DNxHD: Difference between revisions

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* FourCC: ?
* FourCC: AVdn ([[QuickTime]])
* Company: [[AVID]]
* Company: [[AVID (Company)|AVID]]


This codec is very similar to [[JPEG]]. Every frame is independent and consists of VLC-coded DCT coefficients.
This codec is very similar to [[JPEG]]. Every frame is independent and consists of [[VLC|VLC-coded]] [[DCT]] coefficients.


Header consists of many parts and may include quantization tables and 2048 bits of user data. Also each frame has two GUIDs and timestamp. All header is packed into big-endian dwords.
Header consists of many parts and may include quantization tables and 2048 bits of user data. Also each frame has two GUIDs and timestamp. The frame header is packed into big-endian dwords.


Actual frame data consists of packed macroblocks with technique almost identical to JPEG: DC prediction and variable-length codes with run length encoding for other 63 coefficients.
Actual frame data consists of packed macroblocks with technique almost identical to JPEG: DC prediction and variable-length codes with run length encoding for other 63 coefficients.
DC coefficient is not quantized.
Can be wrapped in [[MXF]] and [[MOV]].
[[SMPTE]] standardized it as VC3.
FFmpeg decoder: [http://svn.mplayerhq.hu/*checkout*/ffmpeg/trunk/libavcodec/dnxhddec.c?content-type=text%2Fplain dnxhddec.c]
FFmpeg encoder: [http://svn.mplayerhq.hu/*checkout*/ffmpeg/trunk/libavcodec/dnxhdenc.c?content-type=text%2Fplain dnxhdenc.c]
SMPTE spec:
http://www.atwork.loyalistc.on.ca/heidendahl/SMPTE/SMPTE%20Standards/S2019-1-2008.pdf (requires login)
[[Category:Video Codecs]]
[[Category:Video Codecs]]

Latest revision as of 16:08, 2 February 2012

This codec is very similar to JPEG. Every frame is independent and consists of VLC-coded DCT coefficients.

Header consists of many parts and may include quantization tables and 2048 bits of user data. Also each frame has two GUIDs and timestamp. The frame header is packed into big-endian dwords.

Actual frame data consists of packed macroblocks with technique almost identical to JPEG: DC prediction and variable-length codes with run length encoding for other 63 coefficients.

DC coefficient is not quantized.

Can be wrapped in MXF and MOV.

SMPTE standardized it as VC3.

FFmpeg decoder: dnxhddec.c

FFmpeg encoder: dnxhdenc.c

SMPTE spec:

http://www.atwork.loyalistc.on.ca/heidendahl/SMPTE/SMPTE%20Standards/S2019-1-2008.pdf (requires login)