Method of and apparatus for video encoding and decoding based on motion estimation

Abstract

Provided is a method of and apparatus for video encoding and decoding based on motion estimation. The method includes generating a motion vector by searching a reference picture using pixels of a current block, generating a prediction motion vector that is a prediction value of the motion vector by searching the reference picture using previously encoded pixels located adjacent to the current block, and encoding the current block based on the motion vector and the prediction motion vector. By accurately predicting the motion vector of the current block, the number of bits required for encoding the motion vector can be reduced, thereby improving the compression rate of video data.

1 . A method of video encoding, the method comprising:
 generating a first motion vector by searching a reference picture using pixels of a current block;   generating a prediction motion vector that is a prediction value of the first motion vector by searching the reference picture using previously encoded pixels located adjacent to the current block; and   encoding the current block based on the first motion vector and the prediction motion vector.   
     
     
         2 . The method of  claim 1 , wherein the generation of the prediction motion vector comprises generating a differential value between the first motion vector and the prediction motion vector. 
     
     
         3 . The method of  claim 2 , wherein the encoding of the current block comprises encoding a residue between a prediction value of the current block, which is generated by searching the reference picture using the first motion vector, and the current block, and the differential value between the first motion vector and the prediction motion vector. 
     
     
         4 . The method of  claim 1 , wherein the encoding of the current block comprises encoding the current block in a skip mode based on the prediction motion vector. 
     
     
         5 . The method of  claim 4 , wherein the current block includes one of a 16×16 block, an 8×8 block, and a 4×4 block. 
     
     
         6 . The method of  claim 1 , wherein the previously encoded pixels located adjacent to the current block include neighboring pixels located in at least one of a position to the left of, a position above, or a position above and to the left of the current block. 
     
     
         7 . An apparatus for video encoding, the apparatus comprising:
 a motion vector generation unit which generates a first motion vector by searching a reference picture using pixels of a current block;   a prediction motion vector generation unit which generates a prediction motion vector that is a prediction value of the first motion vector by searching the reference picture using previously encoded pixels located adjacent to the current block; and   an encoding unit which encodes the current block based on the first motion vector and the prediction motion vector.   
     
     
         8 . The apparatus of  claim 7 , further comprising a differential value generation unit which generates a differential value between the first motion vector and the prediction motion vector. 
     
     
         9 . The apparatus of  claim 8 , wherein the encoding unit encodes a residue between a prediction value of the current block, which is generated by searching the reference picture using the first motion vector, and the current block, and the differential value between the first motion vector and the prediction motion vector. 
     
     
         10 . The apparatus of  claim 7 , wherein the encoding unit encodes the current block in a skip mode based on the prediction motion vector. 
     
     
         11 . The apparatus of  claim 10 , wherein the current block includes one of a 16×16 block, an 8×8 block, and a 4×4 block. 
     
     
         12 . The apparatus of  claim 7 , wherein the previously encoded pixels located adjacent to the current block include neighboring pixels located in at least one of a position to the left of, a position above, or a position above and to the left of the current block. 
     
     
         13 . A method of video decoding, the method comprising:
 receiving a bitstream including data regarding a current block that has been encoded based on a first motion vector generated by searching a reference picture using pixels of the current block and a prediction motion vector that is a prediction value of the first motion vector and is generated by searching the reference picture using previously encoded pixels located adjacent to the current block;   extracting data regarding the current block and data regarding a differential value between the prediction motion vector and the first motion vector; and   performing motion compensation on the extracted data regarding the current block using the extracted data regarding the differential value motion vector.   
     
     
         14 . The method of  claim 13 , wherein the data regarding the differential value motion vector is a differential value between the first motion vector and the prediction motion vector, and the performing of the motion compensation comprises:
 generating the prediction motion vector by searching the reference picture using previously decoded pixels located adjacent to the current block;   generating the first motion vector by adding the extracted differential value to the prediction motion vector; and   generating a prediction value of the current block using the generated first motion vector.   
     
     
         15 . The method of  claim 14 , wherein the previously decoded pixels located adjacent to the current block include neighboring pixels located in at least one of a position to the left of, a position above, or a position above and to the left of the current block. 
     
     
         16 . The method of  claim 13 , wherein the performing of the motion compensation comprises performing motion compensation on the current block in a skip mode based on the prediction motion vector. 
     
     
         17 . The method of  claim 16 , wherein the current block includes one of a 16×16 block, an 8×8 block, and a 4×4 block. 
     
     
         18 . An apparatus for video decoding, the apparatus comprising:
 a decoding unit which receives a bitstream including data regarding a current block that has been encoded based on a first motion vector generated by searching a reference picture using pixels of the current block and a prediction motion vector that is a prediction value of the first motion vector and is generated by searching the reference picture using previously encoded pixels located adjacent to the current block, and which extracts the data regarding the current block and data regarding a differential value between the prediction motion vector and the first motion vector from the received bitstream; and   a motion compensation unit which performs motion compensation on the extracted data regarding the current block using the extracted data regarding the differential value motion vector.   
     
     
         19 . The apparatus of  claim 18 , wherein the extracted data regarding the differential value motion vector is a differential value between the first motion vector and the prediction motion vector, and the motion compensation unit comprises:
 a prediction motion vector generation unit which generates the prediction motion vector by searching a reference picture using previously decoded pixels located adjacent to the current block;   a motion vector generation unit which generates the first motion vector by adding the extracted differential value to the prediction motion vector; and   a motion compensation performing unit which generates a prediction value of the current block using the generated first motion vector.   
     
     
         20 . The apparatus of  claim 19 , wherein the previously decoded pixels located adjacent to the current block include neighboring pixels located in at least one of a position to the left of, a position above, or a position above and to the left of the current block. 
     
     
         21 . The apparatus of  claim 18 , wherein the motion compensation performing unit performs motion compensation on the current block in a skip mode based on the prediction motion vector. 
     
     
         22 . The apparatus of  claim 18 , wherein the current block includes one of a 16×16 block, an 8×8 block, and a 4×4 block. 
     
     
         23 . A computer-readable recording medium having recorded thereon a program for implementing the method of  claim 1 .