Dispersion of Core Shell particles (CS) in an epoxy network was analyzed by manual and automatic image processing methods yielding quantitative morphological indexes. These indexes were mainly based on the classical coefficient of variation, used for the statistics of the particles counted in a grid, or for the neighbor distances. The rubbery CS were either commercial or home made having different core nature, shell thickness and functionnalization (carboxy or epoxy). Two dispersion methods were used: a laboratory high speed mixer ("Ultraturrax"), or a co-rotating twin screw extruder with different screw profiles and temperature. The shell functionnalization was to be a key factor leading to high dispersion. Samples were taken along the extruder screws and analyzed. Multiple kneading blocs followed by reverse screw element were necessary for the obtention of a dispersion equivalent to the one obtained using the "Ultraturrax". The presence of particles (9.5 to 24% in volume) slightly decreased the quasi-static mechanical properties, that is Young's modulus and yield strength. On the contrary, toughness is enhanced, as expected, especially with functionnalized particles. In addition, the scatter on the fracture properties was directly related to the morphological heterogeneity index.