Apple Books EPUB check complains about property 'svg' not being declared in OPF file

[Inélsòre]

Hello,

while uploading a Fixed Layout EPUB to Apple Books (here we go again...), I got the usual error of a PNG being oversized, which I learned to fix easy enough, plus another error which I had never seen before:

ERROR ITMS-9000: Apple-Kummer44-Score-Parts.epub: OEBPS/Apple-Kummer44-Score-Parts-80.xhtml(-1): [OPF-014] The property 'svg' should be declared in the OPF file. (For more information refer to https://help.apple.com/itc/booksassetguide)

Of course, at the link provided, there is only the full length guide, not anything actually useful in the short term. I opened the file mentioned in the error and the OPF file. Now: what should I do with it? How could I edit it so that Apple Books doesn't complain? 

It seems it is complaining about the barcode I have added to the edition, which is basically the only truly different thing compared to previous editions. Barcode has been generated as SVG from this website: https://barcode.tec-it.com/en. 

Files available here: https://www.icloud.com/iclouddrive/0fcfDJ_44pyCfTlCtPPxgpNoA#AppleBooks-issue

Any help appreciated!

Thanks

[James Gifford—NitroPress]

To start with, you should update to v18.1 as soon as it's available to you. It has a number of changes to EPUB export, some long-standing requests, a reversion of the added elements that came with 18.0, and I suspect more "cleanup and fixing" that's not specfically noted.

That alone may solve some of the issues you (and all of us) have been encountering. Your issue may be in that middle category of the EPUB code padding that (probably according to standards, but) has been confusing various validation processes.

That said, out there at the intersection of Apple's reader + SVG + your many special needs with music scores... one thing at a time. 🙂

But 18.1 may well be a boon for all of us who use EPUB exports.

[Inélsòre]

Updated, tried export again, uploaded to Apple Books, same error again ... 

Any new idea?

[James Gifford—NitroPress]

Okay, well, it's useful to know it wasn't another of the (unnecessary) additions to EPUB code that 18.0 was doing.

I'd place the barcode as another format., or find another generator that creates a more compliant SVG. Seems simple enough, at least from over here. 🙂

[Inélsòre]

Any suggestion about another barcode generator that you would rely upon?

[Marvest]

https://bookow.com/

[James Gifford—NitroPress]

There are dozens. I suggest that it's not the generator but the format; SVG is just too dang 'tetchy' for me. One of those formats, kind of like EPUB itself, that no one does quite right or quite the same way, leading to endless headaches.

Try a simple PNG.

[Inélsòre]

Problem with PNG is that InDesign creates as many blank PNGs as there are pages in the InDesign document when exporting to EPUB. I have never understood why it did that, but the only way to circumvent most of it was to alter the export settings so that images would become PNG at 72ppi (the minimum). 

Doing this reduced the amount of extra work to reduce those images that were more than 4 million pixels (quite a strict requirement from Apple...). At the same time, 72ppi would make the code illegible.

Now that I think of it, though: barcodes are only used by shops and warehouses to process SKUs and similar, right? What use do I have of a barcode for an EPUB, all considering? I already have the ISMN code in there, no need for barcode, if this is the only issue I have, right? 

[James Gifford—NitroPress]

I ass/u/med it was yet another requirement of Apple's.

[Inélsòre · Accepted solution]

With the very little, or nothing, that I know about HTML, I added this 

properties="svg"

at the end of the line described in the error and ... the upload succeeded.

What I find fascinating is that eveyr time I upload to Apple something different happens!

I will consider that ... training! 

[James Gifford—NitroPress]

Very clever! Yes, EPUB does demand work at the code level sometimes.

I can't say whether mastering one service's quirky demands counts as forward progress or not, but I'm a champion of standards across things like EPUB publishing, not accommodating each player's quirks. 🙂