X-rayimaging is usually performed by “penetration” imaging. We have reported material identification imaging studies in penetration X-ray imaging and X-ray CT imaging using an energy-discriminating CdTe semiconductor X-ray image sensor of the photon-charge counting type that we have developed. In this study, we attempted to identify the enveloped material by taking advantage of the fact that the energy distribution of these two types of scattering differs from material to material and that the energy distribution of Compton scattering depends on the scattering angle.