Development of Full-Featured 8K Recorder

Abstract

NHK has been researching a full-featured 8K ultrahigh-definition television system with a high frame rate of 120 Hz (8K/120 Hz) for future broadcasting. We have developed 8K encoder and decoder boards that support a popular video codec widely used in nonlinear editing (NLE). Installing these boards into our prototype 8K recorder realizes realtime 8K/120 Hz compression and decompression. The recorder can store 60 min of a compressed stream in a single removable memory with solid-state drives. We constructed an 8K post-production system and performed an 8K/120 Hz editing experiment with the recorded content. In the system, an NLE machine was connected to Redundant Arrays of Inexpensive Disks (RAID) devices through a high-speed interface appropriate for transferring a compressed 8K/120 Hz source. Common NLE software was used that works with 4K/60 Hz video reproduced from original 8K files by applying the resolution scalable decoding function of the codec, and the edited scenes were finally rendered at 8K/120 Hz system. With the 8K/120 Hz NLE system, approximately 350 min of footage was handled, and more than 100 min of content was mastered. To perform an 8K full-frame preview at editing sites, we also developed a peripheral playout module that incorporates a decoder for the recording codec and 8K/60 Hz output interface (quad-link 12G-SDI) in a single Peripheral Component Interconnect express (PCIe) card. By driving two modules in parallel, we achieved realtime 8K/120 Hz playout in a workstation. Furthermore, a compact removable memory with a nonvolatile memory express interface for offering good connectivity with editing systems was prototyped. These achievements can provide cost-efficient editing and playout, which makes 8K/120 Hz post-production more convenient than ever before.