Provided is a technology capable of simply and efficiently obtaining a contrast of a speckle pattern as a prerequisite for measuring a fluid velocity.The present technology provides an information processing apparatus including: a luminance integrator that integrates a luminance of a plurality of speckle images obtained by an imaging element by a plurality of times of imaging of scattered light obtained from an imaging target to which coherent light is emitted； and a contrast calculation unit that calculates a contrast of a speckle pattern on the basis of a speckle integrated image integrated by the luminance integrator.
