1. An image recording and reproducing apparatus that records and reproduces image data shot at a frame rate higher than a normal reproduction rate employed during reproduction of a moving image, the apparatus comprising: a moving image storage period setting unit configured to set a moving image storage period in order to determine the number of frame images to be combined when the image data is reproduced as a moving image; a still image storage period setting unit configured to set a still image storage period in order to set the number of frame images to be combined when the image data is reproduced as a still image; a parameter attaching unit configured to attach a parameter indicating the moving image storage period and a parameter indicating the still image storage period to each frame image of the image data; an image recording unit configured to record the image data attached with the parameters by the parameter attaching unit; and a still image recording instructing unit configured to give an instruction to start recording a still image, wherein the parameter attaching unit attaches information indicating the start of recording of the still image to a frame image of the image data in response to the still image recording start instruction received during a recording operation performed by the image recording unit.