The following command should work to build Multiblend on Linux:

  g++ -msse4.1 -pthread -ffast-math -Ofast -o multiblend multiblend.cpp -lm -lpng -ltiff -ljpeg

Harry van der Wolf suggests the following for Mac:

  [install home brew]
  brew install jpeg-turbo libjpeg libpng libtiff
  gcc -I/usr/local/opt/jpeg-turbo/include -L/usr/local/opt/jpeg-turbo/lib -std=c++14 -msse4.1 -pthread -ffast-math -Ofast -o multiblend multiblend.cpp -lm -lpng -ltiff -ljpeg -lstdc++
