1. An image capturing apparatus comprising: an image capturing unit including an imaging sensor and capturing a subject image to generate RAW data; a generating unit generating a moving image file including ( 1 ) moving image data made up of a plurality of sets of RAW data which is generated by the image capturing unit, and ( 2 ) incidental information data corresponding to each of the sets of RAW data and including at least property information which includes parameter information regarding image processing for the RAW data; an information adding unit ( 1 ) generating, as new incidental information, the parameter information that changes continuously, the parameter information being interpolated between the sets of RAW data, the sets of RAW data being continuous in time sequence, existing within a predetermined range that includes both a set of RAW data before. and a set of RAW data after, a boundary of change of the parameter information regarding the image processing included in the property information, the boundary of change being made of two of the RAW data, and ( 2 ) adding the generated new incidental information to the incidental information data, the moving image file including control information data controlling a whole moving image and the incidental information data for each of a plurality of groups into which the sets of RAW data are grouped, the control information data including a capturing date and time of the moving image file and a first and last frame; and an accepting unit accepting a user's designation regarding image processing for the RAW data being desired among the moving image data and a user's designation regarding a designation of the desired RAW data; wherein the information adding unit ( 1 ) generates the new incidental information based on the desired RAW data designated by the user's designation via the accepting unit among the moving image file, and ( 2 ) adds the new incidental information being generated to the incidental information data.