Hardware architecture design for H.264/AVC intra frame coder

In this paper, we contributed a VLSI architecture design for H.264/AVC intra frame coder. First, analysis of coding algorithm is provided by using a RISC model to obtain the proper degrees of parallelism under SDTV specification. Second, a two-stage macroblock pipelining is proposed to double the processing capability and hardware utilization. Third, Hadamard-based mode decision is modified as DCT-based version to reduce the 40% of memory access. To sum up, our system architecture achieves 215 times of speed compared with RISC-based software implementation in terms of processing cycles. In addition, we also made a lot of efforts on developing area-speed efficient modules. Reconfigurable intra predictor generator can support all kinds of prediction modes. Parallel multi-transform has four times throughput of the serial one with little area overhead. CAVLC engine can efficiently provide coding information for the bitstream packer. A prototype chip was fabricated with TSMC 0.25 μm CMOS technology and is capable of encoding 720×480 4:2:0 30 Hz video in real time at the working frequency of 54 MHz. The transistor count is 429 K, and the core size is only 1.855×1.885 mm².