1. An object information acquiring apparatus comprising: an acoustic detector configured to receive an acoustic wave, the acoustic wave being a photoacoustic wave generated from the object irradiated with light from a light source; an object information distribution processor configured to generate an object information distribution representing a property of inside of the object by using a signal derived from the acoustic wave outputted from the acoustic detector; a reliability distribution generator configured to generate a reliability distribution by using the object information distribution; a similarity distribution generator configured to generate a similarity distribution between template distribution data indicating a relation between a real image and an artifact in the image data, and the object information distribution; and a combination processor configured to generate a combined distribution by performing combination processing of the reliability distribution and the similarity distribution.