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Re: [css3-images] image-rendering property for contrast-preserving image upscaling

From: Robert O'Callahan <robert@ocallahan.org>
Date: Fri, 3 Dec 2010 15:34:27 +1300
Message-ID: <AANLkTin5-3ASB64CiigyFvFH0s23bJ4QVuxZkAtfSicO@mail.gmail.com>
To: "Gregg Tavares (wrk)" <gman@google.com>
Cc: "Tab Atkins Jr." <jackalmage@gmail.com>, James Robinson <jamesr@google.com>, www-style list <www-style@w3.org>, public-fx@w3.org
On Fri, Dec 3, 2010 at 3:13 PM, Gregg Tavares (wrk) <gman@google.com> wrote:

> On Thu, Dec 2, 2010 at 5:59 PM, Robert O'Callahan <robert@ocallahan.org>wrote:
>
>> On Thu, Dec 2, 2010 at 3:04 PM, Tab Atkins Jr. <jackalmage@gmail.com>wrote:
>>
>>> Gimme a name for the new value and I'll add it to Image Values.
>>>
>>
>> I think sometimes authors explicitly want nearest-neighbour (e.g. to
>> expose the pixel data of an image, perhaps in an editor), so we might want
>> to provide 'nearest-neighbor' explicitly.
>>
>> For what James described as "optimize-contrast", maybe "optimize-contrast"
>> is the best name. Or maybe "preserve-contrast".
>
>
> I agree. I don't understand "optimize-contrast"
>
> Does that mean If I have 5 pixels black,red,blue,green,white and I scale to
> 10 pixels I'll get
>
> black,black,red,redish-purple,bluish-purple,blue,blueish-green,green,white,white
> since by some definitions there is no contrast between red,green,blue so
> those would be blended
>
> Why not just say "nearest-neighbor" if that's the effect people are asking
> for?
>

For some use-cases, e.g. emulators, we want to allow scaling algorithms more
elaborate than nearest-neighbor, like the ones Tab linked to earlier.

But one option is to tell those authors to implement their own scaling
algorithms in WebGL.

Rob
-- 
"Now the Bereans were of more noble character than the Thessalonians, for
they received the message with great eagerness and examined the Scriptures
every day to see if what Paul said was true." [Acts 17:11]
Received on Friday, 3 December 2010 02:36:28 GMT

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