I would recommend "Graphics and Graphic Information Processing" by Bertin over La Semiologie simply because the latter reads more like a reference book where Be

I would recommend "Graphics and Graphic Information Processing" by Bertin over La Semiologie simply because the latter reads more like a reference book where Bertin is extremely thorough. But GGIP gets straight to the point and can frame your thinking while going through Semiologie such that you won't lose your way. Unfortunately GGIP is expensive so I would try to find it at your local library. (French copies are online).