DNxHD
Also known as: DNxHR, Avid DNx
Avid's intermediate codec family, the alternative to ProRes for editing, designed to be decoded quickly rather than compressed hard.
Updated
What it means
An intermediate codec trades size for ease. DNxHD files are much larger than camera files and far quicker for a machine to decode, which is the whole point of the format. Nothing about the format is intended for delivery to a viewer.
It is the Avid counterpart to ProRes. The two solve the same problem from different directions, and most applications now read and write both of them without comment.
DNxHR is the later variant. It removed the fixed-resolution restriction, so the same codec covers 4K and above where DNxHD was built around HD and nothing above it.
How it works in practice
It is what a long edit runs on comfortably. Converting camera files to an intermediate before editing removes the decoding load that makes a timeline stutter. Disk space is what pays for that convenience.
Proxies are the lighter version of the same idea. ProRes Proxy or a low DNx tier gives a responsive timeline, and the originals come back for the final Rendering and export at full quality.
Tier choice is the only real decision. The higher tiers are near-lossless and large; the lower ones are visually fine for an edit and much smaller on disk for the same timeline.
What to watch out for
It is not a delivery format. A DNx file sent to somebody expecting to watch it is enormous and probably unplayable, which is a Codec support misunderstanding rather than a fault in the file.
Storage goes quickly. An hour of intermediate footage can occupy several times what the camera files did, and Gigabytes per hour at these rates surprises people exactly once.
Converting unnecessarily wastes an evening. Modern machines handle camera codecs directly for short edits, so the step is worth taking for a long timeline and and not for a short session edit.
How RawClip handles it
Camera files are read directly rather than converted to an intermediate first, since the analysis does not need a scrubbable timeline. Intermediate files upload and work normally in cases where somebody already has them, at the expense of a considerably longer upload.