[Conversion Output] KFX Output - Page 99

jackm8 · 02-14-2024, 11:19 AM

I'm trying to troubleshoot an error that I get while trying to convert all .epub books in Slovene language that I've tried so far (five books). I'm suspecting something is going off on the side of Kindle Previewer. It's of no massive concern as there is a workaround.

I tried it on five .epub files, all failed with the same error.
Conversion attempt appears to freeze momentarily at line:
"Launching Kindle Previewer 3 (unknown_32741376) - CLI"
Then it ends up with:
"Exception: Conversion error: Kindle conversion has encountered an internal error."

Workaround to this. Conversions into .kfx succeed from .kfs or .epub files that were created in Kindle Create program. For example:

.epub converted to .docx, then to .kfs or .epub in Kindle Create, then to .kfx produces working .kfx.
.epub to mobi/azw3/docx, then using CLI to convert mobi/azw3/docx directly to .kfx, fails with the same error.
.epub to .pdf, then to .kfs in Kindle Create via Print Replica also works, but resulting file is then fixed paged .kfx

Full report from CLI:

Quote:

...>calibre-debug -r "KFX Output" -- "Fran S. Finžgar - Pod svobodnim soncem.EPUB" "Fran S. Finžgar - Pod svobodnim soncem.KFX" -d -p 0
Software versions: KFX Output 2.6.1, calibre 7.4, Windows-10-10.0.19045-SP0
KFX Output plugin help is available at https://www.mobileread.com/forums/sh...d.php?t=272407

Converting Fran S. Finžgar - Pod svobodnim soncem.EPUB
Converting "Fran S. Finžgar - Pod svobodnim soncem.EPUB" to KPF
Launching Kindle Previewer 3 (unknown_32741376) - CLI
**************************************************
Kindle Previewer 3.76.0 Copyright (c) Amazon.com
**************************************************
Checking specified arguments.
Pre-processing in progress.
Processing 1/1 book(s).
Book Conversion failed. ...\Fran S. Finžgar - Pod svobodnim soncem.epub
Post-processing in progress.
Writing output/log files to ...\calibre_vd6tryub\vhdljv_j\ys3ra9w3z53poz2c0mcj \0000

****************** Conversion Failure Reason *****************
Kindle conversion has encountered an internal error.
************************************************** ************

************ Kindle Previewer Conversion Guidance ************
Error Kindle conversion has encountered an internal error.
Recommended Fix: Our team needs to investigate this error in order to resolve. Please go to the KPR Help Menu and select the Send Feedback option to inform us of this issue. Please make sure you are signed in and we will provide you with more information within 3 business days. Thank you.

************************************************** ************
Traceback (most recent call last):
File "runpy.py", line 198, in _run_module_as_main
File "runpy.py", line 88, in _run_code
File "site.py", line 95, in <module>
File "site.py", line 90, in main
File "site.py", line 50, in run_entry_point
File "calibre\debug.py", line 283, in main
File "calibre_plugins.kfx_output.__init__", line 265, in cli_main
File "calibre_plugins.kfx_output.__init__", line 311, in convert_using_previewer
File "calibre_plugins.kfx_output.__init__", line 357, in report_failure
Exception: Conversion error: Kindle conversion has encountered an internal error.

jhowell · 02-14-2024, 04:29 PM

Quote:

Originally Posted by jackm8

I'm trying to troubleshoot an error that I get while trying to convert all .epub books in Slovene language that I've tried so far (five books). I'm suspecting something is going off on the side of Kindle Previewer. It's of no massive concern as there is a workaround.
...
Exception: Conversion error: Kindle conversion has encountered an internal error.

The Kindle Previewer fails with an "internal error" if the book uses an unsupported language.

This plugin has a work-around for some specific languages of temporarily changing the book's language to English for conversion by the Previewer and then restoring the original language in the converted KFX file afterwards. I will add Slovenian (code "sl") in the next release of the plugin.

jackm8 · 02-15-2024, 05:56 PM

Great to know. Funny, I did poke into metadata while trying to fix this, but while I changed other things, I forgot to try changing language. Just changing metadata language to English was enough for all files to convert without an issue.

shamanNS · 02-19-2024, 02:37 PM

Quote:

Originally Posted by jhowell

The Kindle Previewer fails with an "internal error" if the book uses an unsupported language.

This plugin has a work-around for some specific languages of temporarily changing the book's language to English for conversion by the Previewer and then restoring the original language in the converted KFX file afterwards. I will add Slovenian (code "sl") in the next release of the plugin.

Could you also add Serbian (language code "sr" ; and "sh" for rare cases of metadata set as Serbo-Croatian) to that list of languages? I've already tested and confirmed that plugin's work-around code works correctly by manually editing KPR_UNSUPPORTED_LANGUAGES in "original_source_epub.py" file

Or maybe even introduce a plugin tweak to externaly override / redefine that "KPR_UNSUPPORTED_LANGUAGES" list?

jhowell · 02-19-2024, 05:09 PM

Quote:

Originally Posted by shamanNS

Could you also add Serbian (language code "sr" ; and "sh" for rare cases of metadata set as Serbo-Croatian) to that list of languages? I've already tested and confirmed that plugin's work-around code works correctly by manually editing KPR_UNSUPPORTED_LANGUAGES in "original_source_epub.py" file

Or maybe even introduce a plugin tweak to externaly override / redefine that "KPR_UNSUPPORTED_LANGUAGES" list?

I am going to change the plugin to work differently in the next release. Instead of a list of languages that are known to fail conversion I will create a list of languages that are known to work. Any unrecognized language will be changed to English and then the original language will be put back into the KFX file that is created. That will be less effort to maintain in the long run.

shamanNS · 02-20-2024, 07:18 AM

KindleAZWorKFX · 02-28-2024, 11:01 PM

current version of kindle previewer 3 3.76.0, I am pretty sure I have the latest version installed? is the KFX output plugin in calibre already older than the release on kindle's website? or is 3.76.0 not the newest, also converting one eBook.

in KFX output its getting this message about version, which is why I think the KFX output plugin is not up to date with the current build of Kindle Previewer 3.

Launching Kindle Previewer 3 (unknown_32741376) - CLI

Also, I was getting a KPF file is missing message at the end of the ePub output, was able to fix this by converting the ePub format into Kindlegen console app, had dragged the ePub onto it and then imported the outputted Mobi file, and used KindleUnpack plugin into an outputted ePub 2 format eBook and did the converting again to KFX output this time it didn't get that error. so doing this seemed to of fixed that error, also the first time I had my pc offline but unless kindle previewer 3 is required to stay online to convert files, that should not of been the problem. I did check the ePub eBook with calibre eBook editor, using check eBook F7 within edit book T feature, it didn't find any problems but nevertheless it got an missing KPF message the first time, so it must of been something in the code that Kindlegen removed that might of fixed it, not sure exactly but that's how I was able to make a failed KFX, process without an error this time anyway.

also, I was going to use Print to PDF Feature in Calibre E-Book Viewer right click menu with print that does the output to pdf from the source file, to then convert that PDF to KFX if the ePub to Kindlegen then Mobi then KindleUnpack to ePub 2 format to KFX would not work, that should also fix whatever was keeping the ePub to convert correctly if I had tried print to PDF then output that to KFX in theory it would of worked, but I didn't have to try that yet, which is fine. since that keeps the text and images apart, so that in the pdf in edge like text to speech and selectable text works, which may not be needed if your sending it to your kindle paperwhite anyway, but for android or any device that can do text to speech of course, I don't think KFX supports text to speech; but, its handy if you're doing to use a natural voice in Microsoft edge to Read Aloud your eBooks to yourself if you want to listen to them instead of just reading them with your eyes, like with Bluetooth ear pods, then it's a good feature to output to PDF also it might help remove bad code that an ePub E-Book might have maybe.

Nope, it was outdated Kindle Previewer 3, I just had it opened while texting here, its current version it asks to install and update to 3.78.0, so then the download I had was already old for the installer version, I have to convert another eBook in calibre to see if KFX output now checks or sees this version in the output plugin as current.

Nope, current updated version Kindle Previewer 3 3.78.0 is also getting Launching Kindle Previewer 3 (unknown_32771072) - CLI message in calibre. KFX Output plugin version is (2.6.1) by jhowell in calibre, that's the version that is currently up to date on my system. Calibre version is 7.5.1 which is also up to date. if its not clear I am using windows 11, not linux or fedora silverblue, I have that on a older desktop, but I have not played with calibre or used it much under my linux distro on my older desktop yet, so any problems that might happen for me is in the windows version of calibre. I read some of the older text I noticed fedora been used which is fine, I like fedora and opensuse, but not for my currrent desktop is still running windows at this time for my pc games. on the topic of fedora I do prefer Kinoite Fedora 39 with kde plasma over gnome desktop, I liked used gnome for my laptop but my older desktop is running on kde plasma using kinoite at this time. but converting files I am still using windows builds of calibre on my current desktop with the intel i9 processor in it.

I got that Open KFX with Kindle Previewer 3.bat file, used a public domain project Gettysburg eBook converted from ePub to KFX, which has a short table of contents in it, but in under Book Information is saying Table of Contents not specified message, is that normal for the outputted KFX plugin or is that a bug? it shows the table of contents in Kindle Previewer, it's just the Book Information from it. Enhanced Typesetting is supported Cover is Specified and NCX is Specified, Start Reading is Not Specified, Content Language is enlish or en for that, so all the rest looks normal I was just not sure about Table of Contents, it has Table of Contents in Ebook, but the Book Information just says it's Not Specified.

jhowell · 02-29-2024, 10:17 AM

Quote:

Originally Posted by KindleAZWorKFX

is the KFX output plugin in calibre already older than the release on kindle's website?

The KFX Output plugin was last updated on January 29. There have been four new releases of the Kindle Previewer since then. I am not in a hurry to release a new version of KFX Output since the current release works properly with the newer versions of Kindle Previewer, other than reporting an unknown version in the "launching" message. I prefer to not update the plugin more than once a month unless there is a serious problem that needs to be corrected.

Quote:

Originally Posted by KindleAZWorKFX

Also, I was getting a KPF file is missing message at the end of the ePub output, was able to fix this by converting the ePub format into Kindlegen console app, had dragged the ePub onto it and then imported the outputted Mobi file, and used KindleUnpack plugin into an outputted ePub 2 format eBook and did the converting again to KFX output this time it didn't get that error. so doing this seemed to of fixed that error, also the first time I had my pc offline but unless kindle previewer 3 is required to stay online to convert files, that should not of been the problem. I did check the ePub eBook with calibre eBook editor, using check eBook F7 within edit book T feature, it didn't find any problems but nevertheless it got an missing KPF message the first time, so it must of been something in the code that Kindlegen removed that might of fixed it, not sure exactly but that's how I was able to make a failed KFX, process without an error this time anyway.

The "KPF file is missing" error occurs when the Kindle Previewer fails to convert a book to KPF but does not produce an error message explaining why. There are various things in the EPUB being converted that can trigger this to happen. The Kindle Previewer has bugs. Even if an EPUB is technically valid it may not be acceptable to Amazon's conversion software.

As you have found converting to another format and then back to EPUB can sometimes change things enough to work around whatever is causing the failure to convert.

Quote:

Originally Posted by KindleAZWorKFX

I got that Open KFX with Kindle Previewer 3.bat file, used a public domain project Gettysburg eBook converted from ePub to KFX, which has a short table of contents in it, but in under Book Information is saying Table of Contents not specified message, is that normal for the outputted KFX plugin or is that a bug? it shows the table of contents in Kindle Previewer, it's just the Book Information from it. Enhanced Typesetting is supported Cover is Specified and NCX is Specified, Start Reading is Not Specified, Content Language is enlish or en for that, so all the rest looks normal I was just not sure about Table of Contents, it has Table of Contents in Ebook, but the Book Information just says it's Not Specified.

An e-book in EPUB 2 format will typically have two different tables of contents. The inline table of contents is part of the text of the book. And the logical table of contents is metadata that is used to generate the table you see when you open the Go To menu on a Kindle. EPUB 3 allows a single file within the EPUB to serve both purposes.

The Kindle Previewer will show Table of Contents Not Specified in the Book Information display if the metadata of the EPUB that was converted lacks a pointer to the inline table of contents within the book's text. That is a common situation and does not cause any problems because that pointer is only used as a fallback if the book lacks a logical table of contents.

KindleAZWorKFX · 03-01-2024, 01:29 AM

Quote:

Originally Posted by jhowell

An e-book in EPUB 2 format will typically have two different tables of contents. The inline table of contents is part of the text of the book. And the logical table of contents is metadata that is used to generate the table you see when you open the Go To menu on a Kindle. EPUB 3 allows a single file within the EPUB to serve both purposes.

The Kindle Previewer will show Table of Contents Not Specified in the Book Information display if the metadata of the EPUB that was converted lacks a pointer to the inline table of contents within the book's text. That is a common situation and does not cause any problems because that pointer is only used as a fallback if the book lacks a logical table of contents.

So I am thinking, as a home user of using KFX on my kindle paperwhite, its not important how the kfx sees the table of contents, this is not something that I need to fix, for just reading an ebook, and accessing its table of contents, then I just want to confirm for my own personal ebooks I don't need to try to fix this in the Ebook editor options under calibre. I am right that for just reading and accessing them on my reader device, I don't really need Table of Contents to be Specified or I don't need to convert them into epub 3 format then KFX format, as it sounds like it does not matter much, I am correct?

jhowell · 03-01-2024, 03:07 PM

Quote:

Originally Posted by KindleAZWorKFX

So I am thinking, as a home user of using KFX on my kindle paperwhite, its not important how the kfx sees the table of contents, this is not something that I need to fix, for just reading an ebook, and accessing its table of contents, then I just want to confirm for my own personal ebooks I don't need to try to fix this in the Ebook editor options under calibre. I am right that for just reading and accessing them on my reader device, I don't really need Table of Contents to be Specified or I don't need to convert them into epub 3 format then KFX format, as it sounds like it does not matter much, I am correct?

Yes. There is no need for you to change anything related to the table of contents.

jhowell · 03-02-2024, 07:51 AM

Version 2.7.0 - 02 Mar 2024

Detect Kindle Previewer versions up to 3.78.0.

Allow conversion of books using languages that are unsupported by Amazon on Kindles. There is no guarantee that books in unsupported languages will render properly on Kindle devices and apps. For a partial list of supported languages see: Book Supported Languages.

tomsem · 03-02-2024, 02:01 PM

I downloaded some unsupported language texts from Gutenberg: Czech, Hungarian, Hebrew, Tibetan.

No issues with Czech (but Send To Kindle doesn't complain about these) and Hungarian.

Tibetan didn't work: square boxes where the glyphs should be. Adding a custom font with explicit support for Tibetan didn't help. The ePub file previews correctly. I tried side loading the .mobi version but it didn't even show up in Library listing. I tried .txt but it shows boxes with hex codes in them. And you cannot use custom fonts with .txt files. What does Amazon have against Tibetan?

The Hebrew samples from Gutenberg did not specify page-progression-direction="rtl" attribute in <spine> tag. Apple Books figures it out without it and properly assumes 'right binding'. I had to add it explicitly before converting to KFX to achieve correct behavior.

No hyphenation, of course.

jhowell · 03-02-2024, 04:24 PM

Quote:

Originally Posted by tomsem

I downloaded some unsupported language texts from Gutenberg: Czech, Hungarian, Hebrew, Tibetan.

Thanks for testing. Unsupported languages are going to be hit or miss.

tomsem · 03-02-2024, 05:59 PM

Apparently composing Tibetan text is more complicated than I thought. I thought for sure my PocketBook Era would display it, but no.

sinanay · 03-02-2024, 07:31 PM

I've converted a bunch of markdown files to EPUB using Pandoc, and then converted the EPUB file to first AZW3 and then KFX. The AZW3 works fine when I sideload it to my Kindle via Calibre on macOS but the converted KFX file has more margins than I'd like, and the background of the whole page except the margins is very slightly gray - the margins are "transparent" as expected. This also results in all the pixels except the margins to refresh on each page turn.

I searched in the thread with some keywords but I was unable to find anything similar. This is the first time I'm using the plugin, is this a common rookie mistake or am I doing something wrong?

02-15-2024, 05:56 PM	#1473
jackm8 Zealot Posts: 123 Karma: 28464 Join Date: Nov 2015 Device: none	Great to know. Funny, I did poke into metadata while trying to fix this, but while I changed other things, I forgot to try changing language. Just changing metadata language to English was enough for all files to convert without an issue. Last edited by jackm8; 02-15-2024 at 06:02 PM.

02-28-2024, 11:01 PM	#1477
KindleAZWorKFX Connoisseur Posts: 57 Karma: 2378 Join Date: Jul 2018 Location: CA, USA. Device: Kindle Paperwhite Signature Edition and Samsung 10.1 tablet	current version of kindle previewer 3 3.76.0, I am pretty sure I have the latest version installed? is the KFX output plugin in calibre already older than the release on kindle's website? or is 3.76.0 not the newest, also converting one eBook. in KFX output its getting this message about version, which is why I think the KFX output plugin is not up to date with the current build of Kindle Previewer 3. Launching Kindle Previewer 3 (unknown_32741376) - CLI Also, I was getting a KPF file is missing message at the end of the ePub output, was able to fix this by converting the ePub format into Kindlegen console app, had dragged the ePub onto it and then imported the outputted Mobi file, and used KindleUnpack plugin into an outputted ePub 2 format eBook and did the converting again to KFX output this time it didn't get that error. so doing this seemed to of fixed that error, also the first time I had my pc offline but unless kindle previewer 3 is required to stay online to convert files, that should not of been the problem. I did check the ePub eBook with calibre eBook editor, using check eBook F7 within edit book T feature, it didn't find any problems but nevertheless it got an missing KPF message the first time, so it must of been something in the code that Kindlegen removed that might of fixed it, not sure exactly but that's how I was able to make a failed KFX, process without an error this time anyway. also, I was going to use Print to PDF Feature in Calibre E-Book Viewer right click menu with print that does the output to pdf from the source file, to then convert that PDF to KFX if the ePub to Kindlegen then Mobi then KindleUnpack to ePub 2 format to KFX would not work, that should also fix whatever was keeping the ePub to convert correctly if I had tried print to PDF then output that to KFX in theory it would of worked, but I didn't have to try that yet, which is fine. since that keeps the text and images apart, so that in the pdf in edge like text to speech and selectable text works, which may not be needed if your sending it to your kindle paperwhite anyway, but for android or any device that can do text to speech of course, I don't think KFX supports text to speech; but, its handy if you're doing to use a natural voice in Microsoft edge to Read Aloud your eBooks to yourself if you want to listen to them instead of just reading them with your eyes, like with Bluetooth ear pods, then it's a good feature to output to PDF also it might help remove bad code that an ePub E-Book might have maybe. Nope, it was outdated Kindle Previewer 3, I just had it opened while texting here, its current version it asks to install and update to 3.78.0, so then the download I had was already old for the installer version, I have to convert another eBook in calibre to see if KFX output now checks or sees this version in the output plugin as current. Nope, current updated version Kindle Previewer 3 3.78.0 is also getting Launching Kindle Previewer 3 (unknown_32771072) - CLI message in calibre. KFX Output plugin version is (*2.6.1) by jhowell in calibre, that's the version that is currently up to date on my system. Calibre version is 7.5.1* which is also up to date. if its not clear I am using windows 11, not linux or fedora silverblue, I have that on a older desktop, but I have not played with calibre or used it much under my linux distro on my older desktop yet, so any problems that might happen for me is in the windows version of calibre. I read some of the older text I noticed fedora been used which is fine, I like fedora and opensuse, but not for my currrent desktop is still running windows at this time for my pc games. on the topic of fedora I do prefer Kinoite Fedora 39 with kde plasma over gnome desktop, I liked used gnome for my laptop but my older desktop is running on kde plasma using kinoite at this time. but converting files I am still using windows builds of calibre on my current desktop with the intel i9 processor in it. I got that Open KFX with Kindle Previewer 3.bat file, used a public domain project Gettysburg eBook converted from ePub to KFX, which has a short table of contents in it, but in under Book Information is saying Table of Contents not specified message, is that normal for the outputted KFX plugin or is that a bug? it shows the table of contents in Kindle Previewer, it's just the Book Information from it. Enhanced Typesetting is supported Cover is Specified and NCX is Specified, Start Reading is Not Specified, Content Language is enlish or en for that, so all the rest looks normal I was just not sure about Table of Contents, it has Table of Contents in Ebook, but the Book Information just says it's Not Specified. Last edited by KindleAZWorKFX; 02-29-2024 at 12:05 AM. Reason: corrected an few words,and added one more thing. just upgraded Kindle Previewer to 3.78.0 why I edited this. all up to date.

03-02-2024, 02:01 PM	#1482
tomsem Grand Sorcerer Posts: 6,494 Karma: 26425959 Join Date: Apr 2009 Location: USA Device: iPhone 15PM, Kindle Scribe, iPad mini 6, PocketBook InkPad Color 3	I downloaded some unsupported language texts from Gutenberg: Czech, Hungarian, Hebrew, Tibetan. No issues with Czech (but Send To Kindle doesn't complain about these) and Hungarian. Tibetan didn't work: square boxes where the glyphs should be. Adding a custom font with explicit support for Tibetan didn't help. The ePub file previews correctly. I tried side loading the .mobi version but it didn't even show up in Library listing. I tried .txt but it shows boxes with hex codes in them. And you cannot use custom fonts with .txt files. What does Amazon have against Tibetan? The Hebrew samples from Gutenberg did not specify page-progression-direction="rtl" attribute in <spine> tag. Apple Books figures it out without it and properly assumes 'right binding'. I had to add it explicitly before converting to KFX to achieve correct behavior. No hyphenation, of course. Last edited by tomsem; 03-02-2024 at 02:06 PM.

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02-20-2024, 07:18 AM	#1476
shamanNS Guru Posts: 910 Karma: 10500004 Join Date: Feb 2010 Location: Serbia Device: Kindle PW5, Kobo Libra 2, Kindle PW1

03-02-2024, 07:51 AM	#1481
jhowell Grand Sorcerer Posts: 6,528 Karma: 84500001 Join Date: Nov 2011 Location: Tampa Bay, Florida Device: Kindles	Version 2.7.0 - 02 Mar 2024 Detect Kindle Previewer versions up to 3.78.0. Allow conversion of books using languages that are unsupported by Amazon on Kindles. There is no guarantee that books in unsupported languages will render properly on Kindle devices and apps. For a partial list of supported languages see: Book Supported Languages.

03-02-2024, 05:59 PM	#1484
tomsem Grand Sorcerer Posts: 6,494 Karma: 26425959 Join Date: Apr 2009 Location: USA Device: iPhone 15PM, Kindle Scribe, iPad mini 6, PocketBook InkPad Color 3	Apparently composing Tibetan text is more complicated than I thought. I thought for sure my PocketBook Era would display it, but no.

03-02-2024, 07:31 PM	#1485
sinanay Junior Member Posts: 3 Karma: 10 Join Date: Mar 2024 Device: Kindle Oasis 3	I've converted a bunch of markdown files to EPUB using Pandoc, and then converted the EPUB file to first AZW3 and then KFX. The AZW3 works fine when I sideload it to my Kindle via Calibre on macOS but the converted KFX file has more margins than I'd like, and the background of the whole page except the margins is very slightly gray - the margins are "transparent" as expected. This also results in all the pixels except the margins to refresh on each page turn. I searched in the thread with some keywords but I was unable to find anything similar. This is the first time I'm using the plugin, is this a common rookie mistake or am I doing something wrong?