A method of decoding video data from a bitstream, the bitstream comprising video data corresponding to one or more slices. The bitstream comprises a picture header comprising syntax elements to be used when decoding one or more slices, and a slice header comprising syntax elements to be used when decoding a slice. In the picture header at least one syntax element indicating whether a decoding tool may be used in the picture. When the decoding tool is used in the picture, at least one APS ID related syntax element is parsed for the decoding tool in the picture header. The decoding also comprises parsing, in a slice header, at least one syntax element indicating whether the decoding tool is to be used or not for that slice prior to syntax elements relating to other decoding tools. A bitstream is decoded using said syntax elements.