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TV "Broadcasting" Over Wireless Networks?

Posted by Cliff on from the lower-barriers-to-entry dept.

nuggetman asks: "This year we're starting an in-high-school TV network. What we would like to do is be able to broadcast from anywhere in the building using our wireless 802.11b network. In doing some tests at home, I discovered 802.11b has enough bandwidth to allow me to send live video at VHS quality (320x240 29.97fps) w/ FM quality audio when using Windows Media encoder on the sending end, and Windows Media Player at full screen on the receiving end. When applied in school, the receiving computer would simply output the full screen display to a TV signal. Are there any other free (as beer) solutions that would let us do this, other than WMP?"

14 of 66 comments (clear)

  1. several options... by Pathwalker · · Score: 4, Informative
    You have all sorts of options:
    • If you have access to a Mac, then QuickTime Broadcaster would be an excellent choice, as it supports broadcast and multicast, so you can have several machines playing the same stream without duplicating data.
    • If you have access to a Unix like system (Linux, OSX, FreeBSD, Solaris, Irix, HPUX, etc...) then mpeg4ip should let you do much of what QuickTime Broadcaster does, with a bit more hassle.
    Some other choices would be: and probably many more.
  2. Use Shoutcast! by TermAnnex · · Score: 5, Informative

    Nullsoft developed NSV, nullsoft streaming video.
    It can use a regular shoutcast server and winamp to play it.

    It's a bit poorly documented, but any geek should be able to figure it out. It can play a set of files in a loop, do live feeds, etc.

    http://www.nullsoft.com/nsv/

    1. Re:Use Shoutcast! by irc.goatse.cx+troll · · Score: 2, Insightful

      Too inefficient. Shoutcast is just mangled http -- Each client makes a new connection. For broadcasting you really need multicast (everyone gets the signal, but not everyone is 'listening')

      --
      Pain lasts, kid. Its how you know you're alive. Sometimes I think this growing up thing is just pain management-TheMaxx
  3. This is not VHS quality by HotNeedleOfInquiry · · Score: 3, Interesting
    live video at VHS quality (320x240 29.97fps)

    Sorry, the best you can say is near VHS quality. And I don't even agree with that. A fresh, first generation tape in a good machine blows 320x240 away any day.

    Tell the truth and people will trust you.

    --
    "Eve of Destruction", it's not just for old hippies anymore...
    1. Re:This is not VHS quality by RzUpAnmsCwrds · · Score: 4, Insightful

      "A fresh, first generation tape in a good machine blows 320x240 away any day."

      Yeah, and a 128kbit MP3 may not hold a candle to a fresh, properly mastered CD. But most CDs aren't properly mastered: they have their dynamic range compressed so much that they are clipping almost constantly. When most people think of VHS, they think of their own personal recordings or old tapes from Blockbuster, not the full capability of the medium.

  4. But... Beer isn't free? by jerde · · Score: 2, Funny

    Are there any other free (as beer) solutions?

    This is a stupid question: where on earth did that phrase come from? Beer isn't free, is it? Have I been ripped off all along?

    Is there a /. culture FAQ out there somewhere that documents this, the "in Soviet Russia [object] [verb] [subject]" thing, and the "1. xxx, 2. ?, 3. Profit!" spiel?

    - Peter

    --
    INsigNIFICANT
    1. Re:But... Beer isn't free? by glivings · · Score: 2, Informative

      Is there a /. culture FAQ out there somewhere that documents this, the "in Soviet Russia [object] [verb] [subject]" thing, and the "1. xxx, 2. ?, 3. Profit!" spiel?
      1. in soviet Russia.... a tired Yakov Smirnov bit.
      2. the "step 1: xxx, 2: ? 3: Profit!" spiel is from the underpants gnomes episode of South Park. In the episode, the underpants gnomes explain their business model:
      Step 1: Collect underpants
      Step 2:
      Step 3: Profit!

    2. Re:But... Beer isn't free? by nuggetman · · Score: 2

      This is a stupid question: where on earth did that phrase come from? Beer isn't free, is it? Have I been ripped off all along?

      It's simply a way to differentiate the types of free.

      If something is free (as in beer), it's free in the sense you don't have to pay for it, but you don't have direct access to the recipie so to speek.

      If it's free (as in speech), it's related to liberties.

      --
      ...and that's all there is to it.
  5. Try a real TV transmitter by SchnauzerGuy · · Score: 3, Informative

    You'll probably find that, even with light traffic, 802.11b is going to be too slow and unrealiable for 30fps streaming video...

    Since you are going to output to a TV anyway, why bother with computers/802.11b and broadcast directly using a small TV transmitter. I would have expected Ramsey to have a transmitter kit, but all they seem to have these days is a semi-cheesey 'cube' transmitter. Even so, the high powered version might be good enough for what you are looking for, especially with a good antenna.

    A quick Google search turned up some other kits. Most of these have a fairly short range, but with good antennas, they'll easily transmit further (and with higher quality), than compressed video over 802.11b. Plus, if you get a kit, building it can be a nice little project for an electronically minded student.

    1. Re:Try a real TV transmitter by Zarf · · Score: 2, Informative

      Out of all the suggestions on this page, I like this(See the bottom of the page) idea the best. The reason I like SchauzerGuy's solution best, is because it's actually TV. That means that All those school TV's can just tune to the right channel... no 802.11b muss and fuss. That means the solution can leverage the existing infrastructure of the school giving it larger effective coverage.

      I know it's not free as in beer but it's definately the best solution for the ultimate application. Thirty-five bucks isn't bad though.

      And think, nuggetman, you do this and you'll be the demi-god who brought your school it's own TV station. Woof! Later projects could incorporate sending that signal to a website or what not... encoding the school TV programs as movies that could be accessed via a web page. A webpage on the school's internal network maybe.

      I like it because it's simple. It's simple because it's just TV.

      --
      [signature]
  6. What's limiting you? by Wonko42 · · Score: 3, Interesting
    It's 802.11b, so at best you've got 11Mbps to play with, and at worst 1Mbps. Why limit yourself to crappy 320x240 "VHS-quality" video? Windows Media is a good solution, I agree, but you could probably get away with 480x360 encoded at 768Kbps, plus a 128Kbps audio stream for a total of 896Kbps, which still puts you under the minimum 1Mbps speed of your 802.11b network and gets you much more bang for your buck. Of course, I'm not accounting for TCP overhead, but I know I can stream 1600Mbps DivX video from the 802.11b base station in my bedroom to the QCast in my living room without any problems.

    In any case, bandwidth considerations aside, if you want a WMP alternative, try Nullsoft Streaming Video and Winamp 2.9x (as a few other commenters have suggested). It's good stuff.

    1. Re:What's limiting you? by Anonymous Coward · · Score: 2, Informative

      Incorrect. You do not get 11Mbps. You get 5.5... full duplex. Or so. You end up with at most about 4Mbits of usable bandwidth with 802.11b in my experience.

  7. Oh man WMP streaming... by curious.corn · · Score: 2, Insightful

    ... goto videolan.org and enjoy. I've streamed a divx @ 150Kb/s by just pointing to an http location; you on the other hand can't do that or you won't be able to stream more than 2~3 clients. You want broadcast and videolan does just that! Check the link ASAP, it was designed for you.

    --
    Mi domando chi à il mandante di tutte le cazzate che faccio - Altan
  8. Let's pretend you have linux... by Zarf · · Score: 2, Informative

    just because I like linux so much I'll pretend that you have linux...

    Check out: http://www.videolan.org/


    The player works on lots of platforms including windows but the server has to be linux. Now that's fine with me. I'm wondering about Digital Video and digital editing too...
    You may also look at these links:
    http://cs.uhh.hawaii.edu/~jeschke/links/video.html
    This fella has made a pretty good collection of links that he's researched. Hey, I'm interested in this idea now... I think I may have an idea for a project.

    --
    [signature]