validation errors


I Converted a DAISY2.02 book to EPUB3 by Pipeline2. Then I Opened a EPUB3 book by Tobi to edit metadata. Following 3 errors and 1 warning appeared when I try to export a EPUB3 by Tobi. How can I avoid those errors?

ERROR: C:/temp/epub3/_package_opf-三匹の子ぶた.xukspine_EX/三匹の子ぶた.epub/EPUB/package.opf(24,19): element "dc:Contributor" not allowed anywhere; expected the element end-tag or element "dc:contributor", "dc:coverage", "dc:creator", "dc:description", "dc:format", "dc:identifier", "dc:language", "dc:publisher", "dc:relation", "dc:rights", "dc:source", "dc:subject", "dc:title", "dc:type", "link" or "meta"
ERROR: C:/temp/epub3/_package_opf-三匹の子ぶた.xukspine_EX/三匹の子ぶた.epub/EPUB/package.opf(209,13): toc attribute references resource with non-NCX mime type; "application/x-dtbncx+xml" is expected
ERROR: C:/temp/epub3/_package_opf-三匹の子ぶた.xukspine_EX/三匹の子ぶた.epub/EPUB/package.opf(209,13): assertion failed: spine element toc attribute must reference the NCX manifest item (referenced media type was 'text/xml')
WARNING: C:/temp/epub3/_package_opf-三匹の子ぶた.xukspine_EX/三匹の子ぶた.epub/EPUB/Content/ncx.xml: meta@dtb:uid content '' should conform to unique-identifier in content.opf: 'jsrpd-pigs-j'

Hello Mayu, could you please check that the Pipeline2-created EPUB3 is valid (immediately after the conversion from DAISY 2.02). You can use epub-check (separate download), or you can let Tobi verify your EPUB3 when you import it to create a new project. Thank you! Daniel

Hi Daniel,
Thank you for your reply.
EPUB3 created by Pipeline2 is valid (checked with pagina EPUB-Checker and also Tobi varify when importing). Have one "warning" but no error.
You can download a book from the following link.

Some other sample books converted from DAISY2.02 to EPUB3 by Pipeline2


Thank you Mayu, I am now investigating the issue. I also tested the "pigs" and "match" books with the latest version of Readium (not yet released), I will send you a link to try yourself. Regards, Daniel

Hello again, first of all, on my english machine when I run epubcheck from Tobi immediately after export, the japanese characters in the filename 三匹の子ぶた.epub become question marks '?', and epubcheck reports an error (because it fails to find the file). Fortunately, I can validate the english version of the same book ("pigs"). I cannot reproduce the "dc:Contributor" error. The original EPUB books (from your download link) contain the correct lower-case name "dc:contributor". Are you sure you are working with the same book? I can however reproduce the "application/x-dtbncx+xml" mime-type error. This is a bug in Tobi. The warning about meta@dtb:uid is in the original NCX, and Tobi does not change it, so the epubcheck warning remains. So, I am now checking the NCX mime-type bug. Hopefully a quick fix. Daniel

Hi Daniel,
Thank you for investigation.
I forgot to say that I opened a book by Tobi because I wanted to edit metadata. I added contributor on Tobi and the selection at the pulldown menu of metadata at Tobi was "dc:Contributor".

Hello Mayu, the NCX mime/media-type export bug is fixed, thank you for reporting! Regarding the metadata editor, this is a known caveat. Tobi was written for simple DAISY metadata, but EPUB3 offers a much more complex set of options, which the editor cannot handle. Furthermore, the DAISY "dc:" names are slightly different than EPUB. So, when you pick dc:Contributor, please change the upper case 'C' to lower case 'c'. I will see what I can do on Tobi's side to auto-fix such obvious issue, but I cannot promise a fully EPUB-compatible metadata editor. Here is another tip: export to EPUB3 from Tobi, then look inside the file-browser window, next to the EPUB file there is a directory which contains the unzipped contents of the EPUB. You can manually make changes in the package.opf file (for example, add dc:contributor using copy/paste), then when you are finished, drag+drop the zip folder onto Tobi => Tobi will create the zipped EPUB file again. Regards, Daniel

Thank you very much for the detailed information and a tip.
I'd love to try latest Readium!