An image processing apparatus being connectable to a scanning unit that performs scanning for image reading on an image carrier carrying image information by moving an optical head relative to the image carrier and that reads a one-dimensional line image in a main scanning direction line by line by performing reciprocating scanning, in which forward scanning and backward scanning are alternately repeated for each line in the main scanning direction, and reads a two-dimensional image by performing scanning in a sub-scanning direction perpendicular to the main scanning direction in combination with the reciprocating scanning, that acquires the two-dimensional image from the scanning unit, and performs image processing on the two-dimensional image, the apparatus comprising: an abnormal pixel removing unit that removes a dot-shaped abnormal pixel by changing its pixel value present in the two-dimensional image based on neighboring pixels present around the abnormal pixel, and that selects the neighboring pixels from only at least one odd line including an odd line, in which a target pixel to be corrected in order to remove the abnormal pixel is present, in a case where a line in which the target pixel is present is an odd-numbered line in the sub-scanning direction, and selects the neighboring pixels from only at least one even line including an even line, in which the target pixel is present, in a case where a line in which the target pixel is present is an even-numbered line in the sub-scanning direction, and removes the abnormal pixel based on the selected neighboring pixels; and a tailing removing unit that removes stripe-shaped tailing, which occurs every other line due to the reciprocating scanning in the two-dimensional image and extends in the main scanning direction, from the two-dimensional image, wherein the tailing removing unit performs tailing determination processing in which a pixel value of the target pixel is compared with pixel values of upper and lower pixels adjacent to the target pixel in the sub-scanning direction and the target pixel is determined to be a tailing pixel forming the tailing in a case where the pixel value of the target pixel is higher than the pixel values of the upper and lower pixels and a difference or a ratio between the pixel value of the target pixel and the pixel values of the upper and lower pixels is equal to or greater than a predetermined value. an abnormal pixel removing unit that removes a dot-shaped abnormal pixel by changing its pixel value present in the two-dimensional image based on neighboring pixels present around the abnormal pixel, and that selects the neighboring pixels from only at least one odd line including an odd line, in which a target pixel to be corrected in order to remove the abnormal pixel is present, in a case where a line in which the target pixel is present is an odd-numbered line in the sub-scanning direction, and selects the neighboring pixels from only at least one even line including an even line, in which the target pixel is present, in a case where a line in which the target pixel is present is an even-numbered line in the sub-scanning direction, and removes the abnormal pixel based on the selected neighboring pixels; and a tailing removing unit that removes stripe-shaped tailing, which occurs every other line due to the reciprocating scanning in the two-dimensional image and extends in the main scanning direction, from the two-dimensional image, wherein the tailing removing unit performs tailing determination processing in which a pixel value of the target pixel is compared with pixel values of upper and lower pixels adjacent to the target pixel in the sub-scanning direction and the target pixel is determined to be a tailing pixel forming the tailing in a case where the pixel value of the target pixel is higher than the pixel values of the upper and lower pixels and a difference or a ratio between the pixel value of the target pixel and the pixel values of the upper and lower pixels is equal to or greater than a predetermined value.