Hi
This is a request for information about djvu size advantage and creation.
I read that many organizations use djvu for the storage of electronic documents because of its size saving features. I did a few tries to check it. As I am a Linux user, I used the handy
pdf2djvu conversion tool with a 300 dpi resolution. I got the following results:
- a 7.2 MB pdf became a 13.3 MB djvu. It contains 99.8% text and one cover image.
- a 26.5 KB pdf black and white image (300 dpi) became a 37.6 KB djvu.
- a 2.8 MB pdf colour image (600 dpi) produced by my scan printer became a 176 KB djvu image (300 dpi)
Out of the third test, these tries do not seem very enticing as far as size saving is concerned. So, for the time being, it seems it does not make much sense to use pdf to produce djvu save for some rare use cases.
I also like to convert EPUB to customized pdf (in 9×12 cm format). I do not know how to it directly with djvu. There is one online tool that makes it cleanly.(
https://convertio.co/). However there seems to be no way to tell it beforehand what the dimensions of the output (width, height, margins) should be like we can do with the Prince PDF plugin. Hopefully one day, a new Sigil plugin may appear to go directly from epub to djvu format.
I am not aware of any other easy way to produce djvu and get some of its size saving advantage (over pdf). But, probably I am missing something?