zip compression in epub via pandoc better than plain zip?

Question

I have a plain text file (scan of a book written about 100 years ago in english).

When I save it in my text editor it has size 618kb

Whan I zip this file it has size 211kb

but when I covert it to epub via pandoc it becomes just 32k.

I thought the epub file is basically just zip, so how come the epub is so small?

Answer 1

ok, just solved it.

The epub produced by pandoc was incomplete, because some odd characters in the OCR had caused pandoc to ignore the remainder of the book.