x. Outputs of this process are the picture colPic, the co-located macroblock mbAddrCol, the motion vector mvCol, the reference index refIdxCol, and the variable vertMvScale (which can be One_To_One, Frm To Fld or Fld_To_Frm). When RefPicList1 [0] is a frame or a complementary field pair, let firstRefPicL1Top and firstRefPicL1Bottom be the top and bottom fields of RefPicList1[[0], respectively, and let the following variables be specified as topAbsDiffPOC = Abs( DiffPicOrderCnt( firstRefPicL1Top, CurrPic ) ) (8-175) bottomAbsDiffPOC = Abs( DiffPicOrderCnt( firstRefPicL1Bottom, CurrPic)) (8-176) Rec. ITU-T H.264 (01/2012) The variable colPic specifies the picture that contains the co-located macroblock as specified in Table 8-6. Table 8-6 - Specification of the variable colPic field_pic_flag RefPicList1[ 0 mb_field_decoding_flag additional condition colPic a field of a the frame containing decoded frame RefPicList1 0] a decoded field RefPicList1[ 0 a decoded frame RefPicList1[0] topAbsDiffPOC < firstRefPicL1Top bottomAbsDiffPOC topAbsDiffPOC >= complementary firstRefPicL1Bottom bottomAbsDiffPOC field pair (CurrMbAddr 1) ==0 firstRefPicL1Top (CurrMbAddr & 1) !=0 firstRefPicL1Bottom NOTE - The picture order count values of a complementary field pair marked as "used for long-term reference" have an impact on the decoding process when the current picture is a coded frame, the current macroblock is a frame macroblock, and the complementary field pair marked as "used for long-term reference" is the first picture in reference list Let PicCodingStruct( be a function with the argument X being either CurrPic or colPic. It is specified in Table 8-7. Table 8-7 - Specification of PicCodingStruct(X) X is coded with field_pic_flag equal to mb_adaptive_frame_field_fla PicCodingStruct( X) The variable luma4x4BlkIdx is derived as follows: If direct_8x8_inference_flag is equal to 0, luma4x4BlkIdx is set equal to (4 * mbPartIdx + subMbPartIdx). Otherwise (direct_8x8_inference_flag is equal to 1), luma4x4BlkIdx is set equal to (5 * mbP