Patent ID: 11863732
Assignee: B1 INSTITUTE OF IMAGE TECHNOLOGY, INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 0:
1. A method of decoding a 360-degree image performed by an image decoding apparatus, the method comprising:
receiving a bitstream in which the 360-degree image is encoded, the bitstream including data of an expanded 2-dimensional image, the expanded 2-dimensional image including a 2-dimensional image and a predetermined expansion region, and the 2-dimensional image being projected from an image with a 3-dimensional projection structure and including one or more faces;
generating a predicted image by performing prediction based on information on the prediction included in the bitstream; and
reconstructing the expanded 2-dimensional image based on the predicted image and a residual image,
wherein sample values of the expansion region are determined by changing sample values of the face for the sample values of the expansion region,
wherein a size of the expansion region is determined based on size information obtained from the bitstream,
wherein the predicted image is generated by performing inter prediction, and
wherein the 3-dimensional projection structure is selectively determined based on identification information, among a plurality of pre-defined 3-dimensional projection structures including a first 3-dimensional projection structure and a second 3-dimensional projection structure, the identification information being obtained from the bitstream,
wherein existence information indicating existence of the expansion region is obtained from the bitstream,
wherein the size information for the expansion region is obtained from the bitstream in case the existence information indicates that the expansion region exists,
wherein, based on a projection format for the 3-dimensional projection structure is a first projection format, the size of the expansion region is determined based on first width information for specifying a width of the expansion region on a left side of the face and second width information for specifying a width of the expansion region on a right side of the face, both the first width information and the second width information being obtained from the bitstream,
wherein, based on a projection format for the 3-dimensional projection structure is a second projection format, the size of the expansion region is determined based on first width information for specifying a width of the expansion region on a left side of the face, second width information for specifying a width of the expansion region on a right side of the face, third height information for specifying a height of the expansion region on a top side of the face and fourth height information for specifying a height of the expansion region on a bottom side of the face, all of the first width information, the second width information, the third height information and the fourth height information being obtained from the bitstream.