1. A method of encoding a video signal comprising: processing a video signal in a front-end image pre-processor to obtain a processed video signal and to extract sharpness information from the video signal based on an auto-focus algorithm; providing the processed video signal and the sharpness information to a video encoder; classifying regions of images represented by the video signal into a first type of region and a second type of region based on the sharpness information; performing rate control for a video encoding process by assigning more bits to the first type of region in the images represented by the video signal and fewer bits to the second type of region in the images represented by the video signal; and encoding the video signal in the video encoder according to the video encoding process based on the rate control to provide an encoded video signal.