Update file size

[sobriquet]

Hello,

In order to save disk space, i'm compressing my biggest ebooks with external tools.

However, Calibre doesn't update the file size. The only way in found to force Calibre to do it is by deleting and re-add the entry of the book. But then, i have to re-enter the other metadatas.

Do you know a better way to force Calibre to update the file size?

[BetterRed]

Try Quality Check (plugin)->Fix->Check and repair book sizes

Index of plugins

BR

[sobriquet]

Thanks you, i guess it should have done the job, but after having checked all the books, it does nothing and says "All book format sizes are correct" :/

[PeterT]

Just curious as to how much space savings are you seeing?

[kovidgoyal]

The size column in calibre shows the size of the largest format a book has, not that of individual formats.

[sobriquet]

@peterT
My database was 38 GiB before i started compressing my files. If i concentrate on biggest files, i think i can quickly reduce it to 30 GiB, and maybe 20 GiB if i spend more time. I reduced some epub from 150 MiB to 10 MiB, but it's quite the exception. Most of my work is on PDF files: depending on the file, i can reduce it from 2 to 10 times.

@kovidgoyal
yes, but still no It seems other people have the same trouble: https://www.mobileread.com/forums/sh...125428&page=68 (see nixsee's post). Maybe 'ill try to apply this patch later.

[DNSB]

Originally Posted by sobriquet

Hello,

In order to save disk space, i'm compressing my biggest ebooks with external tools.

However, Calibre doesn't update the file size. The only way in found to force Calibre to do it is by deleting and re-add the entry of the book. But then, i have to re-enter the other metadatas.

Do you know a better way to force Calibre to update the file size?

Manually doing this, my suggestion would be to open the containing folder for the book and copy the book to another location. Then use the remove books of a specific format to delete the book which leaves the information and then dropping the book back on the details pane.

Though looking at one of your later posts, I have trouble believing in reducing the size of an epub from 150MB to 10MB without turning the embedded images into crap. The only permitted compression methods in an epub are uncompressed and Deflate-compressed. Recompressing a 200+MB book (The Prophets of Smoked Meat by Daniel Vaughn) which was mostly images using the slowest Ultra option for Deflate compression took the file from 203MB (212,980,057 bytes) to 202 MB (212,616,217 bytes). Doing a lossless recompression of the images saved 26MB (399 image files) of of the original 207MB.

[DaltonST]

Job Spy has a tool to do exactly that.

[sobriquet]

@DNSB

Yes, it's a good idea, i think i'll do this, thank you!

Since in a big epub, most of the datas are Jpeg images, they are uncompressible lossless and the fastest compression mode of the whole file is almost as good as the slowest.

But we can recompress the images and play with the resolution. If the input images are high resolution and low compression, we can obtain small and very decent output images with the good balance of settings.

However, as i said, this 15:1 ratio compression is quite exceptional, and most of my epub are already very small. I should maybe point out that the images didn't contain text, only illustrations.