An image processing system includes an acquiring unit configured to acquire image data; a first determination unit configured to create histograms of colors in the acquired image data, and determine deemed background colors with the use of the histograms; a second determination unit configured to determine a background color based on the deemed background colors; a counting unit configured to count a number of pixels corresponding to character colors in the image data, wherein colors other than the background color are the character colors; and a deciding unit configured to obtain a ratio of the number of pixels corresponding to the character colors to a total number of pixels in the image data, and perform blank page determination on the image data by determining that the image data is blank when the ratio is less than a predetermined value.