MOBI support for reflowable files ending on June 28, 2021

[Hitch]

Originally Posted by Quoth

Calibre saves plain old mobi (KF7) as mobi
Calibre saves dual old mobi (KF7 + KF8) as mobi
I think Calibre saves KF8 (newer Mobi) as azw3

AFAIK, "dual old mobi" is an oxymoron. There is no dual old mobi (do you mean KF8?); in Calibre, that's AZW or AZW3, whichever is Calibre's versus KDP's. (I can never remember. Yes, it's peculiar, what can I say?).

There is, even to this day, Old MOBI/KF7, or Dual MOBI (AZW-whatever) for Calibre. Now, if you mean a MOBI made by someone else, a "KF8" mobi, then yes, you can have a file with dual interior files with the file extension of MOBI.

It's unclear to me if we mean "files from anywhere," or "files made by Calibre," so...that's my clarification. IF files made somewhere else, by somebody else, are included in the discussion, then yes, there are 3 possibilities in the MOBI family.

Hitch

[stefano.sb]

Originally Posted by jhowell

I do not know of any automated way to do that.

One manual method to do it one book at a time is to use the KindleUnpack plugin to see what is inside the MOBI format. If it produces a "mobi7" folder containing a "book.html" file then the old format is present. If it produces a "mobi8" folder then the new format is present. Both for both.

Thanks @jhowell it works!!!! As you wrote it's necessary to do that one book at a time :-(

I notice that when I select an OLD or a NEW MOBI ebook the plugin has only a "Unpack MOBI" sub-menu under MOBI menu. When I select a BOTH MOBI ebook there is also a "MOBI->Split KF8/MOBI..." sub-menu always under MOBI menu. KindleUnpack recognizes a BOTH version "before" unpack it...

Perhaps by asking @DiapDealer in the "[GUI Plugin] KindleUnpack - The Plugin" thread....

Stefano

[Quoth]

Originally Posted by Hitch

AFAIK, "dual old mobi" is an oxymoron. There is no dual old mobi (do you mean KF8?); in Calibre, that's AZW or AZW3, whichever is Calibre's versus KDP's. (I can never remember. Yes, it's peculiar, what can I say?).

Sorry for being confusing. The Dual mobi of Calibre seems to be old mobi (KF7) + KF8. I've not checked to see are the images only included once. It's saved with .mobi file ending. A KF8 only version is saved as azw3

Amazon has more kinds of mobi as there is a fixed layout that seems to be more based on PDF than HTML3. Calibre doesn't make it.

[stefano.sb]

Originally Posted by jhowell

.....
MOBI: Based on HTML 3. Can be emailed or sideloaded. Will sync annotations and reading position across devices if emailed. Will show a cover thumbnail on Kindle devices. Some complex formatting may be lost during conversion to this format.
......

Hi,
below the results of I little test that I made. I have a MOBI ebook not converted with Calibre. If I sideload it via emai, Kindle shows a cover thumbnail only in "Home" page/view. It's not show cover either in "Library" page/view or in context menu that appears if I long press on the ebook cover

The same ebook converted with Calibre (MOBI to MOBI) shows correctly the cover thumbnail in all situations if I sideload it via email

I have a Kindle Paperwhite 11 with fw 5.14.2

Stefano

[Hitch]

Originally Posted by stefano.sb

Hi,
below the results of I little test that I made. I have a MOBI ebook not converted with Calibre. If I sideload it via emai, Kindle shows a cover thumbnail only in "Home" page/view. It's not show cover either in "Library" page/view or in context menu that appears if I long press on the ebook cover

The same ebook converted with Calibre (MOBI to MOBI) shows correctly the cover thumbnail in all situations if I sideload it via email

I have a Kindle Paperwhite 11 with fw 5.14.2

Stefano

Stefano?

You forgot the results?

Hitch

[stefano.sb]

Originally Posted by Hitch

Stefano?

You forgot the results?

Hitch

No... these are the results.... I have found differences in cover thumbnails when I sideload a MOBI ebook not created with Calibre and another created with it:

... If I sideload via emai a MOBI ebook not converted with Calibre, Kindle shows a cover thumbnail only in "Home" page/view. It not show cover either in "Library" page/view or in context menu that appears if I long press on the ebook cover

The same ebook converted with Calibre (MOBI to MOBI) shows correctly the cover thumbnail in all situations when it's sideloaded it via email...


.. only this I know only that both of them are MOBI7 file type

Stefano

[Hitch]

Originally Posted by stefano.sb

No... these are the results.... I have found differences in cover thumbnails when I sideload a MOBI ebook not created with Calibre and another created with it:

... If I sideload via emai a MOBI ebook not converted with Calibre, Kindle shows a cover thumbnail only in "Home" page/view. It not show cover either in "Library" page/view or in context menu that appears if I long press on the ebook cover

The same ebook converted with Calibre (MOBI to MOBI) shows correctly the cover thumbnail in all situations when it's sideloaded it via email...


.. only this I know only that both of them are MOBI7 file type

Stefano

Calibre dudes:

Isn't this a known thing? That the whole "Calibre doesn't display my cover" is a known behavior? Or am I hallucinating? Doesn't this have to do with the meta delivered by Amazon, for a "book" versus a document or some such?

Stefano, have you researched this at the Calibre users' forum here on MR?

Hitch

[jhowell]

Originally Posted by stefano.sb

I have a MOBI ebook not converted with Calibre. If I sideload it via emai, Kindle shows a cover thumbnail only in "Home" page/view. It's not show cover either in "Library" page/view or in context menu that appears if I long press on the ebook cover

Without knowing more about how you created this MOBI file it is difficult to speculate as to why the cover isn't working.

[stefano.sb]

Originally Posted by jhowell

Without knowing more about how you created this MOBI file it is difficult to speculate as to why the cover isn't working.

Hi, it's true! I agree with you jhowell! Attached there is a zip file with the two MOBI versions of the same ebook. The one with the file name ending with "NO CALIBRE.mobi" is the version NOT converted with Calibre

What is the difference between the two versions that causes the thumbnail cover not to be displayed?

P.S. It's a free ebook

Thanks

Stefano

[jhowell]

Originally Posted by stefano.sb

Hi, it's true! I agree with you jhowell! Attached there is a zip file with the two MOBI versions of the same ebook. The one with the file name ending with "NO CALIBRE.mobi" is the version NOT converted with Calibre

What is the difference between the two versions that causes the thumbnail cover not to be displayed?

I took a look at the MOBI files. According to the metadata the non-calibre file was produced using Mobipocket Creator version 4.2 on 2010-03-05.

The reason that file does not work correctly is that the cover image it contains is only 150 x 236 pixels. This is too small for the Kindle to produce a proper thumbnail image of the cover. (I do not know the actual minimum cover size needed. I suspect it varies by Kindle model and firmware.)

The cover in the working MOBI file is 317 x 500 pixels which is large enough to work properly.

[Hitch]

Originally Posted by jhowell

I took a look at the MOBI files. According to the metadata the non-calibre file was produced using Mobipocket Creator version 4.2 on 2010-03-05.

The reason that file does not work correctly is that the cover image it contains is only 150 x 236 pixels. This is too small for the Kindle to produce a proper thumbnail image of the cover. (I do not know the actual minimum cover size needed. I suspect it varies by Kindle model and firmware.)

The cover in the working MOBI file is 317 x 500 pixels which is large enough to work properly.

WOW, holy crapdoodle! (Crap, is it one of mine??? LOLOL...I don't think I've ever put a cover that small inside an ebook, but...that was a dozen years ago now.)

I'm getting flashbacks here.

Hitch

[JSWolf]

Originally Posted by Hitch

WOW, holy crapdoodle! (Crap, is it one of mine??? LOLOL...I don't think I've ever put a cover that small inside an ebook, but...that was a dozen years ago now.)

I'm getting flashbacks here.

Hitch

Maybe the cover is sized for a Blackberry.

[stefano.sb]

Originally Posted by jhowell

I took a look at the MOBI files. According to the metadata the non-calibre file was produced using Mobipocket Creator version 4.2 on 2010-03-05.

The reason that file does not work correctly is that the cover image it contains is only 150 x 236 pixels. This is too small for the Kindle to produce a proper thumbnail image of the cover. (I do not know the actual minimum cover size needed. I suspect it varies by Kindle model and firmware.)

The cover in the working MOBI file is 317 x 500 pixels which is large enough to work properly.

Thanks jhowell for the answer. The strange thing is that using the no Calibre ebook there is only one situation the thumbnail cover is show by my Kindle. See attached images.

But... it's ok the problem is the cover size

Stefano

[Hitch]

Originally Posted by stefano.sb

Thanks jhowell for the answer. The strange thing is that using the no Calibre ebook there is only one situation the thumbnail cover is show by my Kindle. See attached images.

But... it's ok the problem is the cover size

Stefano

No...maybe I'm wrong, but isn't one a PDOC (Personal Document) and the other a book?

Hitch

[stefano.sb]

Originally Posted by Hitch

No...maybe I'm wrong, but isn't one a PDOC (Personal Document) and the other a book?

Hitch

No, it's the same MOBI ebook (title "Tutti i pedoni del re") that is sideloaded via email to my kindle. It' s not converted with Calibre.

Stefano