY, PYCC
>>>> and CIEXYZ color spaces with lcms library
>>>>
>>>> I have created a LINEAR_RGB profile using the same primaries as the
>>>> lcms sRGB profile, and I have verified that it's compatible with
>>>> the Kodak-provided one in the proprietary JDK.  The PYCC profile
>>>> will take a little longer, and I've started working on that.
>>>>         
>>> Just a bit more information on my progress.  I've created a PYCC profile
>>> based on specs from Kodak, but I'm being hampered by some bugs in lcms,
>>> which at the present time can't even get the sRGB primaries exactly
>>> right.
>>>
>>> I note that this is already a known bug in OpenJDK, # 6523402.  I'm
>>> investigating.
>>>
>>> Andrew.
>>>       
>
>