Comparing new proposal for continuously scrolled comics with Kadokawa's example

kadokawa.xml

<?xml version="1.0" encoding="UTF-8"?>
<package
 xmlns="http://www.idpf.org/2007/opf"
 version="3.0"
 xml:lang="ja"
 unique-identifier="bw-ecode"
 prefix="rendition: http://www.idpf.org/vocab/rendition/#
 ebpaj: http://www.ebpaj.jp/
 fixed-layout-jp: http://www.digital-comic.jp/
 kadokawa: http://www.kadokawa.co.jp/
 access: http://www.access-company.com/2012/layout#
 ibooks: http://vocabulary.itunes.apple.com/rdf/ibooks/vocabulary-extensions-1.0/"
 >

  <metadata xmlns:dc="http://purl.org/dc/elements/1.1/">

    <!-- 作品名 -->
    <dc:title id="title">作品名</dc:title>
    <meta refines="#title" property="file-as">サクヒンメイ</meta>

    <!-- 著者名 -->
    <dc:creator id="creator01">著訳者名</dc:creator>
    <meta refines="#creator01" property="role" scheme="marc:relators">aut</meta>
    <meta refines="#creator01" property="file-as">チョヤクシャメイ</meta>
    <meta refines="#creator01" property="display-seq">1</meta>


    <!-- 出版社名 -->
    <dc:publisher id="publisher">株式会社ＫＡＤＯＫＡＷＡ</dc:publisher>
    <meta refines="#publisher" property="file-as">カブシキガイシャカドカワ</meta>

    <!-- 言語 -->
    <dc:language>ja</dc:language>

    <!-- ファイルid -->
    <dc:identifier id="bw-ecode">04000000A00000000000</dc:identifier>

    <!-- 更新日 -->
    <meta property="dcterms:modified">2021-08-11T00:00:00Z</meta>

    <!-- レンダリング指定 -->
    <meta property="rendition:layout">pre-paginated</meta>
    <meta property="rendition:orientation">auto</meta>
    <meta property="rendition:spread">none</meta>
    <meta property="rendition:flow">scrolled-continuous</meta>

    <!-- etc. -->
    <meta property="ebpaj:guide-version">1.1.3</meta>
    <meta property="kadokawa:version">1.3.1</meta>
    <meta property="kadokawa:fix">1.3.1</meta>
    <meta property="ibooks:specified-fonts">true</meta>
    <meta property="ibooks:binding">false</meta>
    <meta name="book-type" content="comic"/>
    <meta name="original-resolution" content="760x1000"/>
    <meta name="orientation-lock" content="none"/>
    <meta name="scroll-direction" content="ttb"/>


    <!-- 基準サイズ -->
    <meta property="fixed-layout-jp:viewport">width=760, height=1000</meta>

  </metadata>

  <manifest>

    <!-- navigation -->
    <item media-type="application/xhtml+xml" id="toc" href="navigation-documents.xhtml" properties="nav"/>

    <!-- style -->
    <item media-type="text/css" id="fixed-layout-jp" href="style/fixed-layout-jp.css"/>
    <item media-type="text/css" id="book-style"      href="style/book-style.css"/>
    <item media-type="text/css" id="style-reset"     href="style/style-reset.css"/>
    <item media-type="text/css" id="style-standard"  href="style/style-standard.css"/>
    <item media-type="text/css" id="style-advance"   href="style/style-advance.css"/>
    <item media-type="text/css" id="style-check"     href="style/style-check.css"/>
    <item media-type="text/css" id="style-karc"      href="style/style-karc.css"/>
    <item media-type="text/css" id="style-kadokawa"  href="style/style-kadokawa.css"/>

    <!-- image -->
    <item media-type="image/jpeg" id="cover" href="image/cover.jpg" properties="cover-image"/>
    <item media-type="image/jpeg" id="i-001" href="image/i-001.jpg"/>
    <item media-type="image/jpeg" id="i-002" href="image/i-002.jpg"/>
    <item media-type="image/jpeg" id="i-003" href="image/i-003.jpg"/>
    <item media-type="image/jpeg" id="i-004" href="image/i-004.jpg"/>
    <item media-type="image/jpeg" id="i-005" href="image/i-005.jpg"/>
    <item media-type="image/jpeg" id="i-tatesuku" href="image/i-tatesuku.jpg"/>

    <!-- xhtml -->
    <item media-type="application/xhtml+xml" id="p-cover" href="xhtml/p-cover.xhtml" properties="svg" fallback="cover"/>
    <item media-type="application/xhtml+xml" id="p-001" href="xhtml/p-001.xhtml" properties="svg" fallback="i-001"/>
    <item media-type="application/xhtml+xml" id="p-002" href="xhtml/p-002.xhtml" properties="svg" fallback="i-002"/>
    <item media-type="application/xhtml+xml" id="p-003" href="xhtml/p-003.xhtml" properties="svg" fallback="i-003"/>
    <item media-type="application/xhtml+xml" id="p-004" href="xhtml/p-004.xhtml" properties="svg" fallback="i-004"/>
    <item media-type="application/xhtml+xml" id="p-005" href="xhtml/p-005.xhtml" properties="svg" fallback="i-005"/>
    <item media-type="application/xhtml+xml" id="p-tatesuku" href="xhtml/p-tatesuku.xhtml" properties="svg" fallback="i-tatesuku"/>

  </manifest>

  <spine page-progression-direction="rtl">
    <itemref linear="yes" idref="p-cover" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-001" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-002" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-003" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-004" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-005" properties="rendition:page-spread-center"/>
    <itemref linear="yes" idref="p-tatesuku" properties="rendition:page-spread-center"/>
  </spine>

</package>

proposal.xml

<?xml version="1.0" encoding="UTF-8"?>
<package
 xmlns="http://www.idpf.org/2007/opf"
 version="3.0"
 xml:lang="ja"
 unique-identifier="bw-ecode"
 prefix="rendition: http://www.idpf.org/vocab/rendition/#">

   <metadata xmlns:dc="http://purl.org/dc/elements/1.1/">

    <dc:title id="title">作品名</dc:title>
    <meta refines="#title" property="file-as">サクヒンメイ</meta>

    <dc:language>ja</dc:language>

    <dc:identifier id="bw-ecode">04000000A00000000000</dc:identifier>
    <meta property="dcterms:modified">2021-08-11T00:00:00Z</meta>

    <meta property="rendition:layout">scrolled</meta>

  </metadata>

  <manifest>

    <!-- navigation -->
    <item media-type="application/xhtml+xml" id="toc" href="navigation.xhtml" properties="nav"/>

    <!-- image -->
    <item media-type="image/jpeg" id="cover" href="image/cover.jpg" properties="cover-image" fallback="p-cover"/>
    <item media-type="image/jpeg" id="i-001" href="image/i-001.jpg" fallback="p-001"/>
    <item media-type="image/jpeg" id="i-002" href="image/i-002.jpg" fallback="p-002"/>
    <item media-type="image/jpeg" id="i-003" href="image/i-003.jpg" fallback="p-003"/>
    <item media-type="image/jpeg" id="i-004" href="image/i-004.jpg" fallback="p-004"/>
    <item media-type="image/jpeg" id="i-005" href="image/i-005.jpg" fallback="p-005"/>
    <item media-type="image/jpeg" id="i-tatesuku" href="image/i-tatesuku.jpg" fallback="p-tatesuku"/>

    <!-- xhtml -->
    <item media-type="application/xhtml+xml" id="p-cover" href="xhtml/p-cover.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-001" href="xhtml/p-001.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-002" href="xhtml/p-002.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-003" href="xhtml/p-003.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-004" href="xhtml/p-004.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-005" href="xhtml/p-005.xhtml"/>
    <item media-type="application/xhtml+xml" id="p-tatesuku" href="xhtml/p-tatesuku.xhtml"/>

  </manifest>

  <spine>
    <itemref idref="cover"/>
    <itemref idref="i-001"/>
    <itemref idref="i-002"/>
    <itemref idref="i-003"/>
    <itemref idref="i-004"/>
    <itemref idref="i-005"/>
    <itemref idref="i-tatesuku"/>
  </spine>

</package>

We use many metadata and they ware set for compatibility with Apple and Amazon's reading systems more than 10 years ago.
But some of them can be deleted now, actually. We just left them because they don't have any bad effects.

In Japan, some reading systems have two engines for text and comics, so it's useful if they can determin by OPF.

In Japan, some reading systems have two engines for text and comics, so it's useful if they can determin by OPF.

This feels like an important piece of information that hasn't been brought up until now. We should cover this issue within the Digital Comics TF as well.

Is this achieved using these various version metadata or using the Kindle metadata (book-type)?