Image data encoding/decoding method and apparatus

Abstract

Disclosed are methods and apparatuses for image data encoding/decoding. A method of decoding a 360-degree image includes receiving a bitstream in which the 360-degree image is encoded; generating a predicted image with reference to syntax information acquired from the received bitstream; acquiring a decoded image by combining the generated predicted image with a residual image acquired by inversely quantizing and inversely transforming the bitstream; and reconstructing the decoded image into the 360-degree image according to a projection format. Here, the generating of the predicted image includes generating a prediction block of a current block to be decoded using a reference region that is included within at least one reference picture and is set in a region having image continuity between faces according to the projection format, by referring to motion information obtained from the syntax information.

What is claimed is: 
     
         1 . A method of decoding a 360-degree image, the method comprising:
 receiving a bitstream in which the 360-degree image is encoded;   generating a predicted image with reference to syntax information acquired from the received bitstream;   acquiring a decoded image by combining the generated predicted image with a residual image acquired by inversely quantizing and inversely transforming the bitstream; and   reconstructing the decoded image into the 360-degree image according to a projection format,   wherein the generating of the predicted image comprises:
 generating a prediction block of a current block to be decoded using a reference region that is included within at least one reference picture and is set in a region having image continuity between faces according to the projection format, by referring to motion information obtained from the syntax information. 
   
     
     
         2 . The method of  claim 1 , wherein the reference picture is expanded in up, down, left, and right directions on the basis of image continuity according to the projection format, and then the reference region is set. 
     
     
         3 . The method of  claim 1 , wherein the reference picture is expanded in a face unit, and the reference region is set over the face boundary.