Epublatex

A Go program to convert a subset of LaTeX into EPUB format.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Overview

Epublatex can convert a subset of LaTeX into EPUB format. For compatibility with older ebook readers, formulas are rendered into images (using pdflatex), and the rest of the LaTeX source is converted into HTML; both the HTML and the rendered images are then combined into an EPUB 3.0 file.

This program is not yet finished, and may not yet be usable for any real projects. Contributions in the form of patches would be very welcome.

Experimenting with the Code

The project has the following dependencies:

go (to run/compile the source code)

pdflatex (to convert formulas to pdf)

ghostscript (to convert pdf to png)

To experiment with the current code:

git checkout https://github.com/seehuhn/epublatex
cd epublatex
go run main.go examples/nonsense.tex

This will hopefully generate EPUB output in the file nonsense.epub. The code still has many rough edges and known problems:

Only a small subset of LaTeX is implemented.

I am still making large changes to the code without any attempt at backwards compatibility.

Note: The program keeps a cache of rendered images in some directory ($HOME/Library/Caches/de.seehuhn.ebook/maths/ on MacOS, and $HOME/.cache/de.seehuhn.ebook/maths/ on Linux).

Structure of the Code

The epublatex source code is split over a number of packages:

github.com/seehuhn/epublatex/epub - Backend for storing HTML data in an EPUB 3.0 container.

github.com/seehuhn/epublatex/latex/scanner - Buffered reading of the source files, handling of include files.

github.com/seehuhn/epublatex/latex/tokenizer - Splits the LaTeX source into tokens. This package has quite a bit of knowledge about LaTeX, in order to correctly identify macro arguments.

github.com/seehuhn/epublatex/latex/math - Uses pdflatex and ghostscript to convert mathematical formulas into PNG images.

github.com/seehuhn/epublatex/latex - Ties all the other components together, converts LaTeX to HTML, writes the result into an EPUB file.