An imaging apparatus comprising: an imaging section that includes an optical filter having a plurality of color filters for a plurality of colors and arranged in horizontal and vertical directions and an imaging device having a plurality of pixels arranged as corresponding to the color filters, the imaging section converting an input optical signal into pixel signals that correspond to the colors and sequentially outputting the pixel signals; a pixel-signal generating section, responsive to the sequentially output pixel signals including a first pixel signal generated from a target pixel among the pixels of the imaging device, to output second pixel signals together with the first pixel signal, the second pixel signals being generated from same-color neighboring pixels having the same color as the target pixel, the same-color neighboring pixels belonging to the pixels of the imaging device and being located as close to the target pixel on both sides of the target pixel in each of the horizontal and vertical directions; characterised by: a first extractor to extract a highest-level pixel signal having the highest luminance level and a first second-level pixel signal having a first second luminance level next to the highest luminance level among the second pixel signals; an average-level calculation section to calculate an average luminance level of the second pixel signals; a first determining section to determine whether a particular pixel belonging to the same-color neighboring pixels and causing generation of the highest-level pixel signal is defective or not by using the highest luminance level and the average luminance level; a selecting section to select the highest-level pixel signal when it is determined that the particular pixel is not defective whereas the first second-level pixel signal when determined that the particular pixel is defective; a second determining section to determine whether the target pixel is defective or not by using a level of the first pixel signal and a level of the selected pixel signal; and a replacing section to output the first pixel signal when it is determined that the target pixel is not defective whereas the selected pixel signal in place of the first pixel signal when determined that the target pixel is defective. an imaging section that includes an optical filter having a plurality of color filters for a plurality of colors and arranged in horizontal and vertical directions and an imaging device having a plurality of pixels arranged as corresponding to the color filters, the imaging section converting an input optical signal into pixel signals that correspond to the colors and sequentially outputting the pixel signals; a pixel-signal generating section, responsive to the sequentially output pixel signals including a first pixel signal generated from a target pixel among the pixels of the imaging device, to output second pixel signals together with the first pixel signal, the second pixel signals being generated from same-color neighboring pixels having the same color as the target pixel, the same-color neighboring pixels belonging to the pixels of the imaging device and being located as close to the target pixel on both sides of the target pixel in each of the horizontal and vertical directions; a first extractor to extract a highest-level pixel signal having the highest luminance level and a first second-level pixel signal having a first second luminance level next to the highest luminance level among the second pixel signals; an average-level calculation section to calculate an average luminance level of the second pixel signals; a first determining section to determine whether a particular pixel belonging to the same-color neighboring pixels and causing generation of the highest-level pixel signal is defective or not by using the highest luminance level and the average luminance level; a selecting section to select the highest-level pixel signal when it is determined that the particular pixel is not defective whereas the first second-level pixel signal when determined that the particular pixel is defective; a second determining section to determine whether the target pixel is defective or not by using a level of the first pixel signal and a level of the selected pixel signal; and a replacing section to output the first pixel signal when it is determined that the target pixel is not defective whereas the selected pixel signal in place of the first pixel signal when determined that the target pixel is defective.