An electronic device includes one or more processors and memory storing instructions for execution by the one or more processors. The stored instructions include instructions for: receiving infrared image information for a three-dimensional area; receiving non-infrared image information for the same three-dimensional area; performing nonlinear intensity adjustment for the received infrared image information; performing nonlinear intensity adjustment for the received non-infrared image information; blending the intensity-adjusted infrared image information and the intensity-adjusted non-infrared image information to obtain a merged image information; and providing the merged image information for determining a depth map. Also disclosed are a corresponding method performed by the electronic device and a computer readable storage medium storing instructions for execution by one or more processors of an electronic device.