A video encoding method comprising: encoding a frame having a 360-degree image content represented by projection faces (P1,..., P8) arranged in a 360-degree Virtual Reality, 360 VR, projection layout to generate a bitstream, wherein the projection faces (P1,..., P8) comprise a plurality of triangular projection faces; and signaling a first syntax element via the bitstream; characterized in that when a predefined projection layout is selected and used as the 360 VR projection layout, the first syntax element is set to indicate selection of the predefined projection layout, and the video encoding method further comprises: selecting the predefined projection layout from a set of different predefined projection layouts (S1,..., SN) with fixed projection layout configurations, and setting the 360 VR projection layout by the predefined projection layout; and when a predefined projection layout is not selected and used as the 360 VR projection layout, the first syntax element is set to indicate unselection of a predefined projection layout, and the video encoding method further comprises: setting a 360 VR projection layout, comprising triangular projection faces (P1,..., P8) located at a plurality of positions in the 360 VR projection layout respectively, and for each position, signaling at least one second syntax element via the bitstream, wherein the at least one second syntax element is set to indicate at least one of an index of a triangular projection view filled into a corresponding triangular projection face (P1,..., P8) located at said each position and a rotation angle of content rotation applied to the triangular projection view filled into the corresponding triangular projection face (P1,..., P8) located at said each position. encoding a frame having a 360-degree image content represented by projection faces (P1,..., P8) arranged in a 360-degree Virtual Reality, 360 VR, projection layout to generate a bitstream, wherein the projection faces (P1,..., P8) comprise a plurality of triangular projection faces; and signaling a first syntax element via the bitstream; characterized in that when a predefined projection layout is selected and used as the 360 VR projection layout, the first syntax element is set to indicate selection of the predefined projection layout, and the video encoding method further comprises: selecting the predefined projection layout from a set of different predefined projection layouts (S1,..., SN) with fixed projection layout configurations, and setting the 360 VR projection layout by the predefined projection layout; and selecting the predefined projection layout from a set of different predefined projection layouts (S1,..., SN) with fixed projection layout configurations, and setting the 360 VR projection layout by the predefined projection layout; and when a predefined projection layout is not selected and used as the 360 VR projection layout, the first syntax element is set to indicate unselection of a predefined projection layout, and the video encoding method further comprises: setting a 360 VR projection layout, comprising triangular projection faces (P1,..., P8) located at a plurality of positions in the 360 VR projection layout respectively, and for each position, signaling at least one second syntax element via the bitstream, wherein the at least one second syntax element is set to indicate at least one of an index of a triangular projection view filled into a corresponding triangular projection face (P1,..., P8) located at said each position and a rotation angle of content rotation applied to the triangular projection view filled into the corresponding triangular projection face (P1,..., P8) located at said each position. setting a 360 VR projection layout, comprising triangular projection faces (P1,..., P8) located at a plurality of positions in the 360 VR projection layout respectively, and for each position, signaling at least one second syntax element via the bitstream, wherein the at least one second syntax element is set to indicate at least one of an index of a triangular projection view filled into a corresponding triangular projection face (P1,..., P8) located at said each position and a rotation angle of content rotation applied to the triangular projection view filled into the corresponding triangular projection face (P1,..., P8) located at said each position.