An image processing apparatus includes an image processor and an encoder. The image processor enhances an edge of an input image, removes noise from the input image, synthesizes the edge-enhanced image and the noise-removed image, and removes a high frequency from the synthesized image. The encoder pre-encodes a downsized synthesized image, obtains a pre-bit rate of the pre-encoded image, sets a quantization parameter value based on a reference bit rate and the pre-bit rate, and compresses the high-frequency removed image based on the quantization parameter value.