DNxHD codec
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Avid DNxHD is a high-definition video post-production codec engineered for multi-generation compositing with reduced storage and bandwidth requirements. It was developed by Avid Technology, Inc.
Uncompressed high definition digital video is substantially more data than standard definition and can overwhelm general-purpose computer systems. Other codecs such as HDV, DVCPRO HD, and HDCAM use compression techniques that limit the spatial and temporal resolution of the image. While suitable for acquisition, these codecs will tend to degrade the image over the multiple encode-decode cycles that are typically required during the post-production of complex layered imagery.
DNxHD offers a choice of 8- or 10-bit depth at three user-selectable bit rates. DNxHD essence is typically stored in an MXF wrapper (Op-atom format), although it can also be stored in Quicktime or AVI wrappers.
DNxHD is intended as an open standard. Ikegami's Editcam camera system for example records directly into DNxHD encoding. Such material is immediately accessible by editing platforms that support the DNxHD codec. The source code for the Avid DNxHD codec is licensable free of charge.
In the Avid family of editing products, Media Composer systems and lower are limited to using DNxHD compression. These systems do not feature uncompressed HD editing (although many do support uncompressed editing at SD resolution).