[GUI Plugin] Extract ISBN

[kiwidude]

Originally Posted by ownedbycats

A small request: Is it possible to add an option to have it fail silently if no/identical ISBN is found? I use it as part of a few action chains.

That sounds reasonable, will put it on the list…

[ownedbycats]

Alternately, it could just use the same lower right-corner popup as when it finds a new ISBN, as that's less intrusive.

EDIT: Specifically, this is the problem I have: while it's working fine here, once in a while other dialogs get stuck behind an inactive 'scan failed.' Thankfully all the times it's happened to me there was enough of the title bar peeking out so I could click on it to switch.

[kiwidude]

Release Notes:
https://github.com/kiwidude68/calibr...ct_isbn-v1.6.0

[ownedbycats]

Quick question about ISBN detection:

While adding a new book, at the same time I check the number of chapters I also double-check ISBNs for accuracy. Noticed this in my latest book:

ISBN: 0-7434-3572-9

eISBN: 9781618242228

Extract ISBN pulled the second one -- which is what I wanted, so all's good. But did it fail to detect the dashed ISBN-10, or did it prioritize the latter?

[kiwidude]

@ownedByCats - Impossible for me to say unless you send me the book, did you look at the log file?

[ownedbycats]

Originally Posted by kiwidude

@ownedByCats - Impossible for me to say unless you send me the book, did you look at the log file?

It was this one. The log shows that the ISBN-10s are valid, so it looks like it picked the ISBN-13 (due to it being a 13?):

Starting job: Extract ISBN for 1 books 
=================================================== 
Title:  The Honor of the Queen 
Format: EPUB 
Path:   D:\Documents\My Books\David Weber\The Honor of the Queen (7517)\The Honor of the Queen - David Weber.epub 
--------------------------------------------------- 
  Scanning first 10, then last 5, then remaining 25 files 
      Valid ISBN10: 0743435729 
      Valid ISBN13: 9781618242228 
      Valid ISBN10: 0743435729 
      Invalid ISBN match: 21 99-87041 
  Scan time: 4.52 secs 
  The isbn was found in 4.52 secs 
  New ISBN extracted of: 9781618242228 
=================================================== 
Scan complete, with 0 failures

[kiwidude]

Yes the plugin will prefer ISBN 13 values over ISBN 10 values if it has both.

[ownedbycats]

Another "how does this work?" question.

The Simon & Schuster Speakers Bureau can bring authors to your live event. For more information or to book an event, contact the Simon & Schuster Speakers Bureau at 1-866-248-3049 or visit our website at www.simonspeakers.com. • Book design by Debra Sfetsios • The text for this book is set in Baskerville. • 1209 MTN • Library of Congress Cataloging-in-Publication Data • Draper, Sharon M. (Sharon Mills) • Out of my mind / Sharon M. Draper. — 1st ed. • p. cm. • Summary: Considered by many to be mentally retarded, a brilliant, impatient fifth-grader with cerebral palsy discovers something that will allow her to speak for the first time. • ISBN 978-1-4169-7170-2 (hardcover) • [1. Cerebral palsy—Fiction. 2. People with disabilities—Fiction. 3. Genius—Fiction. 4. Interpersonal relations—Fiction.] I. Title. • PZ7.D78325Ou 2010 • [Fic]—dc22 • 2009018404 • ISBN 978-1-4169-8045-2 (eBook)

All the ISBN-looking number strings listed from the previous excerpt are listed here, except in reverse order:

  Scanning first 10, then last 5, then remaining 25 files 
      Valid ISBN13: 9781416980452 
      Invalid ISBN match: 2009018404 
      Valid ISBN13: 9781416971702 
      Invalid ISBN match: 1-866-248-3049 
  Scan time: 0.98 secs 
  The isbn was found in 0.98 secs 
  New ISBN extracted of: 9781416980452

Does it sometimes scan the files in reverse? I've noticed that when multiple ISBNs are listed, eBook is most often the last, so it'd make sense.

[kiwidude]

Im afraid that sort of question has been asked and answered many times in this thread. There is no “standard” for what ISBN position is in a book, it is at the whim of the publishers. Add in ISBNs for “related” books that they throw in there and there is no rule that can ever be defined to provide a guaranteed particular ISBN. Reverse will give terrible results for as many cases as it will give good ones. Just like looking for particular words being before are just as likely to be after or not present at all.

[ownedbycats]

Yeah, I was mostly just curious why the numbers were in the opposite order as listed in the excerpt. I found a mention of 'the last pages are searched in reverse' when I searched the thread an hour after posting so that answers it.

[Magic815]

Originally Posted by kiwidude

Allowing the user to choose sounds interesting but not without some technical challenges. The way this plugin works is it scans the text of book pages using a regular expression to find numbers that look like an ISBN. So right now all it could do is show the user a list of numbers - not particularly useful given there are no rules for publishers about what order they should be defined and for what purpose. They may even be from an advertisement for another book by that publisher...

So you would have to try to give at least a snippet of text preceding each (which still wouldn't help in the case of an advert). Even that might not necessarily be trivial given how this plugin strips stuff out prior to searching for ISBNs, would have to check.

Then you have all the UI and workflow aspects to consider - right now this runs as a background job in calibre so someone can queue up 50 books and forget about it. You would have to force a UI interaction on them when the job is completed (at least in the circumstances where more than one match is found). Perhaps displaying all the isbns across all the books in a grid and force the user to perhaps tick a box as to which they want from each book group. As one book at a time through some sort of wizard would be too painful to use.

Hence IMO it is a non-trivial change to make that falls very squarely into the rainy day category. It is an interesting suggestion though, and has the potential to reduce some of the noise that has happened in this thread over the years when people come here to exclaim that the plugin should apply rule xyz just because they have a book or two that would work for...

I'm sure if we hooked this into a cloud AI with some learning patterns it would make better choices - but no that isn't going to happen

Yea, it's definitely an interesting problem to solve.

To try and get an idea of the various ways I've seen publishers display the eISBN, below is a collage of screenshots from 15 different eBooks in my Calibre library.
https://i.imgur.com/SLgu71w.png

I feel like if the plugin could possibly use some sort of regex that matches all those variations, it might catch the eISBN 99% of the time. Thoughts?

[ownedbycats]

What if the user could input a custom regex?

[theducks]

Originally Posted by Magic815

I'm glad to see you've taken over this plugin. Yea, it's definitely an interesting problem to solve.

Taken OVER????
Kiwidude ORIGINATED the plugin. He later went on to other things until the last maintainer passed away (unexpectedly) and he stepped in to keep things running for now.

[Magic815]

Originally Posted by ownedbycats

What if the user could input a custom regex?

I was able to get some regex help, and someone came up with the following, which seems to work nicely with a lot of the corner cases I've seen in my eBooks.

https://regex101.com/r/UomIXo/2

Thoughts?

Edit: Although, I just realized that above regex uses the PCRE2 flavor. But am I understanding correctly that Calibre uses this? https://bitbucket.org/mrabarnett/mrab-regex/src/hg/ (Per this page: https://manual.calibre-ebook.com/regexp.html)

[gensuke]

Originally Posted by gviacc

Hi, this worked for me

substitute pdfinfo.exe included in calibre's msi installation with xpdf-tools-win-4.03\bin64

Directory ..\Calibre Portable\Calibre\app\bin

27/01/2021 23:23 1.225.216 pdfinfo.exe
17/02/2022 19:29 1.440.192 pdfinfo.exe_old

Thanks for the info.
On my windows 11 pro (japanese), I found a difference.
the pdfinfo.exe comes with Calibre returns "CreationDate" and "ModDate" with some location info and time zone info written in Japanese characters. While xpdfreader version of pdfinfo.exe doesn't include location and time zone info.
The pdfinfo.exe comes with Calibre has a commandline option "-isodates" which prevents japanese character. So I added this option to get_page_count function in pdf.py
>raw = subprocess.check_output([pdfinfo, '-enc', 'UTF-8', pdf_name, '-isodates'])
This worked for me. But I'm not sure if this modification will cause problem on other platforms.