why are some epub files so big?

[Bookripper]

Ok, I have an epub book, opened with Sigil in front of me. the book is 2,4 MB big. it has 10 pics in it (thumbnail size or a bit bigger, +- 15 KB each), the cover is 40 KB. There are about 800 pages. no video, audio or misc attachments.

Normally a book this size would be around 700 KB. But it's almost 4 times as big. Does anyone know what causes this? Or how I can shrink them :-)

thanks, Ripper

[mbovenka]

Originally Posted by Bookripper

Ok, I have an epub book, opened with Sigil in front of me. the book is 2,4 MB big. it has 10 pics in it (thumbnail size or a bit bigger, +- 15 KB each), the cover is 40 KB. There are about 800 pages. no video, audio or misc attachments.

Normally a book this size would be around 700 KB. But it's almost 4 times as big. Does anyone know what causes this? Or how I can shrink them :-)

thanks, Ripper

Custom fonts?

[Bookripper]

Originally Posted by mbovenka

Custom fonts?

Yeah, that must be it. I didn't know that took up so much space though...

I got here "casino royale" by Ian Fleming. 300 pages, no pictures, and its 1.7 MB. But it has 15 different Fonts....

[fjtorres]

In my Windows folder I have 495 fonts of which 30 run from one megabyte to *thirty* megabytes. Times New Roman runs 809KB. The smallest non-decorative serif font in there is Toledo-regular at 50Kb. I wonder if the hinting is reponsible for the larger sizes...

[Ripplinger]

And yet another reason to want to strip DRM from a book so you can get rid of the embedded fonts. I've purchased a few books that went crazy with images as well, where they have the same exact cover image in 5 different sizes... makes zero sense, and I'll open those up as well and get rid of the unnecessary images that are just wasting space on my reader.

But embedded fonts for me is something that I will always immediately get rid of.

[theducks]

Originally Posted by Bookripper

Ok, I have an epub book, opened with Sigil in front of me. the book is 2,4 MB big. it has 10 pics in it (thumbnail size or a bit bigger, +- 15 KB each), the cover is 40 KB. There are about 800 pages. no video, audio or misc attachments.

Normally a book this size would be around 700 KB. But it's almost 4 times as big. Does anyone know what causes this? Or how I can shrink them :-)

thanks, Ripper

All those other reasons
And
Messy code (eg. Word cruft), Anchors at every paragraph (can happen when converting from so HTML formatted for Browser/Java navigation (Baen for example)

[Joykins]

yes, there can be hideously cluttered html living underneath that epub. I have cleaned some up backstage...

[Bookripper]

Originally Posted by Ripplinger

And yet another reason to want to strip DRM from a book so you can get rid of the embedded fonts. I've purchased a few books that went crazy with images as well, where they have the same exact cover image in 5 different sizes... makes zero sense, and I'll open those up as well and get rid of the unnecessary images that are just wasting space on my reader.

But embedded fonts for me is something that I will always immediately get rid of.

Exactly, it's just fat in your Ereaders memory.
So I can just delete them and everything goes to a standard font? Or do need to replace them with other fonts?

[medard]

For me the main reason for switching from Kindle to Sony was that digital books got really large in file size in the past months.

A year ago 300-500 kb were normal, and then 1 GB internal storage are OK.

But now the average book has 2 MB, some are even 4-16 MB. So you need external storage via SD card, at least I do.

[Chi Cygni]

Originally Posted by Bookripper

Exactly, it's just fat in your Ereaders memory.
So I can just delete them and everything goes to a standard font? Or do need to replace them with other fonts?

When I come across fat epub I convert it to mobi and back to epub. Immediate diet and Opus opens book much faster. Not elegant solution, so I've heard, but it works.

[snarkophilus]

Originally Posted by Chi Cygni

When I come across fat epub I convert it to mobi and back to epub. Immediate diet and Opus opens book much faster. Not elegant solution, so I've heard, but it works.

Are you doing that conversion with Calibre? If so, it's much easier to use kiwidude's wonderful Modify ePub plugin to remove embedded fonts. Multiple conversions may lead to funny changes in formatting or other unintended changes.

Cheers,
Simon.

[samhy]

Originally Posted by medard

For me the main reason for switching from Kindle to Sony was that digital books got really large in file size in the past months.

A year ago 300-500 kb were normal, and then 1 GB internal storage are OK.

But now the average book has 2 MB, some are even 4-16 MB. So you need external storage via SD card, at least I do.

I'm a new Kindle ebooks buyer, but I was really surprised by the size of the files Some epubs are heavy too, depending on the formatting, but the ones from Amazon are way heavier than them
I'll try to convert two or three books this week and I'll see if the size shrinks a little by itself. I still can use to look inside and clean things up.

I think that Amazon puts different picture sizes so the device will find the one right for it without breaking a sweat. I can't tell if in the end that's for the best (doesn't push the processor too far) or for the worst (very heavy files are resources consuming too).

[Ripplinger]

Originally Posted by Bookripper

Exactly, it's just fat in your Ereaders memory.
So I can just delete them and everything goes to a standard font? Or do need to replace them with other fonts?

I open up the epubs in Sigil and delete the fonts themselves. Then I also go through the stylesheet.css file and delete all references to "font-family:xxxx" where all the special fonts are called. You don't change anything else about the epub that way, the formatting and code stay the same. If there's excess images like I said, various sizes of the same image, I delete those too and the pages that reference them, they're just about always on their own page. Then it all reverts to default font uses, or if you have a hack on your reader that allows more fonts, you can freely change to any font you want.

I also don't like when they include several chapters or images from another book, another waste of space although that part is usually minimal... I'll never ever read them that way. Either I'm interested in the book and will buy it or not, reading the opening chapters, where it's usually the slowest-moving of the storyline, will never make me want or not want a book. The images though can be a pain, I've seen some books with a multitude of smaller images for almost every book an author has written... waste of space as well as annoying to me and I remove those pages and images as well.

Conversions as said can help, but can you sometimes end up with undesired results. The Modify ePub plugin can also be tried, but it's not always 100% foolproof, I've run across some books where it didn't remove the font. Sigil is so simple to use and you're in total control of what gets changed or not.

Mobi files are always larger in file size than the identical epub. A lot of times the mobi files are created in both new and old mobi formats, which is actually the 2 versions in one file. If I convert an epub into mobi, I always select the older format, which is the smaller size and will be compatible on all Kindles.

[Canorka]

I don't mind embedded fonts so much; in my experience (99% of the time Charis SIL) they don't contribute to huge file sizes. Highish res photos though... I have a couple of ebooks that are 60-70mbs. A tad excessive...

[Freeshadow]

And because there are cases where extra fonts are needed - that was one of the reasons I said font subsetting is a must for good tailored epubs.