Difference between MOBI and AZW3

[maurices5000]

Ok, i notice that when i convert my ePUB books to AZW3, my books look exactly like the original ePUB books. But when i convert them to MOBI, i lose formatting. Why is that? Is the issue with MOBI, Calibre or my setup?

I've been happy with Mobi for quite a while but I do wonder if i'd enjoy my ebooks better if i could view them as intended in the original ePUB format.

In MOBI none of the images float alongside the text. Borders and shading disappear. These borders are there to show that the imformation is supplementary or to distinguish between sections.

Does MOBI not support these? I have Calibre set up incorrectly? Or does Calibre not support this for the MOBI format?

Thanks guys! Just trying to understand.

[crich70]

I think AZW3 is just a way of coding Mobi books so that they can't just be converted to epub or other formats. Part and parcel of the DRM junk. I could be wrong though. As for why epubs come out looking bad when converted to mobi I'm not sure. Were they DRM free books? If not then it might be a DRM caused problem. And not much can be said about DRM on MR.

[itimpi]

The 'original' mobi format was relatively restricted in the formatting it allowed. More recently Amazon introduced the azw3 format that is much closer to epub (it is based on the epub standard) and has richer formatting support. The azw3 format is so close to epub that it is relatively easy to extract it as an epub.

To confuse things further Amazon introduced the 'new' mobi format that contain two copies of the book - one in azw3 format and the other in the original mobi format. The idea is that the reader uses the azw3 version of it supports azw3 and the mobi version if not.

[jgaiser]

Originally Posted by crich70

I think AZW3 is just a way of coding Mobi books so that they can't just be converted to epub or other formats. Part and parcel of the DRM junk.

Huh? No. I'm not an expert on AZW3, but I believe it's an Amazon specific wrapper around an epub file. And AZW3 files do very nicely convert to many other formats, including epub.

[Rizla]

mobi is a more primitive format than epub, so I guess with things like images and advanced formatting, you might get problems going from epub -> mobi. For that matter, you'd probably get problems going from az3 to mobi.

I'm not sure of the best way to deal with it. You could try converting to an intermediate format first, maybe to pdf or .doc or something, then convert that to an epub. It sounds bizarre, but it might work.

In fact, try converting the .mobi to .htmlz, then convert the .htmlz to .epub.

[maurices5000]

Thanks guys good information. Rizla, I'll try your suggestions. I've thought about doing something similar to what you said but i wasn't sure it would work and did not know enough about the formats. For example, I'm not sure how well DOC files support internal links.

[AlexBell]

I think you will find that it is impossible to get good results converting complex ebooks from azw3 or ePub formats to mobi.

Mobi was loosely based on HTML 3.2, which is now about ten years old, and is very much less flexible and less powerful than the XHTML in ePub ebooks or the HTML5 and CCS3 in az3 ebooks.

To use rather crude analogies one wouldn't expect to get a good picture if one viewed a video film produced today on one of the first TVs sets developed, or get a good ride if one put the first petrol produced into a modern day car.

[speakingtohe]

As others have said, mobi is less sophisticated in terms of font choices, font sizes, and advanced graphic features.

It does have it's advantages at times, but does not do anything fancy. I actually admire Amazon for leaving it alone while continuing to support it. (I don't have a kindle but my mother has)

Helen

[AverySays]

Originally Posted by AlexBell

I think you will find that it is impossible to get good results converting complex ebooks from azw3 or ePub formats to mobi.

It is not impossible. I have done it several times.

[theducks]

Originally Posted by AverySays

It is not impossible. I have done it several times.

I think you missed the word 'Complex'

Mobi and complex are mostly exclusive.

Mobi seems to need nested BQ just to reliably center

[speakingtohe]

Define complex for me.
I usually get good results converting epubs to mobi. TOC good, Images good, formatting good. Embedded fonts not good, but gone, which is sometimes why I do it.

I only convert to mobi and back when the book is unreadable on the reader as is. Kobo readers mainly. The books displayed fine on my Sonys but unpleasantly on my Kobos.

As most of the problem books were/are older formats converted to epubs, there were seldom embedded fonts. Just quadruple line spacing and 2 inch margins etc. The Sonys handled them fine, but at one time I actually wanted to use my Kobos.
Converting to mobi and back gave me a book that looked close to identical on both devices. This seemed to be a good result as that was my goal. And centering generally worked, or else it was aligned left which was good enough for me.

Helen

[theducks]

Originally Posted by speakingtohe

Define complex for me.

Helen

What I do is simple/basic

Way more than simple/standard Paragraph indents
How about 3 men in a boat (found in the MR Library).

Charts, Hanging indents.

A lot can be worked around, but a simple conversion, no.

(I use AZW3 for my use, even then, my nice dropcaps on my PEz (MRSDK) come out with to much space below, lost the alignment.

OTOH embedded font do work

[DaltonST]

Amazon supports .mobi because if they did not, they would be sued by everyone who bought .mobi books for use by MobiPocket at http://www.mobipocket.com/ many years ago, including me. I read them on my PalmOS devices, plus my Win98/Me PCs.

Amazon bought MobiPocket, and also the .mobi format, so they would have little competition when they got into selling ebooks. Amazon did everything it could get away with to kill off .mobi in favor of its own formats.

The Federal Trade Commission would have viewed their actions as anti-competitive and on the road towards monopolistic if they had dropped support for .mobi.

Personally, I converted my .mobi books to epubs (via Calibre) years ago.



DaltonST

[JSWolf]

Originally Posted by speakingtohe

Define complex for me.
I usually get good results converting epubs to mobi. TOC good, Images good, formatting good. Embedded fonts not good, but gone, which is sometimes why I do it.

Before you dump embedded fonts, you really need to stop and make sure the fonts are not needed. Like sometimes the fonts are embedded so the correct characters are displayed because the default font doesn't do it. Also, sometimes the embedded fonts are used to offset/highlight something and that you lose that if you remove them. There are more reasons for embedded fonts then just to display a certain font.

I only convert to mobi and back when the book is unreadable on the reader as is. Kobo readers mainly. The books displayed fine on my Sonys but unpleasantly on my Kobos.

As most of the problem books were/are older formats converted to epubs, there were seldom embedded fonts. Just quadruple line spacing and 2 inch margins etc. The Sonys handled them fine, but at one time I actually wanted to use my Kobos.
Converting to mobi and back gave me a book that looked close to identical on both devices. This seemed to be a good result as that was my goal. And centering generally worked, or else it was aligned left which was good enough for me.

Sometimes those display issues can be fixed with some simple CSS editing. Calibre's eBook editor will allow you to fix up those eBooks so they will look good on a Kobo Reader. The best way to do it is to have a look at the CSS and XML before another conversion and see how easy it might be to fix things.

[JSWolf]

Originally Posted by DaltonST

Amazon supports .mobi because if they did not, they would be sued by everyone who bought .mobi books for use by MobiPocket at http://www.mobipocket.com/ many years ago, including me. I read them on my PalmOS devices, plus my Win98/Me PCs.

Amazon could have killed off Mobi and that would have been the end of it. Suing Amazon over that would have been a waste of time. Sony was able to shoehorn ePub into a PRS-500 and I think Amazon could have shoehorned AZW3 into the older KIndles given that they have better harware specs then did the 500.

Amazon bought MobiPocket, and also the .mobi format, so they would have little competition when they got into selling ebooks. Amazon did everything it could get away with to kill off .mobi in favor of its own formats.

Amazon bought Mobipocket so they could have an eBook format that they fully owned. It had nothing to do with killing off competition.

The Federal Trade Commission would have viewed their actions as anti-competitive and on the road towards monopolistic if they had dropped support for .mobi.

Amazon has killed off Mobipocket (the version sold by Mobipocket.com). The FCC doesn't care because it's an old obsolete format and it's not really used much.