Export slides as PDF with 16:9 ratio

[acka47]

I had problems to export my slides in 16:9 for the KIM workshop. This issue is for documenting how I have done it.

• Install decktape
  • As there are problems with HummusJS and an up-to-date node version (see Install error with Node 13 astefanutti/decktape#201), I downgraded to node 12.14 (using $ nvm install 12.14) and then installed decktape using $ npm install -g decktape
• Convert the file to pdf with decktape adding fragments=true parameter to local file URL to have one slide for each fragment (see Add an option to toggle rendering fragments "all in one" or "one for each" slide(s) astefanutti/decktape#24 (comment)) e.g. $ decktape -s 1920x1080 reveal file:///home/acka47/git/slides/kim-ws-2020/index.html?fragments=true kim-ws-2020.pdf

[dr0i]

Thx for the decktape hint! Thx for the detailed explanations. Just a note - for my lightning talk no problems occured.

[acka47]

This method does not work anymore, the slides come out wrong, with the footer included (view count etc.):

Until now I have tried these solutions for exporting slides from pad.gwdg.de:

• The HedgeDoc CLI unfortunately does not support PDF export for slides yet. I have tried to download the slides locally with $ hedgedoc export --slides and tried the decktape command with the local files. To no surprise this does not change anything.
• Then I have tried the solution in Export to pdf hackmdio/codimd#33 (comment) with Chromium which works a bit better, however there are some things broken with regard to images and graphics in text.
• When I tried the same approach in Firefox it looked better, after adjusting image size for some slides it turned out well, except for the first page being blank. I added a blank first page in the markdown, and printed the PDF again. That's not perfect as well, but it hat to suffice.

[acka47]

Next try: use pandoc with $ pandoc https://pad.gwdg.de/p/2023-05-25-skohub@bibliocon23?print-pdf -t latex -o slides.pdf.This gives back:

pdflatex not found. Please select a different --pdf-engine or install pdflatex

This is solved by installing texlive-latex-recommended: $ sudo apt install texlive-latex-recommended. But then I get the next error:

Error producing PDF.
! LaTeX Error: File `letltxmacro.sty' not found.

This is solved by installing more than 200MB of texlive-latex-extra. Next error:

Error producing PDF.
! Package inputenc Error: Unicode character ➡ (U+27A1)
(inputenc)                not set up for use with LaTeX.

This is solved by using the --pdf-engine=xelatex option for which you need to install texlive-xetex.

Finally, this works $ pandoc --pdf-engine=xelatex https://pad.gwdg.de/p/2023-05-25-skohub@bibliocon23?print-pdf -t latex -o slides.pdf but the output is far from what we want.

I assume that how I approached to solve this problem with pandoc was somehow misguided.

[dr0i]

I got this working with at least nvm version 20.2.0. Doing this:
nvm install v20.2.0; npm install -g decktape ( this command takes >2m without any output , noting something about a pdf library or so ( remembering that at bibliocon2023 I waited more than 8m without any notification and then canceled it) - so just wait).

[acka47]

I got this working with at least nvm version 20.2.0. Doing this:
nvm install v20.2.0; npm install -g decktape

Thanks, @dr0i . Yes, this works with slides from slides.lobid.org but unfortunately not with HedeDoc slides from pad.gwdg.de (althoug it also uses reveal.js)...

[acka47]

Thanks, @dr0i . Yes, this works with slides from slides.lobid.org but unfortunately not with HedeDoc slides from pad.gwdg.de (althoug it also uses reveal.js)...

I am happy with the approach described in #59 (comment) . The only annoying thing is that I have to add a slide before the first one and remove it later in the PDF as otherwise the title slide is made blank. For removing the first slide from the PDF I used pdftk on the command line, e.g.: $ pdftk input.pdf cat 2-82 output output.pdf, where "82" has to be set to the number of te last slide.

[acka47]

Once again I ran into problems with creating a PDF from a HedgeDoc-based presentation. It's this one: https://pad.lobid.org/p/skohub@nfdi4ing-conference

This time the headings came out wrong and the logo wasn't taken over.

I've then tried another variant: as decktape created the slides with the footer (see #59 (comment)), I removed the footer in the CSS by adding:

    .footer {
        display: none;
    }

However, althuugh the text in the footer is not shown, the space is still occupied in the bottom of each slide and there are problems with emojis, e.g.:

[sroertgen]

After struggling with the pandoc approach for some time I gave decktape a try. And it just worked beautifully:

decktape https://pad.lobid.org/p/skohub@nfdi4ing-conference slides.pdf

being on manjaro I just installed decktape from the AUR