Images Question - Help

[Bren10]

I have an epub,it's a maths book.

It contains 2088 images.It loads slow.

So what i did was,create a new simple epub that has one page,but i copied the 2088 images into this new epub folder and it took the same time to load as the other one(slow)

My question : Does the amount of images have an effect on load time?Because i have a similar book that has a 75 image folder but it is the same in size collectively as the image folder with the 2088 images.

But the 75 image folder epub loads fast.

[JSWolf]

I know this doesn't answer your question, but are you planning on selling this eBook and if so, are the 2088 images of high enough resolution to be seen on a high resolution eInk screen without bother?

[pdurrant]

Originally Posted by Bren10

I have an epub,it's a maths book.

It contains 2088 images.It loads slow.

So what i did was,create a new simple epub that has one page,but i copied the 2088 images into this new epub folder and it took the same time to load as the other one(slow)

My question : Does the amount of images have an effect on load time?Because i have a similar book that has a 75 image folder but it is the same in size collectively as the image folder with the 2088 images.

But the 75 image folder epub loads fast.

Then clearly the slowness in loading is to do with the number of images, not their size.

You don't mention what device or software you're using that is slow with this ePub. It's entirely possible that different software will load more quickly, as it seems that this software loads or at least verifies all the images in the document on startup, rather than just when needed.

[Bren10]

Originally Posted by pdurrant

Then clearly the slowness in loading is to do with the number of images, not their size.

You don't mention what device or software you're using that is slow with this ePub. It's entirely possible that different software will load more quickly, as it seems that this software loads or at least verifies all the images in the document on startup, rather than just when needed.

I was using calibre on a I7 dell precision 2.8ghz,8gig ram laptop, i think you are right,it probably verifies all the images first.

[pdurrant]

Originally Posted by Bren10

I was using calibre on a I7 dell precision 2.8ghz,8gig ram laptop, i think you are right,it probably verifies all the images first.

Calibre is not really designed as an efficient ePub viewer. I'd advise testing on actual devices.

[Divingduck]

Originally Posted by Bren10

I have an epub,it's a maths book.
... So what i did was,create a new simple epub that has one page, ....
But the 75 image folder epub loads fast.

Yes, that is the point.

In addition to what was already mentioned, the part above is an additional problem for EPUB-Reader. A e-reader try to cache as much as possible from a accessed file inside a book. In your special case the e-reader is never able to do that and is all the time busy with cache activities. If you put all pictures in one page/file the e-reader will operates always on its limits.
If you like to generate a book with a huge amount of pictures, reduce the resolution to what is reasonable and group pictures together in smaller pices like chapter files. If it is a commercial project, you can maybe offer a download link for high quality pictures and/or a second edition for devices with more powerful hardware.

[Bren10]

Thank you very much guys for the feedback, i was just trying to get my head around the loading process ,thanks for helping me better understand it.

[theducks]

Note: How the Sections are constructed also affects load on some devices.

Older 'Paged' display typically loaded the current Section.
Smooth Scroll devices have to load the entire book (I think the Calibre Viewer falls here)

Many images in a single file, all have to load (render) with that Section.
Wrap the <img tag in messy (nested) code and it gets slower.
Lean and Mean code is