Method and device for simplifying encoding and decoding of ultra-high definition images
Provided are an encoding device using predictive coding in a screen and a method thereof, and a decoding device and a method thereof. The encoding device is capable of generating a prediction block of a current block according to one of methods for generating a plurality of predetermined prediction blocks, and outputting at least one of encoding information and differential blocks as bitstream by entropy encoding according to whether differential blocks are encoded or not.
1. A method to decode a current block encoded in a bitstream using an intra prediction comprising: decoding direction information extracted from the bitstream in a case in which a residual block is not encoded in the bitstream;
generating a prediction block for the current block by performing the intra prediction using one or more reference blocks adjacent to the current block;
and generating a reconstructed block of the current block using a decoded residual block and the prediction block in a case that the residual block is encoded in the bitstream, and generating the reconstructed block using the prediction block in a case in which the residual block is not encoded in the bitstream, wherein the reconstructed block is generated based on the decoded direction information, the decoded direction information indicates a prediction block generating method used for encoding of the current block, and the prediction block generating method is selected from a plurality of intra prediction block generating methods that correspond to a plurality of different intra prediction directions, respectively.
2. The method of claim 1 , wherein the plurality of intra prediction block generating methods generate the prediction block by copying a value of a reference pixel of a reference block to one or more pixels of the prediction block in a prediction direction of each intra prediction block generating method of the plurality of intra prediction block generating methods in a case in which the residual block is not encoded in the bitstream.
3. A method to decode a current block encoded in a bitstream using an intra prediction comprising: decoding direction information extracted from the bitstream in a case that a residual block is not encoded in the bitstream;
generating a prediction block for the current block by performing the intra prediction using one or more reference blocks adjacent to the current block; and
generating a reconstructed block of the current block using a decoded residual block and the prediction block in a case that the residual block is encoded in the bitstream, and generating the reconstructed block using the prediction block in a case in which the residual block is not encoded in the bitstream, wherein the reconstructed block is generated based on the decoded direction information, the decoded direction information is used to determine one or more reference pixels of one or more reference blocks used to generate the prediction block, and the one or more reference blocks are adjacent to the current block.
4. The method of claim 3 , wherein the decoded direction information is related to a direction to select the one or more reference pixels of the current block.
5. A method to decode a current block encoded in a bitstream using an intra prediction, comprising:
performing entropy decoding on encoding information indicating whether a residual block for the current block is encoded in the bitstream;
performing entropy decoding on direction information used to determine one or more reference pixels in one or more reference blocks used to generate the prediction block for the current block in a case that the encoding information indicates that the residual block for the current block is not encoded in the bitstream;
generating the prediction block of the current block by performing the intra prediction using the one or more reference pixels in a case that the encoding information indicates that the residual block for the current block is not encoded in the bitstream; and
generating a reconstructed block of the current block using the prediction block in a case in which the encoding information indicates that the residual block for the current block is not encoded in the bitstream,
wherein the one or more reference blocks are adjacent to the current block, and
wherein the residual block is used for generating the reconstructed block in a case in which the encoding information indicates that the residual block for the current block is encoded in the bitstream.
6. The method of claim 5 , wherein the reconstructed block is equal to the prediction block in a case in which the residual block is not encoded in the bitstream.
7. The method of claim 5 , wherein the direction information indicates a prediction block generating method used for encoding of the current block selected from a plurality of intra prediction block generating methods in a case in which the encoding information indicates that the residual block for the current block is not encoded in the bitstream, and
wherein the plurality of intra prediction block generating methods generate the prediction block by copying the one or more reference pixels in a direction of each intra prediction block generating method of the plurality of intra prediction block generating methods in a case in which the encoding information indicates that the residual block for the current block is not encoded in the bitstream.