Variable block size transforms with higher order kernels for ultra-high definition video coding

In this paper, 16-order and 32-order integer transform kernels are designed for the HD video coding in H.264|MPEG-4 AVC and the performance analyses for large transforms are presented. An adaptive block size transform coding scheme is also proposed based on the proposed transform kernels. Thus, additional 16-order (16 × 16, 16 × 8 and 8×16) and 32-order (32×32, 32×16 and 16×32) transforms are performed in addition to 8×8 and 4×4 transforms which are exploited in the Fidelity Range Extension of H.264|MPEG-4 AVC. The experimental results show that the variable block size transforms with the proposed higher order transform kernels yields 14.96% of bit saving in maximum for HD video sequences.