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What's the Matter with HDMI?

mrnomas writes with a link to the Audioholics site, which wonders why the HDMI standard is such a mess? The article's author suggests that the format was designed for the benefit of the content-producers and not the consumer. The result is a signal that's hard to route and switch, as well and unnecessarily complicated cable assemblies. They reach back to the DVI standard to see what might be done to make HDMI a little more consumer-friendly, with numerous technical elements woven through the discussion. "DVI lacked a couple of things which the consumer audio/video industry wanted. It was implemented on a variety of HD displays and source devices, but it was confusing for the consumer because of the many variants on the standard and different connector configurations, and it didn't carry audio signals. A consortium to develop and promote a new interface, HDMI, was formed; the idea was to come up with a standard which could be implemented more uniformly, was less confusing, and offered the option of routing audio signals along with video."

11 of 390 comments (clear)

  1. As a manufacturer of Video Distribution by JohnnyComeLately · · Score: 4, Interesting

    We commonly get asked, "Whats the difference between HDMI and Component?". Our answer (tongue in cheek) is, "About $20 a foot". I bought a 1080i LCD Sony Bravia HDTV and I got a DVD at the same level. When I got to interconnect cables, I saw $30 for a reasonable set of Monster component cables. The no-brand HDMI 3 foot cable was $90. It's silly if you think about it. OK, supposedly there's a sync difference and the "transmission is faster" for HDMI, but last I checked, component video hasn't had a lag problem in anyone's home theater I've seen. You can send 1080p just fine over component, and not be worried about anything holding your performance back. This is why I laughed at the XBOX360 HDMI only output....please...when will manufacturers figure out that when you limit choices it just pisses people off?

    1. Re:As a manufacturer of Video Distribution by Anonymous Coward · · Score: 1, Interesting

      I thought that in anticipation of HDCP and company, most DVD players will not upconvert to 720/1080 on the component outputs. Do non blu-ray/HD-DVD DVD players output 720/1080 on anything other than HDMI/DVI?

    2. Re:As a manufacturer of Video Distribution by networkBoy · · Score: 2, Interesting

      Not entirely true.
      While I agree digital is digital, and as such analog artifacts are largely ignored, there is a specific issue with HDMI, namely inter-lane skew.

      DVI/HDMI video is three data pairs on a 100ohm differential line and one differential clock.
      If the analog artifacts (specifically capacitance and uneven cable lengths) are bad enough the "eye" of the differential signal may close to the extent that the op-amp at the receiver may not be able to sense and output a clean signal. Further damage to the signal is caused by inter lane skew, where the clock edges are not in sync with the data edges. These are analog effects that will impact overall picture quality. Also, effects like these are heavily exacerbated by length of the cable.

      Mind, I'm not claiming that the monster brand is any better than generic (they are all made in about 5 factories in china), just that cable really still matters, even though the signal is digital. What I would like to see is XAUI or Fiber for video.
      A single singlemode strand of fiber would be cleaner and vastly less mechanical load on the connector, and would have enough bandwidth for about 3 1080p streams. A multimode fiber would handle 720P (and likely 1080p but I need to do some math) and is vastly more resistant to dust.
      -nB

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  2. The problem is... by Cadallin · · Score: 3, Interesting
    HDMI was not designed as a solution to an engineering problem. It was designed as an anti-consumer technology in the first place. Which is the entire problem. HDMI was designed from the ground up to be a DRM crippled interconnect. This gives rise to a number of paradoxes about the connection.

    Why would you want audio and video in the same cable? Especially for expensive systems where HDMI is common now. Is anyone with a >$1000 display actually using built-in speakers? If so, what's wrong with you? Go get some decent speakers.

  3. Re:what might be done? by UserChrisCanter4 · · Score: 2, Interesting

    And that pretty much sums it up. Other than the DRM issues, HDMI is a solid interface (which is, of course, like the old joke about "other than that, how was the play Mrs. Lincoln?").

    A combination of DVI plus audio was pretty much a foregone conclusion. DVI had taken over the computer world in the monitor interface department, and it's competitors are fewer and fewer these days. Allowing for easier connection of computers and computer-like media devices was becoming more and more important, and DVI was there and ready. The myriad of pins on the DVI connection make for a chunky connection, which is a bigger problem on TV gear than on a computer, so a shrinking of the interface is logical.

    Other than a more secure attachment method (latch? Thumbscrews?), HDMI is a decent interface: 1080p (and beyond) capable, 48-bit color in the latest version, and enough bandwidth for the newer audio signals. Sure, there are problems past 50 or 60 ft. runs, but those honestly comprise such a tiny amount of installs that it shouldn't be a primary concern for any consumer video interface. 50 Ft. is more than enough for a pretty nice projector install; if you need more than that, cost likely isn't a huge factor and an inline repeater shouldn't be a big deal.

    No, it's the DRM that causes issues with the handshake when switching signals. It's the DRM that will make us eventually change out a perfectly good videocard if we want the Hi-Def formats. It's the DRM that complicates what would be simple external switch boxes. It would have been nice to see HDMI evolve along with component as the high-end, easier hook-up alternative, but instead component is being dropped because of the "analog hole" problem that makes all but the industry big wigs laugh.

    No, the cat's out of the bag - HDMI is here to stay, and other than the current DRM issues, it's a pretty decent interface. My wish for the future would be something similar to what firewire was supposed to be: every box with an "in" and an "out" interface, strung along in a SCSI-like chain from A to B to C to TV. Or some miracle 10gbps wireless that's reliable enough for this type of situation. Here's hoping.

  4. DRM? Did anyone even RTFA? by brunes69 · · Score: 1, Interesting

    The whole article is about twisted pair vs. coax and why HDMI sucks for long cable runs. it has NEXT TO NOTHING to do with DRM.

    Aside from that - this article is pointless. HDMI is not DESIGNED for long runs. Its to go from your TV to your reciever, that's it. No one transmits video over long runs anymore - the type of crap he talks about in the article (running video to a set 300 feet away) seems so 10 years ago - nowadays everyone who wants to do this kind of thing has a central media server serving the CONTENT to their set-top device to play it - no one streams video all over the freaking place.

    If it were up to this guy HDMI cables would cost about $100 for a 3 foot cable instead of being able to find them the $6 bin at your nearest big box.

    What a waste of time. Good thing no one in here RTFA but me anyways.

  5. Re:HDMI by Anonymous Coward · · Score: 1, Interesting

    One of the reasons Firewire was included on HDTVs was to standardize and simplify remote control operations in addition to receiving MPEG2 data. The idea was the TV remote would be able to change the channel on the cable/satellite box and adjust the volume on the receiver. There was hierarchy to connecting the devices together to accommodate high bandwidth usage.

  6. Re:more consumer-friendly? by Opportunist · · Score: 2, Interesting

    Linux Distributions? They got more and more consumer friendly with every incarnation. When I think back to the mid-90s distris...

    --
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  7. Re:HDMI by vbwilliams · · Score: 3, Interesting

    Less cables. Duh. Why would you want MORE/BIGGER cabling when you can funnel the stuff through the same media and just be done with it? Aside from the DRM concerns, I actually LIKE HDMI...it's just much easier to deal with. Likewise, finding receivers now with enough HDMI inputs vs component inputs is just a hell of a lot easier, just because of space alone. If it weren't for my Playstation 2 at this point requiring component or composite instead of HDMI, my system would be 100% HDMI, and I'd have a bit less cable management to do.

    My system:

    Receiver --> TV via HDMI
    HD Cable Box --> receiver via HDMI
    DVD --> receiver via HDMI
    HD-DVD --> receiver via HDMI
    Playstation 2 --> receiver via component video, optical audio

    Using 100% HDMI, I'd have a system with at least 2 less cables, and those cables would be pretty small in circumference as well. They'd be easier to manage. You simply mute the TV, and just control the audio from the receiver...only way you're going to get 5.1 digital anyway.

    Personally, I think HDMI is better than any other option currently available. The DRM is one thing. But outside of that, there's nothing else really to bitch about. And if you do your homework, you can find great HDMI cables for half the price of component video or optical audio.

  8. Re:The DRMintaor. by Anonymous Coward · · Score: 1, Interesting

    I'm sure there are plenty of mistakes that were made when designing HDMI. However, there's low adoption rate because there's a small number of HDTVs, the consumers aren't educated, and the cables are extremely costly. I think that might be the problem more than the fact that HDMI is made of twisted-pair cables. I'd say the low adoption rate is because the customers (not "consumers") *are* educated. Cost? See other posts in this thread, not an issue -- some people are getting them for like $3 or less. But, the real problems with HDMI are a) reliability b) rights restrictions. Oh and c) the "good enough" factor.

              Reliability -- they talk about this in the article, mentioning quite simply that the signalling and cabling system used is not that robust; future revisions (HDMI 1.3) are less robust, simpling running higher data rates over the same cable.

              Rights restrictions. HDMI is really just DVI with audio built in, with rights restrictions slapped on. Plenty of people do decide just not to bother when they hear how much trouble the industry has gone to to try to restrict how they can use their own equipment. And it REALLY doesn't make people want to get HDMI when they hear about the combination of these two problems -- the cases where HDMI is unreliable *because* of malfunctions in the rights restriction system it uses.

              "Good enough". This really is why many people haven't gotten HDTVs to begin with.. I don't have a TV because I use mythtv, and I have no interest in watching my shows in high def. A lot of people with TVs have no interest either. And for people that DO have high def and already use component cabling, plenty will keep it.
  9. Re:The DRMintaor. by UncleTogie · · Score: 3, Interesting

    You probably lose a few pixels every billion, not really a big deal.
    Believe it or not, I'm NOT looking forward to the all-digital cable switch in 2009. This hit home two nights ago, as we were watching Futurama. I was watching on my PC {analog} while my fiance and roommate were watching using the digital set-top box. We'd had some rain recently, and the set-top kept dropping seconds of video at a time. The analog connection had just a BIT of fuzz, but not enough to lose captioning [usually the first victim of low signal strength.]

    I'll take robust over bandwidth.
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