1. A video decoding method using an intra prediction, the method comprising: predicting a current block from a plurality of neighboring blocks of the current block; decoding a bitstream to thereby extract residual signals; inversely quantizing the residual signals; inversely transforming the inversely quantized residual signals; and adding the inversely transformed residual signals to the predicted pixels in the predicted block, wherein the prediction of the current block comprises: calculating a plurality of weighted pixel values of pixels selected in the neighboring blocks by applying weights to the pixels selected in the neighboring blocks, wherein the weights are decided variably based on a position of a current pixel to be predicted in the current block; and deriving a predicted pixel value of the current pixel using the weighted pixel values, wherein the pixels selected in the neighboring blocks comprise: a first pixel which is included in an upper neighboring block and located at the same column with the current pixel, and a second pixel which is included in a left neighboring block and located at the same row with the current pixel.