[GET] An Amazing Epub Compressor

[StillStanding]

I just shared an epub file "Cooking Light Smoothies and Snacks". The original file was 146MB, using the tool in the url I posted below, the file was compressed to an amazing 1.32MB!

I thought the file was probably corrupted, that there would be no way the file would be reduced that much. I checked the file before I posted it, and the quality was perfect. This is the first time I have used this tool, so I hope this result wasn't just a fluke.

Hope you find it useful

Code:

https://www.onlineconverter.com/compress-epub

[myme]

This could really create a lot of free space on my hard drive, as I have a ton of epub files there. Max reps for ya SS!!

[tlrademaker]

Thanks for the share!


max reps added

[Dulcinea]

Great tip;
https://www.onlineconverter.com/
offers SO much more, too!!
, SS!

[srw1958]

Seems like a great tool to use, I already compressed one epub file and it did it perfectly with no loss of quality. Max reps given.

[angelcrc7]

Excellent tool, many thanks and rep added, StillStanding :) Peace!

[MongoSmash]

It's a very good tool. I tried it on a few epubs - a couple failed entirely (don't know why) but most were compressed. I got compressions ranging from 60-90%, which is fantastic!

Near as I can figure, this tool works by:
1. unzipping the epub (epubs are actually zip files)
2. compressing the images using some mildly lossy image compression algorithm
3. zipping the epub again

For the vast majority of big epubs, the images are needlessly large, and the compression to lower resolution images doesn't really affect the usability of the ebook. I wouldn't use it on a picture book...

My big question - - does anyone know of a desktop software implementation of this? My upload speeds are terribly slow, making this a bit of a pain in the rear. I have SO many bloated epubs...

I could do it manually - copy epub, rename epub to zip, extract everything to a temp directory, use an image compressor like Caesium to compress the images, put the compressed images into the right directories in the "epub" structure, then zip it all up again and rename to epub. That is a lot of busy work.

Best Regards, Mongo

[grayzone]

I googled and found this:

ePub Optimizer
https://toxaris.nl/optimizer.html

Don't know how good it is though.

[MongoSmash]

(06-16-2019 05:14 PM)grayzone Wrote:  I googled and found this:

ePub Optimizer
https://toxaris.nl/optimizer.html

Don't know how good it is though.

Thanks Grayzone - I really appreciate your effort! I googled for a while and never came across this. I guess Google hates me...

I DL'd, installed and tested this app. My impressions:
Pro
+ small simple program
+ runs quite fast in a console window
+ easy to use - just drag and drop file onto desktop icon
+ works on all epubs I tried it on

Cons
- compresses only about 10%, compared to the above online service that compresses 60-90%
- sometimes replaces original file, sometimes leaves a newly named file in a random directory (I have a universal search program, so I could find it), so I guess you could say a little buggy

According to the Toxaris website, it works by playing with fonts and removing extraneous info (like metadata) from images. It doesn't actually compress the images, so overall compression is low. Interestingly, it further compressed the files I had already compressed with the online tool - removed around 200-500KB from those files. I didn't test a lot of them though - it might work better on others.

So - it's cool but still not what I was hoping for. If someone wants to trim down their epub a bit (optimization might be a better description) then this is a good tool. For real space savings, it doesn't quite hit the mark.

I guess I will continue searching for a program that does what the online program does - automatically compress the images in an epub using resolution downgrading and trimming borders. I know plenty about coding (in legacy languages like Fortran, LISP, APL, Pascal, Basic...in DOS-like environments) but I don't know anything about programs running/interacting in a Windows environment. I suppose at some point I should bite the bullet, find the time and learn C# or simlar. Time, time time...

Thanks again Mr. Grayzone!

Peace.

Mongo