APPARATUS FOR ENCODING AND DECODING IMAGE AND METHOD THEREOF

摘要

An apparatus for encoding and decoding an image and a method thereof are provided to encode and decode the image by using a quantization parameter determined by using allowable noise without any subjective loss, thereby significantly improving encoding efficiency and subjective image quality of a restored image. An apparatus for encoding an image comprises the following parts: a transform unit(110) for removing spatial redundancy by transforming an inputted original image; an allowable noise obtaining unit(130) for obtaining allowable noise from the original image; a quantization parameter determining unit(150) for determining a quantization parameter by using the allowable noise; a quantization unit(170) for generating a quantized coefficient by quantizing a transform coefficient, provided from the transform unit, by using the quantization parameter; and an entropy encoding unit(190) for performing entropy encoding of the quantized coefficient in order to remove statistical redundancy.