Method for deriving a temporal predictive motion vector, and apparatus using the method

Abstract

Disclosed are a method for deriving a temporal predictive motion vector, and an apparatus using the method. An image decoding method may comprise the steps of: determining whether or not a block to be predicted is brought into contact with a boundary of a largest coding unit (LCU); and determining whether or not a first call block is available according to whether or not the block to be predicted is brought into contact with the boundary of the LCU. Accordingly, unnecessary memory bandwidth may be reduced, and implementation complexity may also be reduced.

1 - 20 . (canceled) 
     
     
         21 . A method of decoding a video signal with a decoding apparatus, comprising:
 obtaining a spatial prediction motion vector of a current block using a motion vector of a spatial neighboring block adjacent to the current block;   determining a collocated block in a collocated picture based on a position of the current block in a largest coding unit;   obtaining a temporal prediction motion vector of the current block using a motion vector of the collocated block;   generating a motion vector candidate list of the current block, the motion vector candidate list including the spatial prediction motion vector and the temporal prediction motion vector; and   performing inter prediction of the current block based on the generated motion vector candidate list.   
     
     
         22 . The method of  claim 21 , wherein the collocated picture is determined based on a collocated reference index which is extracted from the video signal, the collocated reference index indicating a reference index of a picture including the collocated block. 
     
     
         23 . The method of  claim 21 , wherein the collocated block is determined based on whether a boundary of the current block adjoins a boundary of the largest coding unit. 
     
     
         24 . The method of  claim 23 , wherein the adjoined boundary of the current block and the largest coding unit is a bottom boundary. 
     
     
         25 . The method of  claim 21 , wherein the temporal prediction motion vector is obtained by scaling the motion vector of the collocated block. 
     
     
         26 . The method of  claim 25 , the motion vector of the collocated block is scaled based on a temporal distance between a current picture including the current block and a reference picture of the current block. 
     
     
         27 . The method of  claim 25 , wherein the motion vector of the collocated block is scaled based on a temporal distance between the collocated picture and a reference picture of the collocated block. 
     
     
         28 . The method of  claim 25 , wherein the motion vector of the collocated block is scaled based on a first temporal distance and a second temporal distance, the first temporal distance being a temporal distance between a current picture including the current block and a reference picture of the current block, the second temporal distance being a temporal distance between the collocated picture and a reference picture of the collocated block. 
     
     
         29 . The method of  claim 21 , wherein the spatial neighboring block is one of a left neighboring block, a left-bottom neighboring block, a top neighboring block, a top-right neighboring block and a top-left neighboring block. 
     
     
         30 . An apparatus of decoding a video signal, comprising:
 an inter prediction unit configured to obtain a spatial prediction motion vector of a current block using a motion vector of a spatial neighboring block adjacent to the current block, configured to determine a collocated block in a collocated picture based on a position of a current block in a largest coding unit, configured to obtain a temporal prediction motion vector of the current block using a motion vector of the collocated block, configured to generate a motion vector candidate list of the current block, the motion vector candidate list including the spatial prediction motion vector and the temporal prediction motion vector, and configured to perform an inter prediction of the current block based on the generated motion vector candidate list.   
     
     
         31 . The apparatus of  claim 30 , wherein the collocated picture is determined based on a collocated reference index which is extracted from the video signal, the collocated reference index indicating a reference index of a picture including the collocated block. 
     
     
         32 . The apparatus of  claim 30 , wherein the collocated block is determined based on whether a boundary of the current block adjoins a boundary of the largest coding unit. 
     
     
         33 . The apparatus of  claim 32 , wherein the adjoined boundary of the current block and the largest coding unit is a bottom boundary. 
     
     
         34 . The apparatus of  claim 30 , wherein the temporal prediction motion vector is obtained by scaling the motion vector of the collocated block. 
     
     
         35 . The apparatus of  claim 34 , the motion vector of the collocated block is scaled based on a temporal distance between a current picture including the current block and a reference picture of the current block. 
     
     
         36 . The apparatus of  claim 32 , wherein the motion vector of the collocated block is scaled based on a temporal distance between the collocated picture and a reference picture of the collocated block. 
     
     
         37 . The apparatus of  claim 32 , wherein the motion vector of the collocated block is scaled based on a first temporal distance and a second temporal distance, the first temporal distance being a temporal distance between a current picture including the current block and a reference picture of the current block, the second temporal distance being a temporal distance between the collocated picture and a reference picture of the collocated block. 
     
     
         38 . The apparatus of  claim 30 , wherein the spatial neighboring block is one of a left neighboring block, a left-bottom neighboring block, a top neighboring block, a top-right neighboring block and a top-left neighboring block.