A method of decoding a bitstream in binary format for scene, BIFS, into which a coordinate interpolator that comprises key value data and a key value header comprising information regarding the key value data is encoded, the key value data representing the shape and position of an object on a key frame using coordinates of each of a plurality of vertices comprising x, y, and z components, the method comprising: (a) decoding the key value header; and (b) decoding the key value data according to the result of the decoding performed in (a), wherein (b) comprises: entropy-decoding the key value data in units of the x, y, and z components; dictionary-decoding the entropy-decoded key value data in units of the x, y, and z components; inversely differential-pulse-code-modulating the dictionary-decoded key value data in units of the x, y, and z components; and inversely quantizing the inversely differential-pulse-code modulated key value data in units of the x, y, and z components, characterised in that the key value header comprises a transpose flag (bTranspose) which indicates whether the key value data is to be decoded in a vertex mode wherein the key value data is not transposed, or in a transpose mode, wherein (b) further comprises determining whether the transpose flag indicates that the key value data is to be decoded in the vertex mode or in the transpose mode and transposing the result of the inversely quantizing if the transpose flag is determined to indicate that the key value data is to be decoded in the transpose mode. (a) decoding the key value header; and (b) decoding the key value data according to the result of the decoding performed in (a), wherein (b) comprises: entropy-decoding the key value data in units of the x, y, and z components; dictionary-decoding the entropy-decoded key value data in units of the x, y, and z components; inversely differential-pulse-code-modulating the dictionary-decoded key value data in units of the x, y, and z components; and inversely quantizing the inversely differential-pulse-code modulated key value data in units of the x, y, and z components, characterised in that the key value header comprises a transpose flag (bTranspose) which indicates whether the key value data is to be decoded in a vertex mode wherein the key value data is not transposed, or in a transpose mode, wherein (b) further comprises determining whether the transpose flag indicates that the key value data is to be decoded in the vertex mode or in the transpose mode and transposing the result of the inversely quantizing if the transpose flag is determined to indicate that the key value data is to be decoded in the transpose mode. entropy-decoding the key value data in units of the x, y, and z components; dictionary-decoding the entropy-decoded key value data in units of the x, y, and z components; inversely differential-pulse-code-modulating the dictionary-decoded key value data in units of the x, y, and z components; and inversely quantizing the inversely differential-pulse-code modulated key value data in units of the x, y, and z components, characterised in that the key value header comprises a transpose flag (bTranspose) which indicates whether the key value data is to be decoded in a vertex mode wherein the key value data is not transposed, or in a transpose mode, wherein (b) further comprises determining whether the transpose flag indicates that the key value data is to be decoded in the vertex mode or in the transpose mode and transposing the result of the inversely quantizing if the transpose flag is determined to indicate that the key value data is to be decoded in the transpose mode.