Source: {"pile_set_name": "USPTO Backgrounds"}

Field of the Invention
The present invention relates to a method and apparatus of video encoding/decoding, and more particularly, to a method that performs intra prediction by using interpolation filtering while encoding and decoding.
Discussion of the Related Art
In general, a residual signal is generated by using intra prediction and inter prediction while video coding. The reason for acquiring the residual signal is that when the residual signal is coded with the residual signal, the quantity of data is small and a data compression rate increases and as the prediction is better, a signal of the residual signal is small.
In an intra prediction method, data of a current block is predicted by using contiguous pixels of the current block. A difference between an actual value and a prediction value is referred to as a residual signal block. In the case of HEVC, in the intra prediction method, 9 prediction modes used in the existing H.264/AVC increases to 35 predictions modes as illustrated in FIG. 1 to be more subdivided, and as a result, the prediction is performed (however, a planar prediction mode and a DC prediction mode are not shown in FIG. 1).
In the case of the inter prediction method, the current block is compared with blocks in contiguous pictures to find a most similar block. In this case, positional information (Vx, Vy) of the found block is referred to as a motion vector. A difference of pixels in the block between the current block and the prediction block predicted by the motion vector is referred to as the residual signal block (motion-compensated residual block).
As described above, a video encoding and decoding method is required, in which the intra prediction and the inter prediction are subdivided to decrease the quantity of data of the residual signal and a calculation quantity is small without degradation of codec performance by using efficient transform.