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<p class="MsoNormal"><span style="font-size:11.5pt;font-family:"Arial",sans-serif;color:#1D1C1D;background:#F8F8F8">We decided a few years back to stop signing the Adobe Originals, and including a stub DSIG table just in case any implementations try to verify
presence of the table. Also, at the time no one was able to confirm any scenarios that still required a valid signature. We’ve still not seen problems have come up about the lack of actual signature, so I’m in favor of deprecating the use of DSIG altogether.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">—Dan<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">mpeg-otspec <mpeg-otspec-bounces@lists.aau.at> on behalf of "Levantovsky, Vladimir" <Vladimir.Levantovsky@monotype.com><br>
<b>Date: </b>Wednesday, August 26, 2020 at 12:10 PM<br>
<b>To: </b>Peter Constable <pgcon6@msn.com>, Bobby de Vos <bobby_devos@sil.org>, Dave Crossland <dcrossland@google.com>, mpeg-otspec <mpeg-otspec@lists.aau.at><br>
<b>Subject: </b>Re: [MPEG-OTSPEC] DSIG spec issue<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D">FWIW, the stripping of DISG is also a necessity for WOFF2. Due to transforms and data pre-processing / optimization steps applied as part of the WOFF2 encoding steps [that invalidate the DSIG], it is required
that “</span><span style="font-size:13.5pt;font-family:"Arial",sans-serif;color:black;background:white">the compliant WOFF2 encoder <span class="conform">MUST remove the DSIG table from an input font data</span>, prior to applying transformations and entropy
coding steps.</span><span style="color:#1F497D">” (</span><a href="https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2FTR%2FWOFF2%2F%23table_format&data=02%7C01%7Crhatigan%40adobe.com%7Cd4c8c759bb5d437d061608d849da8d37%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C637340550313046438&sdata=NE7FenY%2FYkWNo%2BI6c7FbI0RnnTFMfcjLp1TEQtijxhU%3D&reserved=0">https://www.w3.org/TR/WOFF2/#table_format</a><span style="color:#1F497D">)
</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">I’d say let’s deprecate DSIG once and for all.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">Vlad</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> mpeg-otspec <mpeg-otspec-bounces@lists.aau.at> <b>
On Behalf Of </b>Peter Constable<br>
<b>Sent:</b> Wednesday, August 26, 2020 9:53 AM<br>
<b>To:</b> Bobby de Vos <bobby_devos@sil.org>; Dave Crossland <dcrossland@google.com>; mpeg-otspec <mpeg-otspec@lists.aau.at><br>
<b>Subject:</b> Re: [MPEG-OTSPEC] DSIG spec issue<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Office has a font service, serving fonts to (recent versions of) Office apps. My understanding is that they strip DSIG tables from fonts in the service. So, I would assume that recent versions of Office shouldn’t require DSIG tables to
enable features in Latin fonts, though I haven’t confirmed that.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">This is all product commentary: it can inform whether DSIG may still be relevant for fonts, though of course doesn’t belong in the spec itself.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Peter<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> Bobby de Vos <<a href="mailto:bobby_devos@sil.org">bobby_devos@sil.org</a>>
<br>
<b>Sent:</b> Wednesday, August 26, 2020 6:01 AM<br>
<b>To:</b> Peter Constable <<a href="mailto:pgcon6@msn.com">pgcon6@msn.com</a>>; Dave Crossland <<a href="mailto:dcrossland@google.com">dcrossland@google.com</a>>; mpeg-otspec <<a href="mailto:mpeg-otspec@lists.aau.at">mpeg-otspec@lists.aau.at</a>><br>
<b>Subject:</b> Re: [MPEG-OTSPEC] DSIG spec issue<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p>In addition to triggering the OpenType icon, a DSIG was (is?) needed in older versions of Microsoft Word to process some OpenType features in Latin script fonts.<o:p></o:p></p>
<p><a href="https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fprotect-us.mimecast.com%2Fs%2FWqy2CwpA5KsGM0Z7IqyVTq&data=02%7C01%7Crhatigan%40adobe.com%7Cd4c8c759bb5d437d061608d849da8d37%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C637340550313046438&sdata=lRJ3IlQjgv%2BwvsEBro01TESGyLwyjRor3TK80G3lFsU%3D&reserved=0">https://github.com/googlefonts/fontbakery/issues/1845#issuecomment-564383952</a><o:p></o:p></p>
<p>As recently as Office 2013 this was the case, and Office 2013 has not reached end of life yet.<o:p></o:p></p>
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<p class="MsoNormal">On 2020-08-25 8:01 p.m., Peter Constable wrote:<o:p></o:p></p>
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<p class="MsoNormal">I think at one time, yes, but I don’t think that’s been relevant since Windows 7.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Peter<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> mpeg-otspec <a href="mailto:mpeg-otspec-bounces@lists.aau.at">
<mpeg-otspec-bounces@lists.aau.at></a> <b>On Behalf Of </b>Dave Crossland<br>
<b>Sent:</b> Tuesday, August 25, 2020 6:09 PM<br>
<b>To:</b> mpeg-otspec <a href="mailto:mpeg-otspec@lists.aau.at"><mpeg-otspec@lists.aau.at></a><br>
<b>Subject:</b> Re: [MPEG-OTSPEC] DSIG spec issue<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Wasn't there something about needing a DSIG table to trigger the OpenType icon in Windows Explorer?<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">-- <br>
Bobby de Vos<br>
<em><span style="font-family:"Calibri",sans-serif"><a href="mailto:bobby_devos@sil.org">bobby_devos@sil.org</a></span></em><o:p></o:p></p>
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