Mobi format limitations

[wmaurer]

Hi all

I've had a recent exchange with Taylor&Francis about getting their books converted to Mobi format. In particular, I'm interested in their language books as I'm learning Spanish and German. The range of books that they available in Mobi format is relatively small compared to the total number of e-books in other formats.
http://www.ebookstore.tandf.co.uk

I have sent them an email asking (urging) them to offer more books in Mobi format. This is the response I got:

Regarding the titles not available in Mobi format, there is little we can do I'm afraid. For various technical reasons, it is not always feasible to convert all our ebooks into Mobi format. That particular fomat has limitations in terms of display and layout which prevent some books from being rendered poroperly. If this means the customer experience is degraded, we prefer not to sell the title in quesiton (as opposed to charging full price for something which is less than satisfactory to the customer).

This is why 20,000+ titles are available in DX format (online access), but only a subset is available for all other formats.

I'm not sure what DX format is, but if I can't read it on my Cybook, I'm not interested. In fact I can't even read it on my computer as I run Linux, not Windows.

Is Mobi format really that deficient? How does it compare to Microsoft Reader? What can I say to Taylor&Francis to convince them that it's worth publishing in Mobi format? I've already mentioned the Kindle market.

Right now I'm feeling a bit despondent about my investments in ereader hardware and in ebooks, as it seems that I can only find about a third of the books I want in the format that I use.

-Wayne

[llasram]

Originally Posted by wmaurer

Is Mobi format really that deficient? How does it compare to Microsoft Reader? What can I say to Taylor&Francis to convince them that it's worth publishing in Mobi format? I've already mentioned the Kindle market.

I'm currently working on Mobipocket generation for Calibre, and oh yeah -- it's utterly abysmal. The problem is two-fold:

First, the actual capabilities have many and frequently eccentric limitations. Text may only be displayed in seven different font-sizes, only two of which are smaller than normal text. Blocks of text can never have a greater than normal margin on their right side. Left margins can only be specified in 1em increments. Text can only have a hanging indent if it has no left margin. Text cannot flow around images taller than one line of text. Image sizes cannot be scaled with font size. In some -- but not all -- Mobipocket renderers, text with a left margin changes that margin value per line based upon the font-size at which point the preceding line-break occurred. Many measures, such as the indent of a hanging indent, cannot be specified in ems. Text cannot be displayed in a monospace font. Tables display wildly differently on different Mobipocket renderers, especially tables which cross more than one screen. And I'm sure I'll find many more once I finish oeb2mobi and people start submitting bugs.

Second, you only get the full range of Mobipocket's formatting capabilities if you have markup written to use Mobipocket's non-standard, extended, and under-documented implementation of HTML 3.2. The rest of the world -- including the Microsoft LIT format -- has moved on, and is using some form of HTML 4.0 or XHTML 1.x along with CSS. Converting standards-compliant markup to Mobipocket's markup is a difficult process. This problem is not simplified by the state of the Mobipocket-provided tooling (mobigen) which frankly does an abysmal job of converting even reasonably complexly formatted HTML+CSS into something presentable in Mobipocket. Anything like a complex table, side notes, side bars etc will pretty much need to be converted manually to a linear flow in order to be legible.

Originally Posted by wmaurer

Right now I'm feeling a bit despondent about my investments in ereader hardware and in ebooks, as it seems that I can only find about a third of the books I want in the format that I use.

If the books you want are sold in other formats, you can always buy them in those formats and convert yourself. Calibre should have Mobipocket-generation in the next month or so and there are several other existing tools which will do the job.

[DaleDe]

The database format does have a lot of limitations when it comes to rendering technical books. For example you can't switch part of the text use mono-spaced fonts which prevents control of some spacing. There is no CSS support in the document format although the creation program has some support and attempts to translate it. In addition there are many limitations caused by the implementation of the various readers. There is a wiki entry called MOBI that begins to document some of these limitations. Eventually it will have even more.

Dale


Dale

[delphidb96]

Originally Posted by llasram

I'm currently working on Mobipocket generation for Calibre, and oh yeah -- it's utterly abysmal. The problem is two-fold:

First, the actual capabilities have many and frequently eccentric limitations. Text may only be displayed in seven different font-sizes, only two of which are smaller than normal text. Blocks of text can never have a greater than normal margin on their right side. Left margins can only be specified in 1em increments. Text can only have a hanging indent if it has no left margin. Text cannot flow around images taller than one line of text. Image sizes cannot be scaled with font size. In some -- but not all -- Mobipocket renderers, text with a left margin changes that margin value per line based upon the font-size at which point the preceding line-break occurred. Many measures, such as the indent of a hanging indent, cannot be specified in ems. Text cannot be displayed in a monospace font. Tables display wildly differently on different Mobipocket renderers, especially tables which cross more than one screen. And I'm sure I'll find many more once I finish oeb2mobi and people start submitting bugs.

Second, you only get the full range of Mobipocket's formatting capabilities if you have markup written to use Mobipocket's non-standard, extended, and under-documented implementation of HTML 3.2. The rest of the world -- including the Microsoft LIT format -- has moved on, and is using some form of HTML 4.0 or XHTML 1.x along with CSS. Converting standards-compliant markup to Mobipocket's markup is a difficult process. This problem is not simplified by the state of the Mobipocket-provided tooling (mobigen) which frankly does an abysmal job of converting even reasonably complexly formatted HTML+CSS into something presentable in Mobipocket. Anything like a complex table, side notes, side bars etc will pretty much need to be converted manually to a linear flow in order to be legible.



If the books you want are sold in other formats, you can always buy them in those formats and convert yourself. Calibre should have Mobipocket-generation in the next month or so and there are several other existing tools which will do the job.

The font size limitation must be a limitation on the Sony because I've got (only one font or size selectable at any time) FOURTEEN installed fonts and EACH font supports TWELVE sizes from about 6pt to 36pt on my Cybook. Now I'll grant that the Mobi implementation on the Cybook doesn't support multiple fonts or multiple sizes within an ebook, but one still has the ability to use bold and italics.

Derek

[llasram]

Originally Posted by delphidb96

The font size limitation must be a limitation on the Sony because I've got (only one font or size selectable at any time) FOURTEEN installed fonts and EACH font supports TWELVE sizes from about 6pt to 36pt on my Cybook.

The Sony Reader doesn't support Mobipocket at all -- and even if it did, I'm talking about limitations of Mobipocket as a format.

Originally Posted by delphidb96

Now I'll grant that the Mobi implementation on the Cybook doesn't support multiple fonts or multiple sizes within an ebook, but one still has the ability to use bold and italics.

I doubt "at all" for sizes -- I'm sure it supports the seven pre-defined, base-relative sizes the Mobipocket format supports.

[wallcraft]

Originally Posted by llasram

Text may only be displayed in seven different font-sizes, only two of which are smaller than normal text.

This is standard for HTML, and is still true for CSS absolute-size (although for CSS "medium" is the center value of 7). See CSS 2.1, 15.7 Font size. Since the user can usually set the default font size, this does not limit MobiPocket Reader to seven sizes. However, in some cases the device/Reader has fewer than 7 font sizes available and then some of the 7 font sizes will be mapped onto the same displayed font size.

In Extra Large Print Kindle ebooks, I point out an example of a 7-th font size on a Kindle that only has options for 6 default sizes.

[llasram]

Originally Posted by wallcraft

This is standard for HTML, and is still true for CSS absolute-size (although for CSS "medium" is the center value of 7). See CSS 2.1, 15.7 Font size. Since the user can usually set the default font size, this does not limit MobiPocket Reader to seven sizes. However, in some cases the device/Reader has fewer than 7 font sizes available and then some of the 7 font sizes will be mapped onto the same displayed font size.

It's "standard for HTML" for HTML 3.2, which hasn't been "standard" since HTML 4.0 was published in 1997. And although CSS only defines 7 "absolute" font sizes, it's possible to use cascade rules to specify any proportion of one of those sizes as a base.

My main point with that is that it isn't possible to replicate something like The Mouse's Tale in Alice in Wonderland, which requires many, many more than 7 discrete font sizes within a single e-book.

[delphidb96]

Originally Posted by llasram

The Sony Reader doesn't support Mobipocket at all -- and even if it did, I'm talking about limitations of Mobipocket as a format.



I doubt "at all" for sizes -- I'm sure it supports the seven pre-defined, base-relative sizes the Mobipocket format supports.

Okay. In 'general' that may be the case. Howsomeever, if you'll look at the image I just took of my Cybook in an ebook, with the Font Size selection menu up and displayed, you'll be able to count twelve (12), that's right, TWELVE, distince font sizes for the particular font I have up. I could show you the same set of twelve sizes for any of the over fourteen fonts I have installed, but I'm not going to waste any further time on this tonite.

Derek

P.S. I'll grant that the smallest font size is too small to be comfortably readable for me, even when I'm wearing my reading glasses, and the largest just doesn't leave all that many words on each 'page' displayed, but it's quite a range of font sizes.

[Andybaby]

Originally Posted by delphidb96

Okay. In 'general' that may be the case. Howsomeever, if you'll look at the image I just took of my Cybook in an ebook, with the Font Size selection menu up and displayed, you'll be able to count twelve (12), that's right, TWELVE, distince font sizes for the particular font I have up. I could show you the same set of twelve sizes for any of the over fourteen fonts I have installed, but I'm not going to waste any further time on this tonite.

Derek

P.S. I'll grant that the smallest font size is too small to be comfortably readable for me, even when I'm wearing my reading glasses, and the largest just doesn't leave all that many words on each 'page' displayed, but it's quite a range of font sizes.

all ebook readers should pick up adjustable fonts and sizes.
Though i convert all my books, so i got the font and size i want (Gerogia, Size 7, read on L on my PRS-700 which is comfortable. but honestly M is too small and XL is too big let alone S and XXL)

[mtravellerh]

I sincerely doubt that the technical limitations of the Mobi pocket really are at the base of Taylor & Francis's problem.

The real problem, in my eyes, is the somewhat strange perception editors do have of e-books and e-book formats.

Don't get me wrong, also I don't understand even half of llasram's technospeak, I concur with him in that mobi is a fairly limited and not very up-to-date format.

But editors think that an e-book version, regardless what format of e-book, has to be just like the pbook. Of course, that is a complete and utter misunderstanding of the concept of e-books as they represent pretty much a new form of media and paper books cannot be transferred to e-books one to one, Basta.

E-book formats are still in evolution and some offer more layout possibilities than others, some are more flexible regarding its software platforms while others are more rigid. Rule of thumb: The more a format is rigid concerning hard- and software, the better the layout possibilities.

If T&F is clinging to its layout or features a lot of technical books with tables, formulas and the like, their decision may be understandable but shows that the concept of interchangeable hard- and software platforms hasn't reached them yet.

[Vesper]

Originally Posted by llasram

... Text cannot be displayed in a monospace font...

Beg to differ! You have to use those mobipocket-only tags but you can. It has even 4 (four) of them available - kbd, tt, code and samp. Text is rather pale and sickly looking but it's there. Cybook can recognize them all.

DrS

[llasram]

Originally Posted by Vesper

Beg to differ! You have to use those mobipocket-only tags but you can. It has even 4 (four) of them available - kbd, tt, code and samp. Text is rather pale and sickly looking but it's there. Cybook can recognize them all.

Oh, good for the Cybook . I was basing my claim off the fact that the Mobipocket Desktop Reader doesn't display text within those tags any differently from other text.

[llasram]

Originally Posted by delphidb96

Okay. In 'general' that may be the case. Howsomeever, if you'll look at the image I just took of my Cybook in an ebook, with the Font Size selection menu up and displayed, you'll be able to count twelve (12), that's right, TWELVE, distince font sizes for the particular font I have up.

Sure, you -- as a user -- have many, many options for the base font size you can configure your reader software / device to use. An e-book creator creating a Mobipocket book can only within the book specify text at seven discrete font sizes. If the e-book creator wants text within a single book to have text at three different sizes smaller than the base font size, then they're out of luck.

Originally Posted by delphidb96

I could show you the same set of twelve sizes for any of the over fourteen fonts I have installed, but I'm not going to waste any further time on this tonite.

But somebody is WRONG on the INTERNET!

[wallcraft]

Originally Posted by llasram

An e-book creator creating a Mobipocket book can only within the book specify text at seven discrete font sizes. If the e-book creator wants text within a single book to have text at three different sizes smaller than the base font size, then they're out of luck.

There is a work around - refine the base font size to a number above 3 (I suppose this is actually overriding the default in every paragraph, rather than redefining the default). This is what the large print Kindle ebooks do (see post #6 above). They actually define the default to be 7, but it would be better to have used 4 or 5. The side effect of this is that the base font will be larger than expected by the reader (larger than in other ebooks). So they may have to reset their default font size for these ebooks.

[llasram]

Originally Posted by wallcraft

There is a work around - refine the base font size to a number above 3 (I suppose this is actually overriding the default in every paragraph, rather than redefining the default). This is what the large print Kindle ebooks do (see post #6 above).

Oh my. Oh dear. I think some part my brain intentionally resisted understanding what you'd meant before. Oh the crimes against technology!