ilm_grain_characteristics_cancel_flag equal to 0 indicates that film grain modelling information follows. model id identifies the film grain simulation model as specified in Table D-5. The value of model id shall be in the range of 0 to 1, inclusive. The values of 2 and 3 for model id are reserved for future use by ITU-T ISO/IEC. Decoders shall ignore film grain characteristic SEI messages with model_id equal to 2 or 3. Table D-5 - model_id values Value Description frequency filtering auto-regression reserved reserved separate_colour_description_present_flagequal to 1 indicates that a distinct colour space description for the film grain characteristics specified in the SEI message is present in the film grain characteristics SEI message syntax. separate_colour_description_present_flag equal to 0 indicates that the colour description for the film grain characteristics specified in the SEI message is the same as for the coded video sequence as specified in clause E.2.1. NOTE 3 - When separate_colour_description_present_flag is equal to 1, the colour space specified for the film grain characteristics specified in the SEI message may differ from the colour space specified for the coded video as specified in clause E.2.1. film_grain_bit_depth_luma_minus8 plus 8 specifies the bit depth used for the luma component of the film grain characteristics specified in the SEI message. When film_grain_bit_depth_luma_minus8 is not present in the film grain characteristics SEI message, the value of film_grain_bit_depth_luma_minus8 shall be inferred to be equal to bit_depth_luma_minus8. The value of filmGrainBitDepth| 0] is derived as filmGrainBitDepth[0]=film_grain_bit_depth_luma_minus8+ (D-14) ilm_grain_bit_depth_chroma_minus8 plus 8 specifies the bit depth used for the Cb and Cr components of the film grain characteristics specified in the SEI message. When film_grain_bit_depth_chroma_minus8 is not present in the film grain characteristics SEI message, the value of film_grain_bit_depth_chroma_minus8 shall be inferred to be equal