tra8x8PredMode luma8x8BlkIdx ] as the output. For each luma block of 8x8 samples indexed using luma8x8BlkIdx = 0..3, the following ordered steps are specified: 1. The Intra_8x8 sample prediction process in clause 8.3.2.2 is invoked with luma8x8BlkIdx and the array S'L containing constructed samples prior to the deblocking filter process from adjacent luma blocks as the input and the output are the Intra_8x8 luma prediction samples pred8x8L[ X, y ] with X, y = 0..7. The position of the upper-left sample of an 8x8 luma block with index luma8x8BlkIdx inside the current macroblock is derived by invoking the inverse 8x8 luma block scanning process in clause 6.4.5 with luma8x8BlkIdx as the input and the output being assigned to (xO, yO ). The values of the prediction samples predL_ xO + X, yO ] with X, y = 0..7 are derived by predL[xO+x,yO+y]=pred8x8L[x,y (8-71) 4. The transform coefficient decoding process and picture construction process prior to deblocking filter process in clause 8.5 is invoked with pred and luma8x8BlkIdx as the input and the constructed samples for the current 8x8 luma block S'L as the output. 8.3.2.1 Derivation process for Intra8x8PredMode Inputs to this process are the index of the 8x8 luma block luma8x8BlkIdx and variable arrays Intra4x4PredMode (if available) and Intra8x8PredMode (if available) that are previously (in decoding order) derived for adjacent macroblocks. Output of this process is the variable Intra8x8PredMode[luma8x8BlkIdx ]. Table 8-3 specifies the values for Intra8x8PredMode[luma8x8BlkIdx ] and the associated mnemonic names. Table 8-3 - Specification of Intra8x8PredMode[luma8x8BlkIdx ] and associated names Intra8x8PredMode| luma8x8BlkIdx Name of Intra8x8PredMode| luma8x8BlkIdx ] Intra_8x8_Vertical (prediction mode) Intra_8x8_Horizontal (prediction mode) Intra_8x8_DC (prediction mode) Intra_8x8_Diagonal_Down_Left (prediction mode) Intra_8x8_Diagonal_Down_Right (prediction mode) Intra_8x8_Vertical_Right (prediction mode) Intra_8x8_Horizontal_Down (prediction mode) Intra_8x8_Vertic