November 22, 2007

  • a good article

    http://forum.ecoustics.com/bbs/messages/34579/122868.html

    Sometimes when reading the reviews on amazon.com, I find it funny how people assume that because a signal is digital, it is somehow magically "perfect."  Digital signals are of course subject to degredation just as analog signals are.  Most digital signal systems have both very strict cable requirements and length limitations (eg the familiar cat5 ethernet for 100mbit - up to 100m, cat 5e for 1000 mbit up to 100m, single mode fiber for long distance fiber optics, etc etc), and they also tend to have error correction built in - implying there is the chance of some errors in the signal.  It's interesting when designing HDMI they chose to put no error correction into it.  But maybe that's because (as that article says) HDMI is just exactly DVI with some extra stuff (eg audio).  And it's a lot more reasonable to think they didn't put error correction into DVI.