pli- Y = 0.183R + 0.614G' + 0.062B + 16 cations. For every four horizontal Y samples, there is one Cb = -0.101R' - 0.338G' + 0.439B + 128 Cb and Cr value. Each component is typically 8 bits. Each Cr = 0.439R' - 0.399G' - 0.040B' + 128 sample therefore requires 12 bits, usually formatted as shown in Figure 7.2-6. R' = 1.164(Y - 16) + 1.793 (Cr - 128) To display 4:1:1 YCbCr data, it is first converted to G' = 1.164(Y - 16) - 0.534(Cr - 128) 4:4:4 YCbCr data, using interpolation to generate the - 0.213(Cb - 128) missing Cb and Cr samples. B' = 1.164(Y - 16) + 2.115(Cb - 128) Note that 8-bit YCbCr and R'G'B' data should be saturated at the 0 and 255 levels to avoid underflow and ACTIVE X = FIELD 1 (576i FIELD 2) overflow wrap-around problems. [X] = FIELD 2 (576i FIELD 1) NUMBER 4:4:4 YCbCr Format Figure 7.2-2 illustrates the positioning of YCbCr samples for the 4:4:4 format. Each sample has a Y, a Cb, and a Cr value. Each sample is typically 8 bits (consumer appli- cations) or 10 bits (pro-video applications) per compo- nent. Each sample therefore requires 24 bits (or 30 bits for pro-video applications). CB, CR SAMPLE 4:2:2 YCbCr Format Y SAMPLE Figure 7.2-3 illustrates the positioning of YCbCr samples Figure 7.2-3 4:2:2 Co-Sited Sampling. The sampling positions for the 4:2:2 format. For every two horizontal Y samples, on the active scan lines of an interlaced picture. CHAPTER 7.2 Colour spaces SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE SAMPLE Y7 - 4 Y2 - 1 12 BITS 16 BITS SAMPLE CB7 0 CR7 0 CB7 2 CR7 2 CB7 4 CR7 4 SAMPLE CB7 0 CB5 0 CB3 0 CB1 0 CB7 4 CB5 4 CB6 0 CR6 0 CB6 2 CR6 2 CB6 4 CR6 4 CB6 0 CB4 0 CB2 0 CB0 0 CB6 4 CB4 4 CB5 0 CR5 0 CB5 2 CR5 2 CB5 4 CR5 4 CR7 0 CR5 0 CR3 0 CR1 0 CR7 4 CR5 4 CB4 0 CR4 0 CB4 2 CR4 2 CB4 4 CR4 4 CR6 0 CR4 0 CR2 0 CRO 0 CR6 4 CR4 4 CB3 0 CR3 0 CB3 2 CR3 2 CB3 4 CR3 4 CB2 0 CR2 0 CB2 2 CR2 2 CB2 4 CR2 4 0 = SAMPLE 0 DATA CB1 0 CR1 0 CB1 2 CR1 2 CB1 4 CR1 4 - 1 = SAMPLE 1 DATA CBO 0 CRO 0 CBO 2 CRO 2 CB0 4 CRO 4 -2 = SAMPLE 2 DATA 3 SAMPLE 3 DATA -