A High Compression Efficiency Hardware Encoder for Intra and Inter Coding With 4K@30fps Throughput

The promotion of the HEVC standard has significantly alleviated the burden of network transmission and video storage. However, its inherent complexity and data dependencies pose a significant challenge in achieving high compression efficiency hardware encoder. To tackle this challenge, we propose several hardware-oriented algorithms and achieve a hardware encoder supporting both intra and inter coding. In terms of algorithms, our optimizations focus on intra mode decision, motion estimation (ME), rate estimation, and merge mode estimation. These optimizations reduce the computational complexity and address the data dependencies within and between encoder modules while maintaining an acceptable compression efficiency. As for hardware, we propose an encoder architecture that supports not only 35 intra prediction modes but also ME with an extensive search range of [±64, ±64]. The uniform $4\times 4$ engine, 2-D data reuse, and timing schedule for intra and inter coding are presented in this architecture to optimize the hardware resource consumption and throughput. Compared with HM 15.0, the proposed hardware-oriented algorithms lead to a 1.88% and 14.57% increase in BD-Rate under the configurations of all intra and low delay P, respectively. Notably, the BD-Rate outperforms all existing hardware encoders supporting 4K resolution. In a GF 28nm fabrication process, the hardware design achieves a clock frequency of 550MHz, supporting 4K@30fps throughput with a hardware gate count of 3154K and memory usage of 1.02MB, and the proposed architecture demonstrates substantial advantages in terms of area, throughput, and power compared to other studies.