Image encoding/decoding method using prediction block and apparatus for same
According to the present invention, an image encoding/decoding method comprises the steps of: performing an intra prediction on a current block so as to generate a prediction block; performing filtering on a filtering target pixel in the prediction block on the basis of the intra prediction mode of the current block so as to generate a final prediction block; and generating a reconstructed block on the basis of a reconstructed differential block corresponding to the current block and on the final prediction block. According to the present invention, image encoding/decoding efficiency can be improved.
1. A method for video decoding, the method comprising:
generating a prediction block by performing intra prediction on a current block, and
generating a reconstructed block based on the prediction block and a reconstructed residual block corresponding to the current block,
wherein:
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block,
the reference pixel is located in a vertical reference pixel line which adjacent to the left side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.
2. The method of claim 1 , wherein an intra prediction mode of the intra prediction is a Planar mode, and
the prediction block is generated based on a filter using the reference pixel and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.
3. The method of claim 2 , wherein whether or not to use the filter is determined based on a size of the current block.
4. The method of claim 2 , wherein the prediction pixel and the reference pixel are located on one horizontal line.
5. A method for video encoding, the method comprising:
generating a prediction block by performing intra prediction on a current block, and
generating a reconstructed block based on the prediction block and a reconstructed residual block corresponding to the current block,
wherein:
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block, and
the reference pixel is located in a vertical reference pixel line which adjacent to the left side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.
6. The method of claim 5 , wherein an intra prediction mode of the intra prediction is a Planar mode, and
the prediction block is generated based on a filter using the reference pixel and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.
7. The method of claim 6 , wherein whether or not to use the filter is determined based on a size of the current block.
8. The method of claim 6 , wherein the prediction pixel and the reference pixel are located on one horizontal line.
9. A non-transitory computer-readable medium storing a bitstream, the bitstream comprising:
prediction mode information indicating an intra prediction mode for a current block, wherein
a prediction block is generated by performing intra prediction on the current block using the prediction mode information,
a reconstructed block is generated based on the prediction block and a reconstructed residual block corresponding to the current block,
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block, and
the reference pixel is located in a vertical reference pixel line which adjacent to the let side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.
10. The non-transitory computer-readable medium of claim 9 , wherein the intra prediction mode is a Planar mode, and
the prediction block is generated based on a filter using the reference pixels and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.
11. The non-transitory computer-readable medium of claim 10 , wherein whether or not to use the filter is determined based on a size of the current block.
12. The non-transitory computer-readable medium of claim 10 , wherein the prediction pixel and the reference pixel are located on one horizontal line.