Re: Color Format Extension

Chris Lilley <[email protected]> Tue, 9 Jan 2018 11:59:35 +0200
Newsgroups	gmane.comp.graphics.png.general
Message-ID	<[email protected]>
This is a multi-part message in MIME format.
--===============2806683996159916934==
Content-Type: multipart/alternative;
 boundary="------------0E025595DBFAEDC62EC025A4"
Content-Language: en-US

This is a multi-part message in MIME format.
--------------0E025595DBFAEDC62EC025A4
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit


On 09-Jan-18 07:37, Marcus Johnson wrote:
> Can we extend the PNG spec to support RGGB and RGGBA color formats?

What are RGGB and RGGBA used for?


>
> I was thinking the RGGB color format could be represented in the iHDR 
> chunk as 1 and RGGBA as 5 to fill out the unused values, or it could 
> be set to a completely different range for compatibility with badly 
> implemented software, I honestly don't have much of an opinion either way.
>
> for RGGB I don't think we'd need to extend the palette or any other 
> fancy features, just being able to store 4/5 channel images would be 
> great that way we could stop using camera specific formats and be able 
> to use PNG for lossless interchange.
>
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>
> _______________________________________________
> png-mng-misc mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/png-mng-misc

-- 
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture & Technology Team, Core Web & Media


--------------0E025595DBFAEDC62EC025A4
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 7bit

<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 09-Jan-18 07:37, Marcus Johnson
      wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAFWGNQUkeDJupSRUGLW81n5R8PdAw8mfFqbPTLU81jLgisSmGA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org">
      <div dir="ltr">
        <div class="gmail_default" style="font-size:large">Can we extend
          the PNG spec to support RGGB and RGGBA color formats?</div>
      </div>
    </blockquote>
    <p>What are RGGB and RGGBA used for?</p>
    <p><br>
    </p>
    <blockquote type="cite"
cite="mid:CAFWGNQUkeDJupSRUGLW81n5R8PdAw8mfFqbPTLU81jLgisSmGA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org">
      <div dir="ltr">
        <div class="gmail_default" style="font-size:large"><br>
        </div>
        <div class="gmail_default" style="font-size:large">I was
          thinking the RGGB color format could be represented in the
          iHDR chunk as 1 and RGGBA as 5 to fill out the unused values,
          or it could be set to a completely different range for
          compatibility with badly implemented software, I honestly
          don't have much of an opinion either way.</div>
        <div class="gmail_default" style="font-size:large"><br>
        </div>
        <div class="gmail_default" style="font-size:large">for RGGB I
          don't think we'd need to extend the palette or any other fancy
          features, just being able to store 4/5 channel images would be
          great that way we could stop using camera specific formats and
          be able to use PNG for lossless interchange.</div>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <pre class="moz-quote-pre" wrap="">------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! <a class="moz-txt-link-freetext" href="http://sdm.link/slashdot">http://sdm.link/slashdot</a></pre>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <pre class="moz-quote-pre" wrap="">_______________________________________________
png-mng-misc mailing list
<a class="moz-txt-link-abbreviated" href="mailto:[email protected]">[email protected]</a>
<a class="moz-txt-link-freetext" href="https://lists.sourceforge.net/lists/listinfo/png-mng-misc">https://lists.sourceforge.net/lists/listinfo/png-mng-misc</a>
</pre>
    </blockquote>
    <pre class="moz-signature" cols="72">-- 
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture &amp; Technology Team, Core Web &amp; Media</pre>
  </body>
</html>

--------------0E025595DBFAEDC62EC025A4--


--===============2806683996159916934==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
--===============2806683996159916934==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
png-mng-misc mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/png-mng-misc

--===============2806683996159916934==--