There is provided a method for performing digital processing on an image signal output from CCD image sensors with a CMYG color filter array, the method including converting a digital CMYG signal of 10 bits each into a first YCbCr signal of 10 bits each, by using color interpolation, converting the first YCbCr signal of 10 bits each into an RGB signal of 8 bits each by using interpolation, performing color correction on the RGB signal of 8 bits each and converting a color-corrected RGB signal of 8 bits each into a second YCbCr signal of 8 bits each in a format which complies with the ITU-601 format, encoding the second YCbCr signal of 8 bits each and converting an encoded second YCbr signal of 8 bits each into an analog video signal, and adjusting automatic exposure and automatic white balance, using the RGB signal of 8 bits each and the second YCbCr signal of 8 bits each.