1. An image processing method of an image processing system, the image processing system comprising a memory for storing programs and a picture image, and a processor for executing the programs stored in the memory, the picture image comprising a plurality of pixels, the method comprising: finding at least one image area with a predetermined characteristic from the picture image according to a predetermined image area detecting method; defining a boundary area around the image area according to a predetermined boundary area defining method; and adjusting pixels inside the image area according to a first color adjusting method, and adjusting pixels inside the boundary area according to a second color adjusting method without adjusting pixels outside the boundary area so that the second color adjusting method is only applied to the pixels lying inside the boundary area, wherein the second color adjusting method is different but similar to the first color adjusting method.