Method and apparatus for processing video signal
A method for decoding a video according to the present invention may comprise: deriving a reference sample for a current block, determining an intra prediction mode of the current block, and obtaining a prediction sample for the current block by using the reference sample and the intra prediction mode.
1. A method for decoding a video, the method comprising:
determining an intra prediction mode of a current block; and
obtaining a prediction sample for the current block based on a weighted sum of a first prediction sample and a second prediction sample when the intra prediction mode is Planar mode,
the first prediction sample being obtained by using at least one reference sample located on a same horizontal line as a prediction target sample and the second prediction sample being obtained by using at least one reference sample located on a same vertical line as the prediction target sample,
wherein if the prediction sample is included in a first region of the current block, the prediction sample is obtained by further usage of a first value derived by a weighted sum of a top reference sample and a left reference sample, and
wherein if the prediction sample is included in a second region of the current block, the prediction sample is obtained by further usage of a second value derived by one of the top reference sample and the left reference sample.
2. The method of claim 1 ,
wherein the at least one reference sample located on the same horizontal line as the prediction sample comprises a right reference sample derived based on the left reference sample and the top reference sample, and
wherein the at least one reference sample located on the same vertical line as the prediction sample comprises a bottom reference sample derived based on the top reference sample and the left reference sample.
3. The method of claim 1 , wherein the prediction sample is obtained based on a weighted sum of the first prediction sample and the second prediction sample.
4. A method for encoding a video, the method comprising:
determining an intra prediction mode of a current block; and
obtaining a prediction sample for the current block based on a weighted sum of a first prediction sample and a second prediction sample when the intra prediction mode is Planar mode,
the first prediction sample being obtained by using at least one reference sample located on a same horizontal line as a prediction target sample and a second prediction sample being obtained by using at least one reference sample located on a same vertical line as the prediction target sample,
wherein if the prediction sample is included in a first region of the current block, the prediction sample is obtained by further usage of a first value derived by a weighted sum of a top reference sample and a left reference sample, and
wherein if the prediction sample is included in a second region of the current block, the prediction sample is obtained by further usage of a second value derived by one of the top reference sample and the left reference sample.
5. The method of claim 4 ,
wherein the at least one reference sample located on the same horizontal line as the prediction sample comprises a right reference sample derived based on the left reference sample and the top reference sample, and
wherein the at least one reference sample located on the same vertical line as the prediction sample comprises a bottom reference sample derived based on the top reference sample and the left reference sample.
6. The method of claim 4 , wherein the prediction sample is obtained based on a weighted sum of the first prediction sample and the second prediction sample.
7. A non-transitory computer-readable medium for storing data associated with a video signal, comprising:
a data stream stored in the non-transitory computer-readable medium, the data stream being encoded by an encoding method which comprising:
determining an intra prediction mode of a current block; and
obtaining a prediction sample for the current block based on a weighted sum of a first prediction sample and a second prediction sample when the intra prediction mode is Planar mode, the first prediction sample being obtained by using at least one reference sample located on a same horizontal line as a prediction target sample and a second prediction sample being obtained by using at least one reference sample located on a same vertical line as the prediction target sample,
wherein if the prediction sample is included in a first region of the current block, the prediction sample is obtained by further usage of a first value derived by a weighted sum of a top reference sample and a left reference sample, and
wherein if the prediction sample is included in a second region of the current block, the prediction sample is obtained by further usage of a second value derived by one of the top reference sample and the left reference sample.