natanael.arndt.xyz

At some event we had a screen to show some slides, as well as a pre-produced video, to summarize our project outcomes. Since my presentation tool-chain mostly involves LaTeX beamer slides, I came up with the following script to convert the PDF pages into video frames and concatenate another video file.

#!/bin/sh

convert -density 609 -resize 1920x1080 main.pdf video/picture.png
cd video
ffmpeg -r 1/6 -i picture-%01d.png -c:v libx264 -r 30 video.mp4
ffmpeg -i video.mp4 -i second_video.mp4 -f lavfi -t 1 -i anullsrc -filter_complex "[0:v][2:a] [1:v] [1:a] concat=n=2:v=1:a=1 [v] [a]" -map "[v]" -map "[a]" out.mkv

The inputs are:

• main.pdf with your slides
• video/second_video.mp4 with the video you want to attach

The output will be at video/out.mkv.

The slides should be in 16:9 format, so that it nicely scales to 1920x1080 (Full-HD). All other options should be documented at https://ffmpeg.org/.