Talk:DNxHD codec

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The second paragraph reads like an advert, and contains some irrelevant information;


"Uncompressed high definition digital video is substantially more data than standard definition and can overwhelm general-purpose computer systems."

Debateable... but is that relevant to the article anyway? I think this should go.

Remark SM: I am unknown to this all, and for a layman this information is usefull. The same goes for why in post-production you would want to use another codec than in the production it self. In short, the context helps newbies to understand it better. —Preceding unsigned comment added by 146.50.204.20 (talk) 11:07, 20 March 2009 (UTC)


"Other codecs such as HDV, DVCPRO HD, AVC-Intra, AVCHD, and HDCAM use compression techniques that limit the spatial and temporal resolution of the image."

I think the points that are trying to be made here are that;

  • DNxHD does not re-size the video; probably a good thing. DVCPROHD and AVC-Intra 50 class both re-size the video... they are lower bitrate, so presumably a trade-off is made between blur & DCT quantization type compression artifacts. DNxHD is probably high enough a bit rate not to benefit from sizing.
  • DNxHD is an intra compression format - i.e. it does not use motion-vector interpolated frames (B,P). This is probably a good thing given the intended market. HDCAM and HDV do use motion-vector interpolation - they are camera / VTR formats. HDCAM SR (much higher bitrate than DNxHD), DVCPROHD, and AVC-Intra do not. AVCHD is a consumer compression standard, and probably not relevant?

"DNxHD is an Intra compression format which does not resample the video" Would give the information, but with no context, and no reason. It doesn't explain very much. I don't know how to re-word this bit.


"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."

All the codecs named, including DNxHD will degrade the image over multiple encode-decode cycles. Intra codecs such as DNxHD etc (see above) will only degrade the frame being modified, which is a good thing. Assuming the previous point on the Intra nature of DNxHD were re-written successfully, I think this should go.

--Guiddruid (talk) 12:41, 18 February 2008 (UTC)

I don't believe HDCAM uses motion vectors; it is an I-frame only codec. C.anguschandler (talk) 09:52, 2 March 2009 (UTC)

I added an external link to a hardware codec chip for DNxHD -- the chip is unique and not easy to find and many readers will reasonably assume that there is no available chip for such a niche codec format, thus it can be a valuable info for wikipedia readers looking for real-time DNxHD HW for embedded video systems. I realize that it can by categorized as a 'promotional' link, but there is a MainConcept product link and Ikegami product link as well, so all product links should be deleted, or the Nethra codec chip link should be allowed. —Preceding unsigned comment added by Quattroluvr (talkcontribs) 17:03, 2 August 2010 (UTC)