290kb limitation in Sony readers

[bill_mchale]

Originally Posted by Sweetpea

I do split on chapters and other book parts. But this book only has three parts: map, text and family tree. There are no chapters at all (not even the paperbook has chapters). So, the main text is 1.4Mb large. And it's only the sony that has a problem with it...

1.4Mb of text and not a single chapter break? What author wrote this?

--
Bill

[bill_mchale]

Oh, here is a thought... does the limitation apply to LRF's? I know it is not quite as nice as ePub... but maybe it will work.

--
Bill

[astra]

Originally Posted by bill_mchale

Oh, here is a thought... does the limitation apply to LRF's? I know it is not quite as nice as ePub... but maybe it will work.

--
Bill

No. It doesn't apply to LRF and personally, I like LRF a lot more then ePub.

[bill_mchale]

Originally Posted by astra

No. It doesn't apply to LRF and personally, I like LRF a lot more then ePub.

Is that because of the fact that pre 900 Sony's won't justify the texts for ePubs? If so, I am with you. Every book I have read on my wife's Sony PRS-505 has been converted to LRF so I could have full justification. But if I decide to replace my broken reader with a 350 or 650, that won't be an issue anymore.

--
Bill

[astra]

Originally Posted by bill_mchale

Is that because of the fact that pre 900 Sony's won't justify the texts for ePubs? If so, I am with you. Every book I have read on my wife's Sony PRS-505 has been converted to LRF so I could have full justification. But if I decide to replace my broken reader with a 350 or 650, that won't be an issue anymore.

--
Bill

I also like TOC in LRFs.

Then...I can create very good LRF files myself. However, I have no idea how to create ePubs of the same quality, because there is no s/w such as Book Designer for ePubs, and s/w for ePubs require knowledge of html/xtml codding that I do not possess.

I will have to move over to ePub when I buy 650 though. There is no point in delaying it. I only have to read some 85 books in LRf that I have on my 505 at the moment first

[etienne66]

Originally Posted by Sergi

Is incredible this limitation. In this days, when you explain to someone that there's a limitation of 300kb in a new device, it's like if you were talking of something of the past.

I can understand the 300k as a recommendation, not as obligation. They can recommend no to use big files for performance questions.

Unfortunately I understand the constraint all too well. These ebook readers have a very limited CPU to conserve power. I've never noticed an ebook reader getting warm in my hands due to the CPU running. Whenever you load an ebook it has to process the entire "flow" before it can render a single page. If you have a book that has nothing but 290KB xhtml documents you will notice it takes a lot longer to load than one that has only 30KB documents.

These CPUs are typically running in the 200 to 500MHz and are much simpler than a similar processor used in a home computer. A 400 MHz Pentium III processor can compute more and faster than these CPUs, but they also take a lot more power. They have an L2 cache 512KB compared to the 16KB used in the ARM920T for the Pocketbook 302. A Pentium III can do 1,083 MIPS (Million Instructions Per Second) at 400 MHz. The ARM920T can do 555 MIPS at 400 MHz. And just to show an extreme, the Intel Core i7 Extreme Edition i980EE is rated at 147,600 MIPS at 3.3 GHz. The PRS-505 used the ARM920T at 200 MHZ so it would be around 222 MIPS.

I should also mention that the xhtml document may only be 290KB, but it takes a lot more RAM to render the document. You also need to consider that most of these devices only have 64MB to 128MB of RAM. Most modern computers come with at least 2GB.

I should say that I understand the constraint because I have run up against long delays in Windows while manipulating XML documents with my own programs. If you've been following the development of Sigil, you'll see he has had to give up treating entire books as a single flow for the same reason. This is on modern computers that you see a large delay. Admittedly editing has a lot more overhead than simply rendering the file, but it is magnified on these underpowered CPUs.

I agree that the limit is annoying, but this is due to the target CPU and not a limit of programming. CPUs have gotten better since Adobe started their Mobile Edition. You would think that they could at least double the limit by now.

Etienne66

[HarryT]

Originally Posted by etienne66

I thought it was a limitation of Adobe Mobile Edition and not particular to any specific reader. Is there any ebook reader using the Adobe engine that does not have this limitation?

Etienne66

Take your pick. Pretty much none of the other ADE readers have this limitation.

[bill_mchale]

Originally Posted by astra

I also like TOC in LRFs.

Then...I can create very good LRF files myself. However, I have no idea how to create ePubs of the same quality, because there is no s/w such as Book Designer for ePubs, and s/w for ePubs require knowledge of html/xtml codding that I do not possess.

I will have to move over to ePub when I buy 650 though. There is no point in delaying it. I only have to read some 85 books in LRf that I have on my 505 at the moment first

Doesn't the 650 still support LRF?

--
Bill

[etienne66]

Originally Posted by Sweetpea

My BBMini can read that same book without problem and so can my ProMedia.

That is interesting. From what I can find those are using Adobe Mobile Edition, but Adobe has not updated their "Best Practices Guide" since 2008. It still says, "Note that Adobe Digital Editions has the following limitations when running on a mobile device. If these limits are not adhered to, EPUB files will not work on supported mobile devices including the SONY® Reader Digital Book.

Image Size: 10MB uncompressed.
XHTML/DTBook file size: 300k uncompressed/100k compressed."

You'd think if Adobe had increased the flow size, they would have updated this document.

Etienne66

[bill_mchale]

Originally Posted by etienne66

That is interesting. From what I can find those are using Adobe Mobile Edition, but Adobe has not updated their "Best Practices Guide" since 2008. It still says, "Note that Adobe Digital Editions has the following limitations when running on a mobile device. If these limits are not adhered to, EPUB files will not work on supported mobile devices including the SONY® Reader Digital Book.

Image Size: 10MB uncompressed.
XHTML/DTBook file size: 300k uncompressed/100k compressed."

You'd think if Adobe had increased the flow size, they would have updated this document.

Etienne66

Not necessarily. Adobe might well recognize that there are quite a few readers out there that still have this limitation. They know Sony, perhaps the most popular ebook reader outside the United States has this limitation and that earlier versions of other readers do as well. You can't count on customers to take the initiative to upgrade their own firmware. Therefore, fix the limitation for the future, but still recommend adhering to the limits.

--
Bill

[etienne66]

Originally Posted by bill_mchale

Not necessarily. Adobe might well recognize that there are quite a few readers out there that still have this limitation. They know Sony, perhaps the most popular ebook reader outside the United States has this limitation and that earlier versions of other readers do as well. You can't count on customers to take the initiative to upgrade their own firmware. Therefore, fix the limitation for the future, but still recommend adhering to the limits.

--
Bill

You're probably right. Still books with smaller flows do work faster. The problem comes in when you have a really large book with few chapters, like Sweatpea.

I saw on the Adobe forum that one person had problem with his OPF file being too big because he had a large number of photographs, over 10,000. The OPF was over the 300KB limit and failed the EpubPreflight.

I guess the only way they are going to be able to change it is to start a version number on it. Currently epub is as 2.01 and the IDPF are working on 3.0. So when Adobe starts supporting 3.0 maybe we'll start seeing an supports epub 3.0 logo or something.

I didn't like the way the IDPF sort of abandoned their old website Daisy.Org and snuck over to code.google.com/p/epub-revision/ without putting a note on the old website. I found the link buried in a message on their tracker.

Etienne66

[Sweetpea]

Originally Posted by bill_mchale

1.4Mb of text and not a single chapter break? What author wrote this?

--
Bill

Wilbur Smith. Not sure about all his books, but his Egyptian books are all chapterless. And I don't want to force page breaks in the text, which will happen if you split the text. At least, in mobipocket. And I use my epubs to create the mobipockets. And the mobipockets I use on my WinMobile devices and the Kindle.

[astra]

Originally Posted by bill_mchale

Doesn't the 650 still support LRF?

--
Bill

650 supports LRF. I am planning to use ePub when I buy 650, but I have to finish reading LRF books that I have already created and uploaded to 505. I will read them on 650 of course. It is going to delay my reluctant transfer to ePubs Sorry for not making my thoughts clear

[bill_mchale]

Originally Posted by astra

650 supports LRF. I am planning to use ePub when I buy 650, but I have to finish reading LRF books that I have already created and uploaded to 505. I will read them on 650 of course. It is going to delay my reluctant transfer to ePubs Sorry for not making my thoughts clear

But why worry about switching to ePub if you like LRF better? Granted, if you are dealing with DRM books it is not an option unless you strip the DRM, but otherwise, why not stick with what you like?

Personally, I would stick with the PRS-505 if it was mine and not my wife's. Its not perfect (But no reader is), but its a pretty nice reader . Depending on which reader I get to replace my broken Jetbook, I might still keep the PRS-505... it depends on what the wife likes more. She doesn't like touch screens though, and that means that if I get the newer Sony's or the Nook it will be for me... and I am just not sure how reliable the Kobo's are (The Pocketbooks are nice... but kind of pricey and I am not sure I want to go with a brand where I can't look at the device first.).

--
Bill

[Pablo]

Originally Posted by astra

I also like TOC in LRFs.

Then...I can create very good LRF files myself. However, I have no idea how to create ePubs of the same quality, because there is no s/w such as Book Designer for ePubs, and s/w for ePubs require knowledge of html/xtml codding that I do not possess.

I will have to move over to ePub when I buy 650 though. There is no point in delaying it. I only have to read some 85 books in LRf that I have on my 505 at the moment first

I do all my editing in Book Designer (Book Title, Book Author, Titles, Subtitles, Notes and links, page breaks, etc). Then I use my HTML02HTML utility to convert to HTML with CSS and after that I import into Sigil 2.0. In Sigil I just split chapters with a single command, create the TOC and save as ePub. I don't spend more than 2 minutes inside Sigil, unless I want to embed a font, in which case it takes another 2 minutes. The resulting ePub is OK for me.
Knowledge of html/xhtml is not really necessary.