Updated eos to the latest master (v0.15.0), and updated the 4dface app code accordingly.
We make a few unnecessary cv::Mat to eos::core::Image<T> conversions, but overall, it seems to run faster, thanks to all the updates in eos. (There are still many things left to "modernise", but this first update seems to hopefully run fine.)
Make sure to clone the repository with git clone --recursive, or, if you're updating, run git submodule update --init --recursive.
As always, for people doing any serious computer vision work or research, I recommend directly working with the eos library, which is in active development and frequently updated.
There's also an updated precompiled binary for Windows available. No guarantees that it'll work on many other systems though, so these are not supported. The file opencv_ffmpeg341_64.dll needs to be copied to the bin/ directory alongside the other dll's.
Windows binaries are compiled for Windows 10 64bit, Visual Studio 2017 15.6.4.
If you use the binaries, you also have to download the landmark detector model (85 MB) and put it in the share/ directory: Download face_landmarks_model_rcr_68.bin.