Imaging apparatus including noise suppression circuit

An imaging apparatus comprising:

• an imaging section in which a plurality of pixels formed of photoelectric conversion elements are two-dimensionally arranged and a color filter arrangement has a cross of five pixels of a same color;
• and a noise suppression circuit which performs predetermined signal processing with respect to image signals respectively output from the imaging section,
• wherein the noise suppression circuit includes:
• sorting processing of sorting one signal of a central pixel as a target and four signals of peripheral pixels having the same color which are close to the central pixel in crossing directions or X-shaped directions in the image signals in order of magnitude;
• difference value calculation processing of calculating a first difference value from a maximum value and a minimum value of the one signal of the central pixel and the four signals of the peripheral pixels sorted in order of magnitude;
• average value calculation processing of calculating a first average value from the one signal of the central pixel and the four signals of the peripheral pixels;
• comparison processing of comparing the first difference value with an assumed noise level;
• and
• substitution processing of substituting the one signal of the central pixel by the first average value when the first difference value is smaller than the noise level;
• substitution processing of substituting the one signal of the central pixel by an average value of two or more pixel values excluding at least the maximum value or the minimum value when the first difference value is larger than the noise level,
• wherein, when the central pixel is Gr or Gb,
• the noise suppression circuit further calculates a second average value from one signal of a central Gr or Gb pixel as a target, four signals of peripheral Gr or Gb pixels which are respectively close to the central Gr or Gb pixel in crossing directions, and four signals of peripheral Gb or Gr pixels which are respectively close to the central Gr or Gb pixel in X-shaped directions, calculates a second difference value from a maximum value and a minimum value from the one signal of the central Gr or Gb pixel and the eight signals of the peripheral Gr or Gb signals, and substitutes the one signal of the central Gr or Gb pixel by the second average value if the second difference value is smaller than the noise level.