al_Left (prediction mode) Intra_8x8_Horizontal_Up( (prediction mode) Intra8x8PredMode| luma8x8BlkIdx ] is derived as specified by the following ordered steps: 1. The process specified in clause 6.4.11.2 is invoked with luma8x8BlkIdx given as input and the output is assigned to mbAddrA, luma8x8BlkIdxA, mbAddrB, and luma8x8BlkIdxB. 2. The variable dcPredModePredictedFlag is derived as follows: If any of the following conditions are true, dcPredModePredictedFlag is set equal to 1: Rec. ITU-T H.264 (01/2012) the macroblock with address mbAddrA is not available, the macroblock with address mbAddrB is not available, the macroblock with address mbAddrA is available and coded in an Inter macroblock prediction mode and constrained_intra_pred_flagi is equal to 1, the macroblock with address mbAddrB is available and coded in an Inter macroblock prediction mode and constrained_intra_pred_flagi is equal to 1. Otherwise, dcPredModePredictedFlag is set equal to 0. For N being either replaced by A or B, the variables intraMxMPredModeN are derived as follows: If dcPredModePredictedFlag is equal to 1 or the macroblock with address mbAddrN is not coded in Intra_4x4 or Intra_8x8 macroblock prediction mode, intraMxMPredModeN is set equal to 2 (Intra_8x8_DC prediction mode). Otherwise (dcPredModePredictedFlag is equal to 0 and (the macroblock with address mbAddrN is coded in Intra 4x4 macroblock prediction mode or the macroblock with address mbAddrN is coded in Intra_8x8 macroblock prediction mode)), the following applies: If the macroblock with address mbAddrN is coded in Intra 8x8 macroblock prediction mode, intraMxMPredModeN is set equal to Intra8x8PredMode[ luma8x8BlkIdxN ], where Intra8x8PredMode is the variable array assigned to the macroblock mbAddrN. Otherwise (the macroblock with address mbAddrN is coded in Intra_4x4 macroblock prediction mode), intraMxMPredModeN is derived by the following procedure, where Intra4x4PredMode is the variable array assigned to the macroblock mbAddrN. intraMxMPredModeN = Intra4x4PredMode[luma8x8B