Method and apparatus for encoding and decoding a large field of view video

A method for decoding a bitstream representative of a large field of view video, at least one picture of said large field of view video being represented as a surface, said surface being projected onto at least one 2D picture using a projection function, said method comprising, for at least one current block of said at least one 2D picture coded according to a current intra prediction mode m:

• determining from said projection function, at least one neighbor block of said 2D picture, called first neighbor block C, not spatially adjacent to said current block in said 2D picture, said at least one neighbor block being spatially adjacent to said current block on said surface,
• determining a list of most probable modes based on an intra prediction mode m_C of said first neighbor block C and further based on at least an intra prediction mode m_A of a second neighbor block A and on an intra prediction mode m_B of a third neighbor block B, said second and third neighbor blocks being spatially adjacent to said current block in said 2D picture;
• and
• decoding said current intra prediction mode from said list of most probable modes.

An apparatus for decoding a bitstream representative of a large field of view video, at least one picture of said large field of view video being represented as a surface, said surface being projected onto at least one 2D picture using a projection function, said apparatus comprising one or more processors configured to:

• determine from said projection function, for at least one current block of said at least one 2D picture coded according to a current intra prediction mode m, at least one neighbor block of said 2D picture, called first neighbor block C, not spatially adjacent to said current block in said 2D picture, said at least one neighbor block being spatially adjacent to said current block on said surface,
• determine a list of most probable modes based on an intra prediction mode m_C of said first neighbor block C and further based on at least an intra prediction mode m_A of a second neighbor block A and on an intra prediction mode m_B of a third neighbor block B, said second and third neighbor blocks being spatially adjacent to said current block in said 2D picture;
• and
• decode said current intra prediction mode from said list of most probable modes.