This study reports on the mixed-mode behavior of desiccation cracks in a clayey rock front gallery. As most digital image correlation (DIC) algorithms have access to the full-field measurements of the displacements and strains, the improvements in DIC now allow the automatic detection of the jumps in the displacements induced by the opening and sliding of desiccation cracks without imposed initial conditions. This new local data allows us to specifically study the kinematics of the crack lips at each deformed state. These results allow us to quantify the opening and sliding of cracks and the cracked area during the desaturation and saturation paths of the rock mass. Amongst other results, a linear trend between the deformation of the solid phase and the crack porosity is observed. The results also demonstrate that most desiccation cracks evolve in a mixed-mode, the values of the shear component are of the same order of magnitude as the opening values.