An imaging apparatus for performing efficient signal processing depending on the operational mode. In the finder mode, a CCD interface 21a decimates horizontal components of image data supplied from an image generating unit 10 to one-third and moreover processes the decimated image data with data conversion and resolution conversion to produce Y, Cb and Cr image data which are routed to and written in an image memory 32 over a memory controller 22. In the recording mode, the CCD interface 21a causes the image data from the image generating unit 10 to be written in the image memory 32 via memory controller 22 after decimation and gamma correction etc. The camera DSP 21c reads out the image data via memory controller 22 from the image memory 32 to effect data conversion for writing the resulting data via memory controller 22 in the image memory 32.