1. An image processing apparatus comprising: a first image processing device configured to perform image processing affecting a high frequency component used to generate a detail component of an image; a detail component generating device configured to generate the detail component, which is emphasized, using an output of the first image processing device; an emphasis device configured to emphasize detail of the image by combining the emphasized detail component generated by the detail component generating device with the image; an emphasis amount controlling device configured to control an emphasis amount of the detail component generated by the detail component generating device; and a processing controlling device configured to control whether to perform the image processing by the first image processing device, wherein the processing controlling device controls the first image processing device to perform the image processing depending on a value set for the emphasis amount.