The Scalable Video Technology AV1 (SVT-AV1) encoder is an open-source software AV1 encoder that is architected to yield excellent quality-speed-latency tradeoffs on CPU platforms for a wide range of video coding applications. The SVTAV1 encoder is based on the SVT architecture, which supports multi-dimensional parallelism, multi-pass partitioning decision, multi-stage/multi-class mode decision, and multi-level spatiotemporal prediction and residual coding algorithms. Given a latency constraint, the SVT-AV1 encoder maximizes the CPU utilization on multicore CPUs, through picturebased parallelism for high-latency video applications, and through segment-based parallelism for low-latency video applications. The picture-level/segment-level parallelism allows the SVT-AV1 encoder to produce identical bit streams, irrespective of whether single- or multi-threaded encoding is performed. In mode decision, the SVT-AV1 encoder yields many speed-quality tradeoffs with high granularity, mainly through multi-pass processing of each superblock and multistage/ multi-class processing of each block, and through the different levels of the prediction/coding features. The resulting speed-quality tradeoffs of SVT-AV1 are compared, in Video-On-Demand (VOD) use-cases, to those of libaom (another open-source AV1 encoder), and to those of the latest x264 (AVC), x265 (HEVC) and libvpx (VP9) open source encoders.
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