Method and device for encoding or decoding image by means of view merging prediction

1. An image decoding method, performed by a decoding apparatus comprising a processor, the method comprising:

determining at least one prediction unit included in a current coding unit that is one of at least one coding unit splitting the image;

generating a merge candidate list related to a current prediction unit included in the at least one prediction unit;

determining a prediction mode to be performed in the current prediction unit based on the merge candidate list;

performing prediction according to the determined prediction mode: and

reconstructing the current prediction unit based on the prediction results,

wherein the generating of the merge candidate list further comprises:

adding a neighboring prediction unit adjacent to the current prediction unit to the merge candidate list based on a fist information indicating availability of the neighboring prediction unit as a spatial merging candidate; and

determining whether to add a view synthesis prediction merging candidate to the merge candidate list based on the first information indicating the availability of the neighboring prediction unit as the spatial merging candidate, a second information indicating availability of the view synthesis prediction merging candidate for the current prediction unit and a third information indicating whether the neighboring prediction unit is coded according to a view synthesis prediction,

wherein the prediction mode to be performed in the current prediction unit is determined as the view synthesis prediction when it is determined the view synthesis prediction merging candidate is available for the current prediction unit based on the second information, it is determined the neighboring prediction unit is coded according to the view synthesis prediction based on the third information and it is determined a merge candidate to be used for the current prediction unit is the neighboring prediction unit.

2. The image decoding method of claim 1 , wherein the neighboring prediction unit is adjacent to a left side of the current prediction unit among spatial merging candidates.

3. The image decoding method of claim 1 , wherein, when it is determined the view synthesis prediction merging candidate is available for the current prediction unit and when the neighboring prediction unit is unavailable as the spatial merging candidate or the neighboring prediction unit is not coded according to the view synthesis prediction, generating the merge candidate list including the view synthesis prediction merging candidate.

4. The image decoding method of claim 3 , wherein, when it is determined the view synthesis prediction merging candidate is available for the current prediction unit and when the neighboring prediction unit is unavailable as the spatial merging candidate or the neighboring prediction unit is not coded according to the view synthesis prediction, adding the view synthesis prediction merging candidate to the merge candidate list after the neighboring prediction unit adjacent to a left side of the current prediction unit and a neighboring prediction unit adjacent to an upper end of the current prediction unit among spatial merging candidates are added to the merge candidate list.

5. An image decoding apparatus comprising a processor, the apparatus comprising:

a decoder configured to determine at least one prediction unit included in a current coding unit that is one of at least one coding unit splitting the image, generate a merge candidate list related to a current prediction unit included in the at least one prediction unit, determine a prediction mode to be performed in the current prediction unit based on the merge candidate list, perform prediction according to the determined prediction mode and reconstruct the current prediction unit based on the prediction results,

wherein the decoder is further configured to:

add a neighboring prediction unit adjacent to the current prediction unit to the merge candidate list based on a first information indicating availability of the neighboring prediction unit as a spatial merging candidate; and

determine Whether to add a view synthesis prediction merging candidate to the merge candidate list based on the first information indicating the availability of the neighboring prediction unit as the spatial merging candidate, a second information indicating availability of the view synthesis prediction merging candidate for the current prediction unit and a third information indicating whether the neighboring prediction unit is coded according to a view synthesis prediction,

wherein the decoder is further configured to determine the prediction mode to be performed in the current prediction unit as the view synthesis prediction when it is determined the view synthesis prediction merging candidate is available for the current prediction unit based on the second information, it is determined the neighboring prediction unit is coded according to the view synthesis prediction based on the third information and it is determined a merge candidate to be used for the current prediction unit is the neighboring prediction unit.

6. The image decoding apparatus of claim 5 , wherein the neighboring prediction unit is adjacent to a left side of the current prediction unit among spatial merging candidates.

7. The image decoding apparatus of claim 5 , wherein, when it is determined the view synthesis prediction merging candidate is available for the current prediction unit and when the neighboring prediction unit is unavailable as the spatial merging candidate or the neighboring prediction unit is not coded according to the view synthesis prediction, the decoder is further configured to generate the merge candidate list including the view synthesis prediction merging candidate.

8. The image decoding apparatus of claim 7 , wherein, when it is determined the view synthesis prediction merging candidate is available for the current prediction unit and when the neighboring prediction unit is unavailable as the spatial merging candidate or the neighboring prediction unit is not coded according to the view synthesis prediction, the decoder is further configured to add the view synthesis prediction merging candidate to the merge candidate list after the neighboring prediction unit adjacent to a left side of the current prediction unit and a neighboring prediction unit adjacent to an upper end of the current prediction unit among spatial merging candidates are added to the merge candidate list.

9. A non-transitory computer-readable recording medium having recorded thereon a program for performing the image decoding method of claim 1 .