metadata tags

[Budfudder]

I notice that there are some metadata tags that Calibre appears unable to address, and some it is able to change, but not remove.

For example, I can't find anything in the documentation about modifying the value for the 'Copyright' tag, and I can't find a way to remove the value for the 'Languages' or 'Published' or 'Identifiers' tags.

Is this by design, or am I simply doing something wrong?

I use ebook-meta.exe mostly, rather than the GUI, if that makes any difference.

[eschwartz]

Specify a null value for languages/publisher - it gets reset to the default. (english, published 0101-01-01T00:00:00+00:00)
It makes no sense to have a book without a language, or one that was never published (or at least written). Or so I would assume.


identifiers -- you need to clear each identifier (as stated in the --help).

ebook-meta /path/to/ebook --identifier "identifier-type:"

Copyright -- what copyright tag?

[BetterRed]

@Budfudder - apart from Language all standard metadata items can be individually cleared by clicking the green 'recycle' buttons



BR

[theducks]

I believe some meta tags are mandatory.
Clearing them, will allow the system default to be filled in on exiting.

[BetterRed]

Originally Posted by theducks

I believe some meta tags are mandatory.
Clearing them, will allow the system default to be filled in on exiting.

PDFs do not have a specific place to put Language unless you embed it in XML. If you create a book via PDF there will be nothing in Language. If you create a book with a Text file then all bets are off - methinks you're being too EPUB centric.

Why has this thread been moved to the Book Editor sub-forum? I thought it was about metadata

BR

[eschwartz]

Well, calibre also knows about the Language, so it will be in the calibre metadata.
What calibre metadata goes into the ebook file is often a subset of available metadata -- only EPUB can support any arbitrary metadata types.

ebook-meta, or the GUI, will certainly try to set the default value for certain "mandatory" metadata.

[theducks]

Originally Posted by BetterRed

PDFs do not have a specific place to put Language unless you embed it in XML. If you create a book via PDF there will be nothing in Language. If you create a book with a Text file then all bets are off - methinks you're being too EPUB centric.

Why has this thread been moved to the Book Editor sub-forum? I thought it was about metadata

BR

Moved because the OP was editing various places and it would not stay gone. I assume, this was in the book since they wanted Blank.

BTW Rights (copyright is a DTD field), which is another reason I figured this was an Edit

I guess Language also defaults (non blank) on the spreadsheet.

[BetterRed]

Actually Language, like other editable metadata items, can be cleared by editing, via F2, in the book list and entering '-'.

The only metadata items I can think of that cannot be edited are the id and the UUID because there's no place where they're presented in an editable form.

BR

[Budfudder]

Originally Posted by eschwartz

Specify a null value for languages/publisher - it gets reset to the default. (english, published 0101-01-01T00:00:00+00:00)
It makes no sense to have a book without a language, or one that was never published (or at least written). Or so I would assume.


identifiers -- you need to clear each identifier (as stated in the --help).

ebook-meta /path/to/ebook --identifier "identifier-type:"

Copyright -- what copyright tag?

Thanks for your help.

For clearing identifiers, I can get rid of the isbn by using:

--identifier isbn:

but I've found no way I can get ride of the mobi-asin. I've tried:

--identifier mobi-asin:
--identifier=mobi-asin:
--identifier="mobi-asin:"
--identifer= "mobi-asin:"

nothing seems to work.

Also, how do I get rid of the tags metadata? I can empty it, but it still shows when I use ebook-meta on the file - it just shows with no data

And sorry, not 'Copyright' - I meant 'Rights'. ebook-meta doesn't even recognise the parameter "--right=" or "--rights="

[eschwartz]

What "rights" tag?



As for mobi-asin -- you cannot get rid of that, it is automatically based off of a MOBI header used for internal bookkeeping. It would be like trying to get rid of an EPUB uuid.

[Budfudder]

Originally Posted by eschwartz

What "rights" tag?

As for mobi-asin -- you cannot get rid of that, it is automatically based off of a MOBI header used for internal bookkeeping. It would be like trying to get rid of an EPUB uuid.

The Rights tag as in this ebook-meta output:

Title : Ali Pacha
Author(s) : Alexandre Dumas
Tags :
Languages : eng
Published : 0101-01-01T00:00:00+00:00
Rights : Public domain in the USA.
Identifiers : mobi-asin:491da94a-0a31-409e-9d3b-2f8ed5829248

Also, what about the 'Tags' tag? How can I get rid of that?

Thanks for the info about the mobi-asin tag.

[eschwartz]

That would appear to be a custom column. So I guess your question is really "how can I manipulate calibre custom columns using ebook-meta?"

Answer: I don't think you can, because custom columns need the database to define what data type they are.
You could kludge something together --from-opf of course...

FWIW, `calibredb set_metadata` can set custom columns in the database, and `calibredb embed_metadata` can embed them into the ebook files.

[Budfudder]

Originally Posted by eschwartz

What "rights" tag?

As for mobi-asin -- you cannot get rid of that, it is automatically based off of a MOBI header used for internal bookkeeping. It would be like trying to get rid of an EPUB uuid.

About the mobi-asin tag - how can it be that it can't be gotten rid of, when some .mobi files don't have it?

[eschwartz]

Because it isn't metadata as calibre understands it.

mobi-asin is automatically picked up from the exth 113 (ASIN) header, which is usually used to show a link to the Amazon store. If that header has content in it, Kindles will stop showing the "Personal" banner.

Changing it requiires conversion in calibre (there are MOBI output options that control its creation) or modifying the exth headers using something like Java Mobi Metadata Editor.



ebook-meta cannot get rid of this non-standard mobi-specific metadata field, but it can read and import it into the "identifiers" metadata, which is what is confusing you.

[Budfudder]

Originally Posted by eschwartz

Because it isn't metadata as calibre understands it.

mobi-asin is automatically picked up from the exth 113 (ASIN) header, which is usually used to show a link to the Amazon store. If that header has content in it, Kindles will stop showing the "Personal" banner.

Changing it requiires conversion in calibre (there are MOBI output options that control its creation) or modifying the exth headers using something like Java Mobi Metadata Editor.

ebook-meta cannot get rid of this non-standard mobi-specific metadata field, but it can read and import it into the "identifiers" metadata, which is what is confusing you.

I think I see now. Sorry for my ignorance, and thanks for taking the time to explain it to me.