An image processing apparatus, comprising: an imaging unit configured to capture an object image and generate a RAW image; a first development unit configured to perform first development processing on the RAW image; a storage unit configured to store in a storage medium an image file of an image developed by the first development unit, and a RAW file of the RAW image in accordance with an instruction for image capturing; a second development unit configured to perform second development processing on the RAW image to obtain an image having higher image quality than that obtained by the first development unit; and a reproduction unit (151, 122) configured to output an image developed by the first or the second development unit as a reproduction image, wherein when load of the image processing apparatus is small, the second development unit is configured to perform the second development processing on the RAW image stored in the storage medium and the storage unit is configured to store in the storage medium an image file of an image developed by the second development unit, wherein when an instruction for reproduction of a certain image is given, if the second development unit has not completed developing of the RAW image, the reproduction unit is configured to output the image of the image file recorded in the storage medium and developed by the first development unit and, if the second development unit has completed developing of the RAW image and the image file of the image developed by the second development unit is stored in the storage medium, the reproduction unit is configured to output the image developed by the second development unit, characterized in that if an instruction for enlarging a partial area is given when the image developed by the first development unit is output as a reproduction image, the second development unit is configured to perform the second development processing on the RAW image stored in the storage medium if it is determined that said image has still not been developed by said high-quality second development unit, and the reproduction unit is configured to output said partial enlarged area of the image developed by the second development unit. an imaging unit configured to capture an object image and generate a RAW image; a first development unit configured to perform first development processing on the RAW image; a storage unit configured to store in a storage medium an image file of an image developed by the first development unit, and a RAW file of the RAW image in accordance with an instruction for image capturing; a second development unit configured to perform second development processing on the RAW image to obtain an image having higher image quality than that obtained by the first development unit; and a reproduction unit (151, 122) configured to output an image developed by the first or the second development unit as a reproduction image, wherein when load of the image processing apparatus is small, the second development unit is configured to perform the second development processing on the RAW image stored in the storage medium and the storage unit is configured to store in the storage medium an image file of an image developed by the second development unit, wherein when an instruction for reproduction of a certain image is given, if the second development unit has not completed developing of the RAW image, the reproduction unit is configured to output the image of the image file recorded in the storage medium and developed by the first development unit and, if the second development unit has completed developing of the RAW image and the image file of the image developed by the second development unit is stored in the storage medium, the reproduction unit is configured to output the image developed by the second development unit, characterized in that if an instruction for enlarging a partial area is given when the image developed by the first development unit is output as a reproduction image, the second development unit is configured to perform the second development processing on the RAW image stored in the storage medium if it is determined that said image has still not been developed by said high-quality second development unit, and the reproduction unit is configured to output said partial enlarged area of the image developed by the second development unit.