A method and apparatus of depth coding using depth modelling mode 1 (DMM1) are disclosed to reduce the wedgelet pattern table size. In one embodiment, a size-reduced wedgelet pattern for a reduced wedgelet pattern table is generated by excluding at least one non-corner adjacent-edge sample for adjacent-edge partition or at least one opposite-edge sample for opposite-edge partition from starting positions or from ending positions. The reduced wedgelet pattern table may also include at least one omitted wedgelet pattern in at least one wedgelet direction category. For the adjacent-edge partition, the starting positions and the ending positions may correspond to every other even non-corner adjacent-edge samples in a first and a second adjacent edges respectively. For the opposite-edge partition, the starting positions correspond to every other even opposite-edge samples in a first opposite edge and the ending positions include all opposite-edge samples in a second opposite edge.