Bioniconv is a single pass bionic reading converter for epub files. It is written in Rust for single threaded performance.
Example usage:
$ cargo build --release
$ ./target/release/bioniconv path/to/file.epubIt produces new file in a current working directory with the same name as the input file but with bionic_ prefix.
The image below shows before and after conversion of a page from a book.
On my machine the King James Bible epub file, 1.7MiB of compressed text, was converted in less than a second.
$ time ./target/release/bioniconv ~/Downloads/pg10900.epub
real 0m0.937s
user 0m0.589s
sys 0m0.041s