An imaging apparatus comprising: an image sensor having a light receiving surface including a plurality of pixels and a color separation filter of a plurality of colors which is placed on a front surface side of the plurality of pixels, wherein said image sensor is configured to receive a photographic subject image which enters via an optical system on the light receiving surface via the color separation filter, outputs a pixel output of each pixel comprising data having a first bit number, and images the photographic subject image; a pixel output judging section configured to judge whether the pixel output is saturated or unsaturated respectively based on whether the pixel output is equal to or less than a saturation level; a pixel output compensation processing section configured to perform a compensation process on a first pixel corresponding to a first color of the color separation filter, said first pixel having a saturated pixel output, wherein the pixel outputs are converted from data having the first bit number to data having a second bit number, the second bit number being larger than the first bit number, and the pixel output of the first pixel is compensated to become greater than or equal to the saturation level based on the pixel output of a second pixel corresponding to a second color of the color separation filter, said second pixel having an unsaturated pixel value and being in the vicinity of the first pixel, so as to expand the dynamic range of the image the compensated first pixel comprising data having the second bit number; and characterised by: a bit compression converting section configured to convert pixel outputs comprising data having the second bit number to data having the first bit number, based on a data compression rate which is smaller for a pixel output less than the saturation level and larger for a pixel output greater than or equal to the saturation level. an image sensor having a light receiving surface including a plurality of pixels and a color separation filter of a plurality of colors which is placed on a front surface side of the plurality of pixels, wherein said image sensor is configured to receive a photographic subject image which enters via an optical system on the light receiving surface via the color separation filter, outputs a pixel output of each pixel comprising data having a first bit number, and images the photographic subject image; a pixel output judging section configured to judge whether the pixel output is saturated or unsaturated respectively based on whether the pixel output is equal to or less than a saturation level; a pixel output compensation processing section configured to perform a compensation process on a first pixel corresponding to a first color of the color separation filter, said first pixel having a saturated pixel output, wherein the pixel outputs are converted from data having the first bit number to data having a second bit number, the second bit number being larger than the first bit number, and the pixel output of the first pixel is compensated to become greater than or equal to the saturation level based on the pixel output of a second pixel corresponding to a second color of the color separation filter, said second pixel having an unsaturated pixel value and being in the vicinity of the first pixel, so as to expand the dynamic range of the image the compensated first pixel comprising data having the second bit number; and characterised by: a bit compression converting section configured to convert pixel outputs comprising data having the second bit number to data having the first bit number, based on a data compression rate which is smaller for a pixel output less than the saturation level and larger for a pixel output greater than or equal to the saturation level.