A multi-beam charged-particle microscope apparatus 100 includes an irradiation system 104 that irradiates a plurality of regions on a surface of a sample 9 with a plurality of beams, a detection system 125 (correction detector 132 and imaging detector 131) that detects emitted electrons from the surface of the sample 9, and a controller 102 that generates a first brightness of a first pixel in a first region based on a first signal of a first detector of a multi-detector 123 and generates a second brightness of a second pixel in a second region based on a second signal of a second detector. A processor of a processor system 103 that can communicate with the charged-particle microscope apparatus 100 specifies a first crosstalk amount from a second emitted electron to the first signal based on the first brightness obtained from the charged-particle microscope apparatus 100 and an output of the correction detector 132 and corrects the first brightness based on the first crosstalk amount.