One particular object of the present invention is to facilitate high quality reproduction for an image combining an image based on rendered PDL commands and a scanned image without considering whether the processed pixel is a portion of the scanned image or a portion of the image base on rendered PDL commands. So the present invention relates to an image processing apparatus which include an inputting unit for inputting image data described by a command corresponding to each part of an image, an interpreting unit for interpreting the command to form a bitmap image and to output attribute information; a scanning unit for scanning an image to output color image data; a generating unit for generating flag data indicating attributions of the image based on the color image data and indicating the pixel preferring the same image process as the pixel based on the attribute information; a first combining unit for combining the color image data and the bitmap image; and a second combining unit for combining the flag data and the attribute information of the command.