Re: What does the line in feDisplacementMap about color-interpolation filters not applying to in mean?

Hi Robert,

This is an official response from the W3C SVG Working Group.

I have been assigned to look in to your inquiry about the 
feDisplacementMap. I will discuss this issue with the working group over 
the next few weeks and provide a resolution to your issue. Currently 
members the working (myself included) are quite busy with SVG Open 
preparation and I apologize in advance for not being able to provide a 
resolution sooner.

For your convenience the issue has been placed in our public bug 
tracker. The bug number is 4919. You can track the progress at: 
http://www.w3.org/Bugs/Public/show_bug.cgi?id=4919

Kind Regards,

Anthony Grasso

Robert Longson wrote:
> In http://www.w3.org/TR/SVG/filters.html#feDisplacementMap there is a line
> 
> The 'color-interpolation-filters'  property only applies to the in2
> source image and does not apply to the in source image.
> 
> I'm not really sure what this means.
> 
> In gecko we've implemented filters by creating an sRGB bitmap of the
> original drawing which we then apply the filters to. Each filter
> converts its input bitmap(s) to either LinearRGB or sRGB depending on
> the value of color-interpolation-filters and then processes the output
> to an output bitmap in the same colour space as its converted input.
> The final output is then converted back to sRGB if necessary for
> display.
> 
> For feDisplacement map we can convert the in2 source image before we
> work on it but what are we supposed to do with the in source image?
> 
> a) Always convert in to LinearRGB (or sRGB)
> b) Convert it based on color-interpolation rather than
> color-interpolation-filters
> c) Leave it as whatever it happens to be.
> 
> If c) then what happens if in and in2 are the same do we need two
> copies of the input surface, one for in2 which we convert based on
> color-displacement-filters and one for in which we don't. Also if in
> is the output of another filter is in whatever
> color-interpolation-filters was for that filter?
> 
> Best regards
> 
> Robert.
> 
>

Received on Thursday, 9 August 2007 05:58:20 UTC