Calibre Cover ID won't verify with ePub

essence · 10-24-2011, 02:42 PM

I might be totally missing something here, but I never used to have this problem. I am getting an "ID invalid" error when trying to verify my ePubs most of the time. (The files work fine, but I need them to get through the ePub verify unless Apple has loosened up their rules.)

After experimenting, it seems to boil down to when the random ID that Calibre assigns to the Cover file in the content.opf file starts with a number. If it starts with the letter, then it is a "legal" ID and it verifies properly.

If I manually change the ID to start with a letter, it passes. But that is a bit of a pain, of course.

Anyone know more about this and if it can be fixed automatically through Calibre?

kovidgoyal · 10-24-2011, 10:10 PM

IIRC the id assigned to cover is always "cover" (this is because some ebook readers stupidly require it to be "cover" and nothing else). So what are you referring to?

essence · 10-25-2011, 10:46 AM

The ID's I'm getting are a long series of numbers and letters. Here is the line in the content.opf that is causing trouble:

<item href="Text/cover.xhtml" id="57ad97cc-957c-4506-9238-172641322ada" media-type="application/xhtml+xml" />

If I change the id to something that starts with a letter, ie. "a7ad97cc-..." then it passes the ePub verification.

If Calibre happens to give it an ID that starts with a letter, then it will pass without any issues. I don't remember that happening a few months ago when I last used Calibre. If I look at an old ePub, it has the cover line written much simpler:

<item href="Text/cover.xhtml" id="cover" media-type="application/xhtml+xml" />

Am I missing something/doing something wrong? Thanks for your help.

kovidgoyal · 10-25-2011, 10:14 PM

Make sure you are running the latest calibre release. Secondly I need a test case that reproduces this behavior to tell you more.

10-24-2011, 02:42 PM	#1
essence Junior Member Posts: 2 Karma: 10 Join Date: Oct 2011 Device: iPad	Calibre Cover ID won't verify with ePub I might be totally missing something here, but I never used to have this problem. I am getting an "ID invalid" error when trying to verify my ePubs most of the time. (The files work fine, but I need them to get through the ePub verify unless Apple has loosened up their rules.) After experimenting, it seems to boil down to when the random ID that Calibre assigns to the Cover file in the content.opf file starts with a number. If it starts with the letter, then it is a "legal" ID and it verifies properly. If I manually change the ID to start with a letter, it passes. But that is a bit of a pain, of course. Anyone know more about this and if it can be fixed automatically through Calibre?

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10-24-2011, 10:10 PM	#2
kovidgoyal creator of calibre Posts: 43,859 Karma: 22666666 Join Date: Oct 2006 Location: Mumbai, India Device: Various	IIRC the id assigned to cover is always "cover" (this is because some ebook readers stupidly require it to be "cover" and nothing else). So what are you referring to?

10-25-2011, 10:46 AM	#3
essence Junior Member Posts: 2 Karma: 10 Join Date: Oct 2011 Device: iPad	The ID's I'm getting are a long series of numbers and letters. Here is the line in the content.opf that is causing trouble: <item href="Text/cover.xhtml" id="57ad97cc-957c-4506-9238-172641322ada" media-type="application/xhtml+xml" /> If I change the id to something that starts with a letter, ie. "a7ad97cc-..." then it passes the ePub verification. If Calibre happens to give it an ID that starts with a letter, then it will pass without any issues. I don't remember that happening a few months ago when I last used Calibre. If I look at an old ePub, it has the cover line written much simpler: <item href="Text/cover.xhtml" id="cover" media-type="application/xhtml+xml" /> Am I missing something/doing something wrong? Thanks for your help.

10-25-2011, 10:14 PM	#4
kovidgoyal creator of calibre Posts: 43,859 Karma: 22666666 Join Date: Oct 2006 Location: Mumbai, India Device: Various	Make sure you are running the latest calibre release. Secondly I need a test case that reproduces this behavior to tell you more.

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