[NTG-context] XMP metadata schema yields invalid PDF/A
Hi PDF/A files generated using ConTeXt fail validation with veraPDF, and the reason seems to be that the dc:description metadata is defined with the wrong type in the embedded XMP extension schema. https://tex.stackexchange.com/questions/632380/generate-pdf-a-with-context https://github.com/veraPDF/veraPDF-library/issues/1224 I can reproduce the problem using TeX Live 2021 (MkIV 2021.03.05). The definition seems to be controlled by this code. https://source.contextgarden.net/tex/context/base/mkiv/lpdf-pua.xml?search=rdf#l81 Regards -- Karl Pettersson Uppsala, Sweden https://static-dust.klpn.se/ ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
Re: [NTG-context] XMP metadata schema yields invalid PDF/A
On Fri, Feb 04, 2022 at 10:25:27PM +0100, Hans Hagen via ntg-context wrote: > On 2/4/2022 7:29 PM, Karl Pettersson via ntg-context wrote: > > Hi > > > > PDF/A files generated using ConTeXt fail validation with veraPDF, and > > the reason seems to be that the dc:description metadata is defined with > > the wrong type in the embedded XMP extension schema. > > > > https://tex.stackexchange.com/questions/632380/generate-pdf-a-with-context > > > > https://github.com/veraPDF/veraPDF-library/issues/1224 > > > > I can reproduce the problem using TeX Live 2021 (MkIV 2021.03.05). The > > definition seems to be controlled by this code. > > > > https://source.contextgarden.net/tex/context/base/mkiv/lpdf-pua.xml?search=rdf#l81 > so "dc:description" is not permitted? it is mentioned in > > https://www.dublincore.org/specifications/dublin-core/dcmi-terms/#http://purl.org/dc/elements/1.1/description > > (btw it never failed before) The description element is permitted, but the problem seems to be that its valueType is defined as Text in the embedded schema, while the metadata element in the PDF has an embedded structure. https://github.com/veraPDF/veraPDF-library/issues/1224#issuecomment-1029932963 (I suppose the reference to "title" in the issue comment should be "description".) Validating with veraPDF <1.20 does not raise the error. The validation seems to have changed for redefined types in that version. https://github.com/veraPDF/veraPDF-library/blob/integration/RELEASENOTES.md#validation > > Hans > > - > Hans Hagen | PRAGMA ADE > Ridderstraat 27 | 8061 GH Hasselt | The Netherlands >tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl > - > ___ > If your question is of interest to others as well, please add an entry to the > Wiki! > > maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context > webpage : http://www.pragma-ade.nl / http://context.aanhet.net > archive : https://bitbucket.org/phg/context-mirror/commits/ > wiki : http://contextgarden.net > ___ -- Karl Pettersson Uppsala, Sweden https://static-dust.klpn.se/ ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
Re: [NTG-context] XMP metadata schema yields invalid PDF/A
On Sat, Feb 05, 2022 at 12:37:44AM +0100, luigi scarso via ntg-context wrote: > On Fri, Feb 4, 2022 at 11:11 PM Karl Pettersson via ntg-context < > ntg-context@ntg.nl> wrote: > > > On Fri, Feb 04, 2022 at 10:25:27PM +0100, Hans Hagen via ntg-context wrote: > > > On 2/4/2022 7:29 PM, Karl Pettersson via ntg-context wrote: > > > > Hi > > > > > > > > PDF/A files generated using ConTeXt fail validation with veraPDF, and > > > > the reason seems to be that the dc:description metadata is defined with > > > > the wrong type in the embedded XMP extension schema. > > > > > > > > > > https://tex.stackexchange.com/questions/632380/generate-pdf-a-with-context > > > > > > > > https://github.com/veraPDF/veraPDF-library/issues/1224 > > > > > > > > I can reproduce the problem using TeX Live 2021 (MkIV 2021.03.05). The > > > > definition seems to be controlled by this code. > > > > > > > > > > https://source.contextgarden.net/tex/context/base/mkiv/lpdf-pua.xml?search=rdf#l81 > > > so "dc:description" is not permitted? it is mentioned in > > > > > > > > https://www.dublincore.org/specifications/dublin-core/dcmi-terms/#http://purl.org/dc/elements/1.1/description > > > > > > (btw it never failed before) > > > > The description element is permitted, but the problem seems to be that > > its valueType is defined as Text in the embedded schema, while the > > metadata element in the PDF has an embedded > xml:lang="x-default"> structure. > > > > > > https://github.com/veraPDF/veraPDF-library/issues/1224#issuecomment-1029932963 > > > > (I suppose the reference to "title" in the issue comment should be > > "description".) > > > > Validating with veraPDF <1.20 does not raise the error. The validation > > seems to have changed for redefined types in that version. > > > > > > https://github.com/veraPDF/veraPDF-library/blob/integration/RELEASENOTES.md#validation > > > I am missing something here... true > FOO > makes a valid pdf 3a with verapdf 1.20.1. > But dc:description is like dc:title, so where we are redefining > dc:description as Text ? > > -- > luigi Attach metadata xml for the non-validating and validating example (extraced with `pdfinfo -meta | xmllint format -`) in the Github issue. Here is a reference to the description element. Note that only description seems to be redefined, not title. https://source.contextgarden.net/tex/context/base/mkiv/lpdf-pua.xml#l81 > ___ > If your question is of interest to others as well, please add an entry to the > Wiki! > > maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context > webpage : http://www.pragma-ade.nl / http://context.aanhet.net > archive : https://bitbucket.org/phg/context-mirror/commits/ > wiki : http://contextgarden.net > ___ -- Karl Pettersson Uppsala, Sweden https://static-dust.klpn.se/ http://www.w3.org/1999/02/22-rdf-syntax-ns#";> http://purl.org/dc/elements/1.1/"; rdf:about=""> application/pdf AUTHOR TITLE http://ns.adobe.com/pdfx/1.3/"; rdf:about=""> out | 2022-02-02T21:34:48+01:00 out 2022-02-02 21:34 www.pragma-ade.com contextgarden.net 2019.03.21 21:39 tug.org 1.10 7127 5.3 linux-64 http://ns.adobe.com/xap/1.0/"; rdf:about=""> 2022-02-02T21:34:48+01:00 LuaTeX 1.10 7127 + ConTeXt MkIV 2019.03.21 21:39 2022-02-02T21:34:48+01:00 2022-02-02T21:34:48+01:00 http://ns.adobe.com/pdf/1.3/"; rdf:about=""> LuaTeX-1.10 False http://ns.adobe.com/xap/1.0/mm/"; rdf:about=""> uuid:77baf08a-41c6-87cb-47d0-807f764f5064 uuid:fe6c773e-42b0-864d-4c63-da5c57ec1a40 http://www.aiim.org/pdfa/ns/extension/"; xmlns:pdfaProperty="http://www.aiim.org/pdfa/ns/property#"; xmlns:pdfaSchema="http://www.aiim.org/pdfa/ns/schema#"; rdf:about=""> http://ns.adobe.com/pdf/1.3/ pdf Adobe PDF Schema internal A name object indicating whether the document
Re: [NTG-context] XMP metadata schema yields invalid PDF/A
On Sat, Feb 05, 2022 at 09:59:44AM +0100, luigi scarso wrote: > it's not redefined -- it's dropped. And this is ok. > You can also check with > FOO > > > TITLE > > > and again it's valid. > But > https://www.iso.org/obp/ui/#iso:std:iso:19005:-1:ed-1:v2:cor:1:v1:en > and > https://www.iso.org/obp/ui/#iso:std:iso:19005:-1:ed-1:v2:cor:2:v1:en:tab:1 > suggest that dc:description and dc:title are of the same type, > which is coherent with > XMPSpecificationPart1.pdf > as in > https://github.com/adobe/XMP-Toolkit-SDK/tree/main/docs > > I.e. these are correct -- but Subject must agree with dc:description > > > > > > > > TITLE > > > > At least, this is what I understand. > >From what I understand, ConTeXt applies a custom Dublin Core schema containing just a redefinition of dc:description, which is not coherent with how dc:description is written by the application. This patch to lpdf-pda.xml removes the validation error. > -- > luigi -- Karl Pettersson, Sweden Uppsala https://static-dust.klpn.se/ 79a80,97 > > http://purl.org/dc/elements/1.1/ > pdf > Dubline Core > Schema > > > > > internal > Subject in > Document Properties > > description > > Text > > > > > > > > ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
Re: [NTG-context] XMP metadata schema yields invalid PDF/A
> > From what I understand, ConTeXt applies a custom Dublin Core schema > containing just a redefinition of dc:description, which is not coherent > with how dc:description is written by the application. > > This patch to lpdf-pda.xml removes the validation error. > Sorry, diff the other way round according to diff original new. -- Karl Pettersson Uppsala, Sweden https://static-dust.klpn.se/ 80,97d79 < http://purl.org/dc/elements/1.1/ < pdf < Dubline Core Schema < < < < internal < Subject in Document Properties < description < Text < < < < < < < < ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
Re: [NTG-context] XMP metadata schema yields invalid PDF/A
On Sat, Feb 05, 2022 at 03:18:08PM +0100, luigi scarso wrote: > > > Following > https://www.pdfa.org/wp-content/until2016_uploads/2011/08/pdfa_metadata-2b.pdf > I think we should replace > Text > with > Lang Alt > > -- > luigi Yes, if a custom schema is needed at all (from what I can see, the XML does not embed any type definition for dc:title, for example). -- Karl Pettersson Uppsala, Sweden https://static-dust.klpn.se/ ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
