An image processing apparatus comprising: an imaging unit configured to use an imaging sensor to acquire a RAW image representing a pre-development image from imaging signals of a subject image; a reduction unit configured to reduce the RAW image to generate a reduced RAW image; a first developing unit configured to acquire the reduced RAW image from the reduction unit when shooting and to perform developing processing of the reduced RAW image; a compression unit configured to compress each of the RAW image and the reduced RAW image; a recording unit configured to record each data of the compressed RAW image and the compressed reduced RAW image in a recording medium; a second developing unit configured to read out the compressed RAW image recorded in the recording medium when in an idle state, to perform developing processing of the RAW image in the background, and to generate a developed image; an instructing unit configured to instruct reproduction of the RAW image recorded in the recording medium; and a reproducing unit configured to, at the time of reproducing of a certain RAW image being instructed, perform reproduction output of the developed image in a case where developing processing of said RAW image by the second developing unit has ended, and to reproduce the reduced RAW image read out from the recording medium by performing developing processing of said reduced RAW image by the second developing unit when reproducing and by further performing reproduction output of the developed reduced image in a case where developing processing of the RAW image by the second developing unit has not ended. an imaging unit configured to use an imaging sensor to acquire a RAW image representing a pre-development image from imaging signals of a subject image; a reduction unit configured to reduce the RAW image to generate a reduced RAW image; a first developing unit configured to acquire the reduced RAW image from the reduction unit when shooting and to perform developing processing of the reduced RAW image; a compression unit configured to compress each of the RAW image and the reduced RAW image; a recording unit configured to record each data of the compressed RAW image and the compressed reduced RAW image in a recording medium; a second developing unit configured to read out the compressed RAW image recorded in the recording medium when in an idle state, to perform developing processing of the RAW image in the background, and to generate a developed image; an instructing unit configured to instruct reproduction of the RAW image recorded in the recording medium; and a reproducing unit configured to, at the time of reproducing of a certain RAW image being instructed, perform reproduction output of the developed image in a case where developing processing of said RAW image by the second developing unit has ended, and to reproduce the reduced RAW image read out from the recording medium by performing developing processing of said reduced RAW image by the second developing unit when reproducing and by further performing reproduction output of the developed reduced image in a case where developing processing of the RAW image by the second developing unit has not ended.