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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">On Thursday, August 13, 2020 6:08 PM John Hudson wrote:<br>
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<p class="MsoNormal" style="margin-left:.5in">On 13082020 12:07 pm, Levantovsky, Vladimir wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I’d argue that for as long as we collectively treat this work as a single entity and discuss everything out in the open, with all interested
parties being able to freely join the discussion – the _<i>formal</i>_ agreement isn’t necessary (I am not even sure there can be such a thing with ISO having full rights to make changes to their document). We, as a community have vested interest in maintaining
the integrity of the technology, and developing it further in a way that facilitates widespread adoption and implementations.
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<p style="margin-left:.5in">Vlad, does ISO/MPEG have any kind of implementation requirement similar to, say, the W3C independent implementations requirement? Is it possible to institute one?<o:p></o:p></p>
<p style="margin-left:.5in">One of the things that has concerned me about both the OT and OFF is that they have sometimes been what I would class as speculative specifications, and have numerous features that are formally part of the format but have never been
implemented (Peter just reminded us of one). In recent years, there has been some improvement in this regard, e.g. the implementation many aspects of OT variations before the 1.8 spec was published, but so far as I am aware there is no requirement for implementation
built into the processes, and nothing like a public draft stage such as CSS has.<o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Well, while there are no formal ISO requirements related to implementations of the spec, we can institute some. MPEG has always been in favor of complementing the spec with reference
implementations so that an implementer has something else to look at if spec language isn’t 100% clear. But we also need to be mindful about the effects of these requirements – speaking about W3C work, the WOFF2.0 spec development was finalized in 2014, however,
the Recommendation has been ratified only in March 2018. The delay in final ratification was only due to work related to implementations and conformance testing. While it didn’t really hurt WOFF2 adoption, and many browser vendors don’t mind implementing the
technology specified as part of the Working Draft, ISO process is different.<o:p></o:p></span></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Also, some features may be so specific to particular scripts / layout needs that the implementation requirements would be hard to impose or enforce. Or, a feature that is optional
in nature that may be useful and nice to have but the one that is never been used – do we really want to get it out of the spec? We can definitely deprecate things that are not needed / useful.<o:p></o:p></span></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thanks,<o:p></o:p></span></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Vlad<o:p></o:p></span></p>
<pre><o:p> </o:p></pre>
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