A method of decoding video data comprising: decoding a video block of a video frame using one of a unidirectional prediction mode with respect to a reference picture in a first reference picture list (94, 96) or a bidirectional prediction mode with respect to a reference picture in the first reference picture list and a reference picture in a second reference picture list (94, 96); and decoding a syntax element indicating that the video block is decoded using the one of the unidirectional prediction mode with respect to the reference picture in the first reference picture list or the bidirectional prediction mode, characterized in that the method further comprises: comparing the first reference picture list (94, 96) and the second reference picture list (94, 96); and determining that the video frame is coded as a generalized P/B frame when the first reference picture list and the second reference picture list are identical, wherein only the first reference picture list is used when the video block is decoded using the unidirectional prediction mode; and wherein decoding the syntax element comprises decoding a single bit syntax element indicating that the video block is decoded using the one of the unidirectional prediction mode or the bidirectional prediction mode, without indicating the reference picture list used for the unidirectional prediction mode. decoding a video block of a video frame using one of a unidirectional prediction mode with respect to a reference picture in a first reference picture list (94, 96) or a bidirectional prediction mode with respect to a reference picture in the first reference picture list and a reference picture in a second reference picture list (94, 96); and decoding a syntax element indicating that the video block is decoded using the one of the unidirectional prediction mode with respect to the reference picture in the first reference picture list or the bidirectional prediction mode, characterized in that the method further comprises: comparing the first reference picture list (94, 96) and the second reference picture list (94, 96); and determining that the video frame is coded as a generalized P/B frame when the first reference picture list and the second reference picture list are identical, wherein only the first reference picture list is used when the video block is decoded using the unidirectional prediction mode; and wherein decoding the syntax element comprises decoding a single bit syntax element indicating that the video block is decoded using the one of the unidirectional prediction mode or the bidirectional prediction mode, without indicating the reference picture list used for the unidirectional prediction mode. comparing the first reference picture list (94, 96) and the second reference picture list (94, 96); and determining that the video frame is coded as a generalized P/B frame when the first reference picture list and the second reference picture list are identical, wherein only the first reference picture list is used when the video block is decoded using the unidirectional prediction mode; and wherein decoding the syntax element comprises decoding a single bit syntax element indicating that the video block is decoded using the one of the unidirectional prediction mode or the bidirectional prediction mode, without indicating the reference picture list used for the unidirectional prediction mode.