Method and apparatus for decoding video signal
A method and apparatus for decoding a video signal are disclosed. A method for decoding a video signal includes obtaining block type information of a current block, confirming a prediction mode of the current block based on the block type information, obtaining, if the prediction mode of the current block is an intra prediction mode according to the prediction mode, at least one correlation parameter information using at least one neighboring pixel of the current block, obtaining an intra prediction value of the current block using the correlation parameter information, and reconstructing the current block using the intra prediction value of the current block.
1. A method for decoding a video signal by a decoding apparatus, the method comprising:
obtaining, by the decoding apparatus, intra prediction mode information of a current block from the video signal;
when the intra prediction mode information indicates a vertical prediction mode, obtaining, by the decoding apparatus, a prediction value of a pixel in the current block using a value of a top neighboring pixel adjacent to the current block and a difference between a value of a top-left neighboring pixel adjacent to the current block and a value of a left neighboring pixel adjacent to the current block, the pixel in the current block having a same x-coordinate as the top neighboring pixel; and
decoding, by the decoding apparatus, the current block based on the obtained prediction value.
2. The method of claim 1 , wherein obtaining the prediction value of the pixel in the current block includes obtaining correlation parameter information from the difference between the value of the top-left neighboring pixel and the value of the left neighboring pixel, and
wherein the prediction value of the pixel in the current block is obtained using the value of the top neighboring pixel and the correlation parameter information.
3. The method of claim 2 , wherein the prediction value of the pixel in the current block is obtained by adding the value of the correlation parameter information to the value of the top neighboring pixel.
4. The method of claim 1 , wherein decoding the current block includes:
obtaining, by the decoding apparatus, residual information of the current block, and
reconstructing, by the decoding apparatus, the pixel in the current block using the residual information and the prediction value of the pixel in the current block.
5. The method of claim 1 , wherein the left neighboring pixel has a same y-coordinate as the pixel in the current block.
6. The method of claim 1 , wherein the left neighboring pixel corresponds to a left neighboring pixel adjacent to a left-bottom corner pixel of the current block.
7. The method of claim 2 , wherein the correlation parameter information is obtained by the following equation:
a
=
L
-
M
4
,
where α denotes the correlation parameter information, L denotes a value of a left neighboring pixel adjacent to a left-bottom corner pixel of the current block, and M denotes the value of the top-left neighboring pixel of the current block.
8. The method of claim 1 , wherein the current block is one of a 16×16 block, an 8×8 block, or a 4×4 block.
9. An apparatus configured to decode a video signal, the apparatus comprising:
a decoding apparatus configured to:
obtain intra prediction mode information of a current block from the video signal;
when the intra prediction mode information indicates a vertical prediction mode, obtain a prediction value of a pixel in the current block using a value of a top neighboring pixel adjacent to the current block and a difference between a value of a top-left neighboring pixel adjacent to the current block and a value of a left neighboring pixel adjacent to the current block, the pixel in the current block having a same x-coordinate as the top neighboring pixel; and
decode the current block based on the obtained prediction value.
10. The apparatus of claim 9 , wherein obtaining the prediction value of the pixel in the current block includes obtaining correlation parameter information from the difference between the value of the top-left neighboring pixel and the value of the left neighboring pixel, and
wherein the prediction value of the pixel in the current block is obtained using the value of the top neighboring pixel and the correlation parameter information.
11. The apparatus of claim 10 , wherein the prediction value of the pixel in the current block is obtained by adding a value of the correlation parameter information to the value of the top neighboring pixel.
12. The apparatus of claim 9 , wherein decoding the current block comprises:
obtaining residual information of the current block, and
reconstructing the pixel in the current block using the residual information and the prediction value of the pixel in the current block.
13. The apparatus of claim 9 , wherein the left neighboring pixel has a same y-coordinate as the pixel in the current block.
14. The apparatus of claim 9 , wherein the left neighboring pixel corresponds to a left neighboring pixel adjacent to a left-bottom corner pixel of the current block.
15. The apparatus of claim 10 , wherein the correlation parameter information is obtained by the following equation:
a
=
L
-
M
4
,
where α denotes the correlation parameter information, L denotes a value of a left neighboring pixel adjacent to a left-bottom corner pixel of the current block, and M denotes the value of the top-left neighboring pixel of the current block.
16. The apparatus of claim 9 , wherein the current block is one of a 16×16 block, an 8×8 block, or a 4×4 block.