I was unable to extract any of ImgV64 download packages with either Uniextractor or Lessmsi, so I had to do an install/uninstall cycle which yielded a single executable for each. ImgV64 features some editing capacity but sadly isn't natively portable, as it saves its very few settings to 'HKCU\Software\ImgV64\ImgV64'.
ImgV64 is a Windows Vista/Win7/Win8/Win10 graphics viewer for GIF, JPG, PNG and other formats. It is designed for those who want a solid, easy viewer but who still want powerful features, without the complexity of a complete paint or thumbnailing program.
ImgV64 latest release (currently v1.48) can be downloaded from http://imgv64.co.nf/.