Re: Call for informal discussion: APNG

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If we do new APNG we could do anything we want, but I don't think global=20
interlacing is good idea.

It break too much compatibility and significantly increase difference=20
with current APNG (and so complexity of decoder).

I think best way for "new APNG" (which definitely should get new name)=20
is be superset of current APNG (with different chunk names), so at least=20
some subset of NewAPNG could be converted to APNG files without decoding=20
image data, but just with chunk repacking.


20.09.2017 20:18, Soni L. =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> If we do get a new APNG, can we get full image interlacing?
>
> As you know, in APNG, you can do interlacing to make each frame=20
> visible faster at a lower resolution, but EACH FRAME ONLY. The idea=20
> with full interlacing is that you'd interlace IDAT and fdAT, such that=20
> you can quickly load the whole APNG animation (at a lower resolution),=20
> and slowly get it up to high-res by loading the following chunks.
>
> On 2017-09-20 12:30 PM, Pavel Zlatovratskii wrote:
>>
>> I don't think approval of APNG could be any use for now. It was=20
>> important in 2007 to motivate browsers (and other software) support=20
>> it. But today it is already have pretty wide support as you describe,=20
>> so I see no reason to not left it as Mozilla's "side-standard".
>>
>> May be it's possible to design some new animation PNG based on APNG=20
>> and make it standard. Like SPDY and HTTP/2: Google design and spread=20
>> SPDY, but SDPY is now left as SPDY, not became HTTP2.0 nor was=20
>> approved by IETF HTTP WG.
>>
>> There is also a little problem with official APNG same as Mozilla=20
>> APNG: current decoders may not able to handle approved aCTL chunk as=20
>> it is supposed to handle private acTL chunk. So without any benefit=20
>> for aCTL it may be never spread.
>>
>> 15.09.2017 2:09, Chris Lilley =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
>>> My reason for re-opening discussion is the "implementation and=20
>>> testing" part. APNG has since become widespread. Compared to=20
>>> animated GIF, it offers 24bit (and 48bit!) colors rather than 256,=20
>>> and full transparency rather than binary opacity.
>>>
>>> Regardless of what we may think about the reduced capabilities=20
>>> relative to MNG, or the advisability of re-using an image type for=20
>>> animations, this is the current state of the world and it seems=20
>>> sub-optimal to me that the PNG specification and extensions=20
>>> documents continue to not reflect this. I would like therefore to=20
>>> kick off informal discussion, then a formal discussion period and=20
>>> (re)vote.
>>>
>>> APNG continues to be supported in Mozilla Firefox (and other apps=20
>>> using the Gecko rendering engine), starting from version 3, June 2008=
.
>>>
>>> APNG is supported by Safari (and other apps using the WebKit=20
>>> rendering engine) since version 8, October 2014.
>>>
>>> In addition, native apps on MacOS X and iOS use native support for=20
>>> APNG, since iOS 10 and OS X Yosemite, October 2014.
>>>
>>> APNG is now supported by Google Chrome (and other apps using the=20
>>> Blink rendering engine, such as Opera and Samsung Internet),=20
>>> starting from version 59, June 2017.
>>>
>>> Microsoft Edge does not support APNG, but MS Edge Devs stated that=20
>>> this is "under review". Meanwhile, APNG displays in Edge as the=20
>>> first frame, which is the expected fallback behavior.
>>>
>>> A starter document is attached to facilitate discussion.
>>>
>>> --=20
>>> Chris Lilley
>>> @svgeesus
>>> Technical Director @ W3C
>>> W3C Strategy Team, Core Web Design
>>> W3C Architecture & Technology Team, Core Web & Media
>>>
>>>
>>> ---------------------------------------------------------------------=
---------
>>> 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
>>
>> --=20
>> Have a nice DOS.
>>
>> Pavel Zlatovratskiiscondo-JGs/[email protected];[email protected]
>>
>>
>> ----------------------------------------------------------------------=
--------
>> 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
>
>
>
> -----------------------------------------------------------------------=
-------
> 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

--=20
Have a nice DOS.

Pavel Zlatovratskii scondo-JGs/[email protected]; [email protected]


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    <p>If we do new APNG we could do anything we want, but I don't think
      global interlacing is good idea.</p>
    <p>It break too much compatibility and significantly increase
      difference with current APNG (and so complexity of decoder).</p>
    <p>I think best way for "new APNG" (which definitely should get new
      name) is be superset of current APNG (with different chunk names),
      so at least some subset of NewAPNG could be converted to APNG
      files without decoding image data, but just with chunk repacking.<b=
r>
    </p>
    =C2=A0<br>
    <div class=3D"moz-cite-prefix">20.09.2017 20:18, Soni L. =D0=BF=D0=B8=
=D1=88=D0=B5=D1=82:<br>
    </div>
    <blockquote
      cite=3D"mid:d5597239-0e12-d71e-a6c1-d311caf70b11-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
      type=3D"cite">
      <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DU=
TF-8">
      If we do get a new APNG, can we get full image interlacing?<br>
      <br>
      As you know, in APNG, you can do interlacing to make each frame
      visible faster at a lower resolution, but EACH FRAME ONLY. The
      idea with full interlacing is that you'd interlace IDAT and fdAT,
      such that you can quickly load the whole APNG animation (at a
      lower resolution), and slowly get it up to high-res by loading the
      following chunks.<br>
      <br>
      <div class=3D"moz-cite-prefix">On 2017-09-20 12:30 PM, Pavel
        Zlatovratskii wrote:<br>
      </div>
      <blockquote type=3D"cite"
        cite=3D"mid:ab199da1-004a-5f1c-843a-4f3dda06b755-o+MxOtu4lMCHXe+LvDLADg@public.gmane.org">
        <meta content=3D"text/html; charset=3DUTF-8"
          http-equiv=3D"Content-Type">
        <p>I don't think approval of APNG could be any use for now. It
          was important in 2007 to motivate browsers (and other
          software) support it. But today it is already have pretty wide
          support as you describe, so I see no reason to not left it as
          Mozilla's "side-standard". <br>
        </p>
        <p>May be it's possible to design some new animation PNG based
          on APNG and make it standard. Like SPDY and HTTP/2: Google
          design and spread SPDY, but SDPY is now left as SPDY, not
          became HTTP2.0 nor was approved by IETF HTTP WG.<br>
        </p>
        <p>There is also a little problem with official APNG same as
          Mozilla APNG: current decoders may not able to handle approved
          aCTL chunk as it is supposed to handle private acTL chunk. So
          without any benefit for aCTL it may be never spread.<br>
        </p>
        <div class=3D"moz-cite-prefix">15.09.2017 2:09, Chris Lilley
          =D0=BF=D0=B8=D1=88=D0=B5=D1=82:<br>
        </div>
        <blockquote
          cite=3D"mid:fa3adedb-5d2c-c892-4ae4-ef928270e542-Pl0VvzL1eo4@public.gmane.org"
          type=3D"cite">
          <meta http-equiv=3D"content-type" content=3D"text/html;
            charset=3DUTF-8">
          My reason for re-opening discussion is the "implementation and
          testing" part. APNG has since become widespread. Compared to
          animated GIF, it offers 24bit (and 48bit!) colors rather than
          256, and full transparency rather than binary opacity.<br>
          <p>Regardless of what we may think about the reduced
            capabilities relative to MNG, or the advisability of
            re-using an image type for animations, this is the current
            state of the world and it seems sub-optimal to me that the
            PNG specification and extensions documents continue to not
            reflect this. I would like therefore to kick off informal
            discussion, then a formal discussion period and (re)vote.<br>
          </p>
          <p>APNG continues to be supported in Mozilla Firefox (and
            other apps using the Gecko rendering engine), starting from
            version 3, June 2008.</p>
          <p>APNG is supported by Safari (and other apps using the
            WebKit rendering engine) since version 8, October 2014.<br>
          </p>
          <p>In addition, native apps on MacOS X and iOS use native
            support for APNG, since iOS 10 and OS X Yosemite, October
            2014.</p>
          <p>APNG is now supported by Google Chrome (and other apps
            using the Blink rendering engine, such as Opera and Samsung
            Internet), starting from version 59, June 2017.</p>
          <p>Microsoft Edge does not support APNG, but MS Edge Devs
            stated that this is "under review". Meanwhile, APNG displays
            in Edge as the first frame, which is the expected fallback
            behavior.</p>
          <p>A starter document is attached to facilitate discussion.<br>
          </p>
          <pre class=3D"moz-signature" cols=3D"72">--=20
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture &amp; Technology Team, Core Web &amp; Media</pre>
          <br>
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        <pre class=3D"moz-signature" cols=3D"72">--=20
Have a nice DOS.

Pavel Zlatovratskii <a class=3D"moz-txt-link-abbreviated" href=3D"mailto:=
scondo-JGs/[email protected]" moz-do-not-send=3D"true">scondo-JGs/[email protected]</a>; <a class=3D"=
moz-txt-link-abbreviated" href=3D"mailto:[email protected]" moz-do-not-sen=
d=3D"true">[email protected]</a>
</pre>
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----------------------------
Check out the vibrant tech community on one of the world's most
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</pre>
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    <pre class=3D"moz-signature" cols=3D"72">--=20
Have a nice DOS.

Pavel Zlatovratskii <a class=3D"moz-txt-link-abbreviated" href=3D"mailto:=
scondo-JGs/[email protected]">scondo-JGs/[email protected]</a>; <a class=3D"moz-txt-link-abbreviated"=
 href=3D"mailto:[email protected]">[email protected]</a>
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