Method and apparatus for generating encoded motion information/recovering motion information using motion information integration, and image encoding/decoding method and apparatus using same

1. An apparatus for encoding a current block, the apparatus comprising: an inter prediction unit configured to generate a plurality of motion vector candidates of the current block from neighboring blocks of the current block, and decide whether a motion vector of the current block is set as one of the plurality of motion vector candidates, generate a first identification information indicating whether the motion vector of the current block is set as one of the plurality of motion vector candidates, and generate, when the motion vector of the current block is set as one of the plurality of motion vector candidates, a second identification information for identifying one of the plurality of motion vector candidates, wherein the first identification information indicates that the motion vector of the current block is set as one of the plurality of motion vector candidates; a subtraction unit configured to generate a residual block by subtracting a predicted block of the current block from the current block, wherein the predicted block has been generated by using the motion vector of the current block; a transform and quantization unit configured to frequency-transform and quantize the residual block so as to generate a quantized frequency residual block; and an encoding unit configured to encode the quantized frequency residual block and the quantized frequency residual block and the first identification information, and encode the second identification information when the motion vector of the current block is set as one of the plurality of motion vector candidates.

2. The apparatus of claim 1 , wherein the plurality of motion vector candidates are generated by using motion vectors of the neighboring blocks of the current block.

3. The apparatus of claim 2 , wherein the neighboring blocks include a neighboring block including a sample located just above a left sample of a top-left sample of the current block, and a neighboring block including a sample located on a right side just above a top-right sample of the current block.

4. The apparatus of claim 1 , wherein when the motion vector of the current block is not set as any of the plurality of motion vector candidates: the inter prediction unit is further configured to calculate a predicted motion vector of the current block, and generate a differential motion vector between the predicted motion vector and the motion vector of the current block, wherein the first identification information indicates that the motion vector of the current block is not set as any of the plurality of motion vector candidates; and the encoding unit is further configured to encode the differential motion vector.

5. A method for decoding a current block, the method performed by a video decoding apparatus and comprising: extracting a first identification information from a bitstream, wherein the first identification information indicates whether a motion vector of the current block is set as one of a plurality of motion vector candidates; when the first identification information indicates that the motion vector of the current block is set as one of the plurality of motion vector candidates, performing the following steps: generating the plurality of motion vector candidates of the current block from neighboring blocks of the current blocks, decoding, from the bitstream, a second identification information for identifying one of the plurality of motion vector candidates, selecting a motion vector candidate from the plurality of motion vector candidates based on the second identification information, reconstructing the motion vector of the current block as the selected motion vector candidate, and generating a predicted block of the current block by using the reconstructed motion vector of the current block; reconstructing a quantized frequency residual block of the current block from the bitstream; dequantizing and inversely transforming the quantized frequency residual block to reconstruct a residual block of the current block; and adding the predicted block to the reconstructed residual block to reconstruct the current block.

6. The method of claim 5 , further comprising: when the first identification information indicates that the motion vector of the current block is not set as any of the plurality of motion vector candidates, generating a predicted block of the current block by using a decoded motion vector of the current block, wherein the decoded motion vector of the current block has been extracted from the bitstream and decoded.

7. The video decoding method of claim 5 , wherein the plurality of motion vector candidates are generated by using motion vectors of the neighboring blocks of the current block.

8. The method of claim 7 , wherein the neighboring blocks include a neighboring block including a sample located just above a left sample of a top-left sample of the current block, and neighboring blocks including a sample located on a right side just above a top-right sample of the current block.