Slashdot Mirror

← Back to Stories (view on slashdot.org)

TiVo to support HDTV by "Year-End"

Posted by CmdrTaco on from the i'll-believe-it-when-i-see-it dept.

JMorgan in Seattle writes "TiVo has (finally!) announced support for HDTV. It's a ways off (end of the year), but at least we know that HD TiVo is on the horizon. In two separate press releases, we learn that TiVo will support both standalone and DirecTV hi-def PVRs. TiVo is really on a roll--first Rendezvous support, and now this. Now if only DirecTV would add more HDTV channels..." I've been waiting to get an HDTV receiver for this. Joy.

5 of 267 comments (clear)

  1. Re:Hmm by Tyler+Eaves · · Score: 5, Informative

    That's 2.5MB/sec.

    You'd need ~9GB per hour. So the largest harddrive available currently would give a whopping 20 hours of recording.

    --
    TODO: Something witty here...
  2. More announcements from the CES... by xTK-421x · · Score: 5, Informative

    Toshiba DVD-R + Tivo box

    Remote scheduling, intra-tivo video sharing, and MP3/JPG display on Series2 Boxes

    --
    "TK-421, why aren't you at your post?"
  3. Comment removed by account_deleted · · Score: 5, Informative

    Comment removed based on user account deletion

  4. Re:will require larger Hard Drives.... by Twirlip+of+the+Mists · · Score: 5, Informative

    Let me throw some facts into this mix. Your analysis is right on, but you need more info.

    Uncompressed HDTV requires about 1.3 Gbps of bandwidth to transmit. That's the SMPTE 292M standard for serial digital 4:2:2 YUV 1080i HD. Nobody outside of the TV studio ever sees uncompressed HD.

    When a network sends its broadcasts to an affiliate, it's not unusual for that signal to come down at about 45 Mbps over an OC-3. So the signal has already been compressed one time before it ever gets to your local TV station.

    The 8VSB transmission standard for broadcast HDTV calls for an effective bandwidth of about 19.3 Mbps between the TV transmitter and your house. So before the signal hits the airwaves, it gets compressed a second time.

    So the most your TiVo will ever need to store for over-the-air (OTA) HD is about 19.3 Mbps. That includes the 1080i signal and the Dolby Digital 5.1 audio.

    For satellites and (eventually) land-based cable, the facts are a little different, but the gist is the same. I believe DirecTV is currently broadcasting at about 15 Mbps on its various HD transponders.

    So all HDTV programming is compressed at least once and down to at least a ratio of about 70:1 before it ever gets to your house. This can be made to work for two reasons. First, your HDTV can't resolve all of the detail in an uncompressed HD frame. The set just isn't capable of it. Second, a good HD encoder can produce a 19 Mbps signal from a 1.3 Gbps signal that is free of visible artifacts. Note that I said a good encoder. Last week's broadcast of "Any Given Sunday" on ABC looked like hammered shit because it had been run through a poor encoder. Macroblocking everywhere. Virtually unwatchable.

    So let's say your TiVo stores the incoming signal without additional compression. OTA HD (19 Mbps) requires about 2.5 MB/s of storage space, or about 8.25 GB/h. So a TiVo with an 80 GB hard drive could store nearly 10 hours of HD content, and considerably more SD content. Given that 320 GB hard drives are available, it's easy to imagine a high-end or upgraded TiVo that has room for as much as 70 or 80 hours of HD content. Not half bad.

    So to sum up: "uncompressed" HD (meaning HD that is not compressed further once it gets to your house) requires slightly more than 8 GB per hour. Additional compression applied to the OTA or satellite signal is likely to result in very objectionable artifacts, unless TiVo spends a lot of money on their encoder hardware. Since people who buy HD equipment are currently on the high end of the market, it will make more sense for TiVo to spend the money on additional storage and simply omit an HD encoder from the device completely.

    A 10-hour TiVo (note that these are 19 Mbps HD numbers only; SD capacities will be four to six times higher) will require one 80 GB HD or two 40 GB HD's. The upgrade path could possibly include adding 80, 160, or 320 GB hard drives to get to a final capacity of up to 80 hours (rounded up) for a few hundred dollars over the base price. Not too bad.

    --

    I write in my journal
  5. Re:Now if they would only support broadband by entrager · · Score: 5, Informative

    TiVo is adding support for USB->ethernet connection in April this year. It will come with the new software that all Series2 TiVo users will get.

    That's when the OFFICIAL support comes out. Unofficially TiVo can use a USB->Ethernet adaptor now. You set your dialing prefix to ,#401 and it will use ethernet instead of the phone line. VERY nice.