Talk:Serial Digital Interface
From Wikipedia, the free encyclopedia
Digital Betacam has 20 bit audio. This article puts the bit depth of SDI embedded audio at 16 bit. Is SDI embedded audio 20 bit capable? I can't seem to find the answer.
All these names for the same thing are driving me nuts. Is this the same as CCIR 602 and D1 video?
[edit] Rewrite
I rewrote the article, including lots of additional information, and removing lots of factual errors. I also removed the cleanup tag. Hope you all like it. --EngineerScotty 08:36, 5 March 2006 (UTC)
SD-SDI can carry up to 16 channels of embedded audio. The sample rate will be 48 kHz and quantizing resolution of 20 and 24 bits are supported. HD-SDI is the same except that the audio channels are always carried at 24 bits. Of course not all of these bits are necessarily meaningful. The original capture of the material may be at resolutions as low as 16 bits. That will be as much information is trully present downstream, regardless of the bandwidth of the channel. Signals at different bitdepth are always carried such that the most significant bits are aligned with each other. In other words, higher bit depth will provide more granularity (and thus a lower noise floor), but does not make the signal louder. user: tvhead
[edit] Confusion over Colorimetry
There probabably needs to be a paragraph pointing out that the values of Y, Cb and Cr are different for HD (1080i and 720p), versus SD (576i and 480i) (also ED 576p and 480p), because of the differences between Recommendations 709 and 601.
Also there's a lot of computer editing and format conversion software that doesn't recognise the overshoot margins inbuilt into the digital gamut of the ITU-R/SMPTE standards.
