Fascinating insights.
The original EPUB file edits fine, and converts fine, and of course, Amazon convers the 'tampered metadata' EPUB file fine, and the 'tempered metadata' EPUB reads fine even in the Calibre Ebook native on-screen reader.
Calibre Ebook can read and display the EPUB just fine, but cannot open the 'tempered metadata' EPUB to edit, save metadata, polish, or covert the EPUB to another format.
Calibre Ebook program was the only thing that touched the EPUB, and I used the various auto-fix features copiously without error before saving and exiting out before then trying to convert:
And Calibre Ebook puts it's own # in the custom column control panel, I did not put a # in the column name, see here:
The ODF file is 17 KB and has no # marks in it, according to Windows Notepad character search.
===========================================
I CAN duplicate the error, starting with a fresh copy of the original EPUB before editing.
When simplifying and flattening a table of contents ( all entries are h2 at the top of their own separate page file, subordinate 'headings' inside a 'chapter' are converted to <p><b>...</b></p> and are no longer in the table of contents), and then removing the 'noise' after #, such as #toc_1", #toc_2" in table of contents and reference files, replacing:
with
. . . "check book" says all is OK.
But save and exit, then I can't re-open the book for editing or converting.
Ouch!
So, on the one hand, don't clean up the ...#toc"-style table of contents references, even though "check book" says those are errors.
On the other hand, why does "check book" think a file is then OK with those errors removed if then the file can never be opened again after saving?
And, most importantly, why can't Calibre Ebook 'fix' the error on reopening the file to allow the user to get to the EPUB
contents regardless of any metadata errors ( metadata errors that are apparently meaningless to Caliber Ebook's own
reader and meaningless to
Amazon's converter )?
In other words, thanks for the report on metadata, but as an end user, I'm using Calibre Ebook as an
ebook editor ( primarily ), not a
metadata editor ( a hopefully invisible yet discardable thing to us end users ).
That Calibre Ebook editor can manipulate metadata is terrific, but subordinate to the actual authored ( 'precious' )
contents of an ebook.
My goal is to strip an ebook file down to essentially only what can be heard when reading the contents out loud - that does not include metadata in anyway ( though I understand there may be metadata codes for read-out-loud programs to control pauses, inflection, and such, but such audio metadata is not on my event horizon at the moment ).
All that aside:
. . . could there be a way for Calibre Ebook to offer to open the contents of an ebook stripped of it's metadata, especially when Calibre Ebook finds errors in the metadata?
. . . instead of just saying "I can't open this ebook's contents, it's too hard to figure out what's what".
Or separately, is there a way to 'import' just the ebook's authored contents on demand?
==========================================
OK, three things:
1 - the "check book" inside the editor seems out of sync with the book checking routines in the external main-window parts of the Calibre Ebook program, such that they do not agree with each other whether an EPUB is OK or not - it would be nice if the editor's "check book" had the
same savvy and warning BEFORE exiting the ebook editor to then never be able to reopen it for editing.
2 - It would be terrific if the editor, upon opening an ebook, offered to fix broken metadata, even tossing metadata if necessary, to allow the user to at least get to the authored ebook contents, even if devoid of formatting or demarcations that metadata might have provided.
3 - is there a way to import a stripped ebook without it's metadata?
Thanks.
.