\documentclass[a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[french]{babel}
\usepackage[final]{pdfpages}
\begin{document}
\includepdf[pages=-]{page1.png}
\includepdf[pages=-]{page2.png}
\includepdf[pages=-]{page3.png}
\includepdf[pages=-]{page4.png}
\end{document}
