Étiquette : png

  • [Debian] Generate TeX formulas as SVG or PNG images Wikipédia-like

    Preparation

    We will use this file named texfile.tex as the .tex to convert:

    Result file

    PNG demonstration
    PNG demonstration

    Generating PNG images

    Packages you need:

    • texlive (or any other TeX program, I guess)
    • dvipng

    Step by step

    1. In the Terminal, go to the directory containing the .tex file.
    2. Execute this:
      • Output:
    3. Convert to PNG at 150dpi (to get a larger image than default):
      • Output:
    4. Remove the border white spaces of the page and add some borders using imagemagick:
    5. Your file is ready as texfile_trimmed.png.

    Script

    I have made a little script to automatize the conversion, with auto-remove of intermediary files:

    Usage
    1. Save the above script as tex2png, anywhere you want, usually near your .tex files for convenience.
    2. Make it executable: $ chmod +x tex2png.
    3. Syntax: tex2png filename [-keeptempfiles].
      • Example: $ tex2png texfile.tex.
      • Alternatively, you can omit the .tex extension: $ tex2png texfile but I would not recommend it.
      • If you want to keep the intermediary files (dvi, log, etc.), add the -keeptempfiles argument at the end: $ tex2png texfile.tex -keeptempfiles.
    4. The final image is named texfile_trimmed.png

    Generating SVG images

    Packages you need:

    • texlive

    Step by step

    1. In the Terminal, go to the directory containing the .tex file.
    2. Execute this:
      • Output:
    3. Convert to a SVG image with a 1.5 scale factor:
    4. Your file is ready as texfile.svg.

    Remarks

    There is no padding in the SVG method. I have not found yet a method to add a little padding around the figure.

    Also, the --no-fonts is necessary to prevent rendering issues about SVG fonts, especially with Firefox and the default SVG viewer of Debian. So the generated formula will not be selectable as a text, but at least, it will render correctly on every device with SVG support.

    Background

    I needed to include some nice looking formulas on my new game design wiki. I am using MediaWiki but the math add-on was not working on my server (web hosting service, not mine). So I decided to create myself the images offline and upload them as regular image files, so that I don’t need to think too much about trying to set the add-on without having all the privileges I could have on a personal server.