Image encoding method using a skip mode, and a device using the method
Disclosed are an image encoding method using a skip mode and a device using the method. The image encoding method may comprise the steps of: judging whether there is residual block data of a prediction target block on the basis of predetermined data indicating whether residual block data has been encoded; and, if there is residual block data, restoring the prediction target block on the basis of the residual block data and an intra-screen predictive value of the prediction target block. Consequently, encoding and decoding efficiency can be increased by carrying out the encoding and decoding of screen residual data only for prediction target blocks where there is a need for a residual data block in accordance with screen similarity.
1 . A video decoding method, comprising:
determining a prediction mode of a current block;
generating a prediction block for the current block by performing intra prediction for the current block using the prediction mode and a plurality of reference pixels; and
generating a reconstructed block for the current block using the prediction block,
wherein the plurality of reference pixels comprise an upper-left reference pixel which is diagonally adjacent to an upper-left corner of the current block and an upper reference pixel which is vertically adjacent to an upper side of the current block, and
wherein a prediction value of the prediction block is determined based on a difference value between pixel values of the upper reference pixel and the upper-left reference pixel.
2 . The video decoding method of claim 1 , wherein the prediction value of the prediction block is generated using weights for two values determined based on at least three of the plurality of reference pixels and the prediction mode.
3 . The video decoding method of claim 1 ,
wherein an x-coordinate of the left reference pixel is smaller than a x-coordinate of a pixel located at an upper left of the current block by 1, and
wherein an y-coordinate of the upper reference pixel is smaller than a y-coordinate of a pixel located at an upper left of the current block by 1.
4 . The video decoding method of claim 1 , wherein a prediction value of the prediction block is determined based on prediction values predicted by a plurality of prediction modes, and
the intra prediction is performed based on whether intra prediction is used for each adjacent block of a plurality of adjacent blocks of the current block.
5 . The video decoding method of claim 4 , wherein the prediction value of the prediction block corresponds to an average of the prediction values predicted by the plurality of prediction modes.
6 . The video decoding method of claim 4 , wherein the prediction value of the prediction block corresponds to a weighted sum of the prediction values predicted by the plurality of prediction modes.
7 . The video decoding method of claim 1 , wherein the prediction mode of the intra prediction is a horizontal mode.
8 . A video encoding method, comprising:
determining a prediction mode of a current block;
generating a prediction block for the current block by performing intra prediction for the current block using the prediction mode and a plurality of reference pixels; and
generating a reconstructed block for the current block using the prediction block,
wherein the plurality of reference pixels comprise an upper-left reference pixel which is diagonally adjacent to an upper-left corner of the current block and an upper reference pixel which is vertically adjacent to an upper side of the current block, and
wherein a prediction value of the prediction block is determined based on a difference value between pixel values of the upper reference pixel and the upper-left reference pixel.
9 . The video encoding method of claim 8 , wherein the prediction value of the prediction block is generated using weights for two values determined based on at least three of the plurality of reference pixels and the prediction mode.
10 . The video encoding method of claim 8 ,
wherein an x-coordinate of the left reference pixel is smaller than a x-coordinate of a pixel located at an upper left of the current block by 1, and
wherein an y-coordinate of the upper reference pixel is smaller than a y-coordinate of a pixel located at an upper left of the current block by 1.
11 . The video encoding method of claim 8 , wherein a prediction value of the prediction block is determined based on prediction values predicted by a plurality of prediction modes, and
wherein the prediction is performed based on whether intra prediction is used for each adjacent block of a plurality of adjacent blocks of the current block.
12 . The video encoding method of claim 8 , wherein the prediction mode of the intra prediction is a horizontal mode.
13 . A non-transitory computer-readable recording medium storing program instructions for transmitting a bitstream, the program instructions comprising:
an instruction to perform generating the bitstream; and
an instruction to transmit the bitstream,
wherein the generating the bitstream comprises:
generating the bitstream comprising prediction information;
wherein the prediction information is generated by a video encoding method,
wherein the video encoding method comprises:
determining a prediction mode of a current block;
generating a prediction block for the current block by performing intra prediction for the current block using the prediction mode and a plurality of reference pixels; and
generating a reconstructed block for the current block using the prediction block,
wherein the prediction information indicates the prediction mode of the current block,
wherein the plurality of reference pixels comprise an upper-left reference pixel which is diagonally adjacent to an upper-left corner of the current block and an upper reference pixel which is vertically adjacent to an upper side of the current block, and
wherein a prediction value of the prediction block is determined based on a difference value between pixel values of the upper reference pixel and the upper-left reference pixel.
14 . The non-transitory computer-readable recording medium of claim 13 , wherein the prediction value of the prediction block is generated using weights for two values determined based on at least three of the plurality of reference pixels and the prediction mode.
15 . The non-transitory computer-readable recording medium of claim 13 ,
wherein an x-coordinate of the left reference pixel is smaller than a x-coordinate of a pixel located at an upper left of the current block by 1, and
wherein an y-coordinate of the upper reference pixel is smaller than a y-coordinate of a pixel located at an upper left of the current block by 1.
16 . The non-transitory computer-readable recording medium of claim 13 , wherein a prediction value of the prediction block is determined based on prediction values predicted by a plurality of prediction modes, and
the prediction is performed based on whether intra prediction is used for each adjacent block of a plurality of adjacent blocks of the current block.
17 . The non-transitory computer-readable recording medium of claim 13 , wherein the prediction mode of the intra prediction is a horizontal mode.
18 . A non-transitory computer-readable recording medium configured to store and transmit a bitstream generated by a computer program, wherein, the computer program, when executed by a processor, causes a video encoding apparatus to perform following steps to generate the bitstream:
determining a prediction mode of a current block;
generating a prediction block for the current block by performing intra prediction for the current block using the prediction mode and a plurality of reference pixels;
generating a reconstructed block for the current block using the prediction block; and
storing the bitstream comprising prediction information in the non-transitory computer-readable recording medium,
wherein the prediction information indicates the prediction mode of the current block,
wherein the plurality of reference pixels comprise an upper-left reference pixel which is diagonally adjacent to an upper-left corner of the current block and an upper reference pixel which is vertically adjacent to an upper side of the current block, and
wherein a prediction value of the prediction block is determined based on a difference value between pixel values of the upper reference pixel and the upper-left reference pixel.
19 . The non-transitory computer-readable recording medium of claim 18 , wherein the prediction value of the prediction block is generated using weights for two values determined based on at least three of the plurality of reference pixels and the prediction mode.
20 . The non-transitory computer-readable recording medium of claim 18 ,
wherein an x-coordinate of the left reference pixel is smaller than a x-coordinate of a pixel located at an upper left of the current block by 1, and
wherein an y-coordinate of the upper reference pixel is smaller than a y-coordinate of a pixel located at an upper left of the current block by 1.
21 . The non-transitory computer-readable recording medium of claim 18 , wherein a prediction value of the prediction block is determined based on prediction values predicted by a plurality of prediction modes, and
wherein the prediction is performed based on whether intra prediction is used for each adjacent block of a plurality of adjacent blocks of the current block.
22 . The non-transitory computer-readable recording medium of claim 18 , wherein the prediction mode of the intra prediction is a horizontal mode.