Method and apparatus for encoding of video using depth information

1. An image encoding method using a depth information, comprising:

verifying, by a processor, a depth information of a current coding unit (CU) having a variable size from a depth image:

determining, by the processor, whether the current CU has a single object or not based on a size of the current CU and maximum and minimum depth values included in a depth value distribution information of the current CU;

determining, by the processor, a motion searching range in a total motion searching region for calculating a motion vector of the current CU based on whether the current CU has the single object or not; and

determining, by the processor, an optimum motion vector of the current CU based on a motion information inside the motion searching range.

2. The image encoding method according to claim 1 , wherein an object in the motion searching range is same as an object in the current CU.

3. The image encoding method according to claim 1 , wherein the step of determining the motion searching range includes:

excluding a region, an object of which is not same as the single object of the current CU, among the total motion searching region from the motion searching range when the current CU has the single object.

4. The image encoding method according to claim 1 , wherein the depth information includes four-corner depth values of the current CU.

5. The image encoding method according to claim 1 , wherein when a difference between the maximum depth value and the minimum depth value included in the depth value distribution information of the current CU is less than a reference value, it is determined that the current CU has the single object.

6. An image encoding method using a depth information, comprising:

verifying, by a processor, a total motion searching region for calculating a motion vector of a current coding unit (CU);

determining, by the processor, whether a motion search in a current motion searching location is performed or not according to a size of the current CU and a depth information of the current CU extracted from a depth image, the depth information including four-corner depth values of the current CU; and

determining, by the processor, an optimum motion vector of the current CU based on a result of the step of determining whether the motion search in the current motion searching location is performed or not.

7. The image encoding method according to claim 6 , wherein the step of determining whether the motion search in the current motion searching location is performed or not includes:

determining that the object in the motion searching range is same as the object in the current CU when a difference between a maximum value and a minimum value among the four-corner depth values of the current CU is less than a reference value.

8. The image encoding method according to claim 6 , wherein the step of determining whether the motion search in the current motion searching location is performed or not includes:

storing one of the four-corner depth values when the size of the current CU is greater than a reference value and a difference between a maximum value and a minimum value among the four-corner depth values of the current CU is less than a reference value; and

determining to search a current location when a depth value of a current motion searching location is equal to the stored value and not to search the current location when the depth value of the current motion searching location is different from the stored value.

9. The image encoding method according to claim 6 , wherein the step of determining whether the motion search in the current motion searching location is performed or not includes:

storing one of the four-corner depth values when the size of the current CU is smaller than a reference value and the four-corner depth values of the current CU are same as one another; and

determining to search a current location when a depth value of a current motion searching location is equal to the stored value and not to search the current location when the depth value of the current motion searching location is different from the stored value.

10. An image encoding apparatus using a depth information, comprising:

a processor; and

a memory configured to store instructions executable by the processor,

wherein the processor is configured:

to verify a depth information of a current coding unit (CU) from a depth image;

to determine whether the current CU has a single object or not based on a size of the current CU and maximum and minimum dearth values included in a depth value distribution information of the current CU:

to determine a motion searching range in a total motion searching region for calculating a motion vector of the current CU based on whether the current CU has the single object or not; and

to determine an optimum motion vector of the current CU based on a motion information inside the motion searching range.

11. The image encoding apparatus according to claim 10 , wherein an object in the motion searching range is same as an object in the current CU.

12. The image encoding apparatus according to claim 10 , wherein the processor is configured to exclude a region, an object of which is not same as the single object of the current CU, among the total motion searching region from the motion searching range when the current CU has the single object.

13. The image encoding apparatus according to claim 12 , wherein the depth information includes four-corner depth values of the current CU.

14. An image encoding apparatus using a depth information, comprising:

a processor; and

a memory configured to store instructions executable by the processor,

wherein the processor is configured:

to verify a total motion searching region for calculating a motion vector of a current coding unit (CU);

to determine whether a motion search in a current motion searching location is performed or not according to a size of the current CU and the depth information of the current CU, which is extracted from a depth image, the depth information including four-corner depth values of the current CU; and

to determine an optimum motion vector of the current CU.

15. The image encoding apparatus according to claim 14 , wherein the processor is configured to store one of the four-corner depth values when the size of the current CU is greater than a reference value and a difference between a maximum value and a minimum value among the four-corner depth values of the current CU is less than a reference value, and

wherein the processor is configured to store one of the four-corner depth values of the current CU when the size of the current CU is smaller than a reference value and the four-corner depth values of the current CU are same as one another.

16. The image encoding apparatus according to claim 15 , wherein the processor is configured to determine to search a current location when a depth value of the current motion searching location is equal to the stored value, and the processor is configured to determine not to search the current location when the depth value of the current motion searching location is different from the stored value.

17. The image encoding method according to claim 4 , wherein the step of the determining a motion searching range includes:

determining that the object in the motion searching range is same as the object in the current CU when a difference between a maximum value and a minimum value among the four-corner depth values of the current CU is less than a reference value.