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Television Media Wireless Networking Hardware

TV "Broadcasting" Over Wireless Networks? 66

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?"
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TV "Broadcasting" Over Wireless Networks?

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  • several options... (Score:5, Informative)

    by Pathwalker ( 103 ) * <hotgrits@yourpants.net> on Wednesday September 03, 2003 @11:32PM (#6866060) Homepage Journal
    You have all sorts of options:
    • If you have access to a Mac, then QuickTime Broadcaster [apple.com] 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 [mpeg4ip.net] should let you do much of what QuickTime Broadcaster does, with a bit more hassle.
    Some other choices would be:
    • Live Channel [channelstorm.com]
    • Sorenson Broadcaster
    • Real Encoder
    and probably many more.
  • http://www.apple.com/quicktime/products/broadcaste r/

    Buy a cheap iMac DV for like $300, and run Quicktime Broadcaster (it's free, as in beer).

    Good luck.
    • I'll agree, I've used QTBroadcaster and QTSS (actually Darwin Streaming Server, QTSS is MacOS X Server-only but they are essentially identical) and the results are excellent even using a low end iMac. I used it to stream my DirecTV signal to computers elsewhere in the house. I have an RF remote for the DirecTV so I could change channels from anywhere in the house.
      Note that Darwin Streaming Server runs on various platforms, including Darwin OS and Linux.
  • Quicktime Products [apple.com]

    Darwin Server works on anything....

  • Use Shoutcast! (Score:5, Informative)

    by TermAnnex ( 154514 ) on Wednesday September 03, 2003 @11:41PM (#6866096)
    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/
    • 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')

      • I don't think the intent is to send streaming video over 802.11 to every PC on the network. The intent is to send it to one PC in the CATV MDF, then modulate the RGBHV/Composite signal from the video card onto the CATV distribution system.
  • by HotNeedleOfInquiry ( 598897 ) on Thursday September 04, 2003 @12:10AM (#6866181)
    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.

    • "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. "

      Actually if you run 320 by 240 video, even compressed, to a TV it is hard to tell the difference. I used to have a setup like this at home.
    • by RzUpAnmsCwrds ( 262647 ) on Thursday September 04, 2003 @01:26AM (#6866435)
      "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.
    • Most tv's(especially ones that are a few years old) blur stuff together so much that I seriously doubt you can tell a difference. Then you through in the cheap tv out that'll be on any consumer grade video card at all and the difference will be even less. A few years ago I had the game Janes ATF where the videos were played back at 640x480 skipping every other vertical line, hooked up to a 27" tv it was impossible to tell. If your comparing it to a video being played back on your monitor thats a world of
  • by jerde ( 23294 ) on Thursday September 04, 2003 @12:35AM (#6866237) Journal
    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
    • 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?


      I was at a German block party a couple of weeks ago for "ascention sunday" or something. The beer was free as in beer there. It cost nothing, the semmel were three euro each, the steaks were three euro, but the beer was null euro... So I guess in Germany the Beer really is Free. But, you had to bring your own mug.
    • 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!
    • And, as for the "free(as beer)" concept, it boils down to the two types of free:

      a) liberty -- free to do that as you please
      b) gratis -- something for no cost.

      Think of the (as beer) as a casting operation to the free word.

      People will often say free(libre) or free(gratis), but more often, it is just easier to say free(as beer) 'cause who would turn down free beer?

      And finally, how can someone who has such a low slashdot ID not have picked these things up? Have you been pouring hot grits down Natalie Portm
      • Think of the (as beer) as a casting operation to the free word

        Of course! It's not clear until it's expressed as a computer science concept, naturally.

        It still doesn't feel natural to me, since I can't think of a case where the sense of "free" isn't implicitly understood. In most cases it's an object that is free(beer). Of course, you could talk about it being free(libre) to do something or other... but that would be anthropomorphizing an inanimate object, and they hate it when you do that.

        Except, of cou
    • Sometimes beer is free. Like if you go to a party with no cover. Or at mug night (buy the mug for $5, the beer is free for X hours). Or a barbecue where someone else brings the beer.

      It's a way of saying you're getting something for nothing. Of course, it comes with the knowledge that often you get what you pay for (ie, free beer might be crappy beer).
    • Well, think about what beer would have to be like in order to be free of charge: it would have to be crappy. In fact, it would have to be so bad that nobody would pay for it.

      So, when people say "it's 'free as in speech', not 'free as in beer'", what they're really trying to say is "it's free as in freedom, not free as in 'no charge'". In that context, "free beer" basically means "no charge, and it's really crappy", while "free speech" basically means "no restrictions, it's really good".

      Unfortunately, as t
    • 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.
    • Try wikipedia.org, it's the Free Encyclopedia on the net. They have a slashdot section where they explain all this stuff.
    • Your user ID is too low to ask a question of this sort!
  • by SchnauzerGuy ( 647948 ) on Thursday September 04, 2003 @01:01AM (#6866308)
    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 [ramseyelectronics.com] to have a transmitter kit, but all they seem to have these days is a semi-cheesey 'cube' transmitter [ramseyelectronics.com]. 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 [abra-electronics.com] other [electronickits.com] kits [gatewayelex.com]. 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.
    • Out of all the suggestions on this page, I like this [gatewayelex.com](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 is

      • I wonder if the cheapest and most expedient solution is to just sign up for Channel [channelone.com] One [commercialalert.org] and then cancel it after a year. TV's for every classroom and free CCTV wiring to boot! No messing with open RF broadcasting. No pissing off the neighbors with interference.

        • We've got that already. We have the equipment and do broadcasts live every morning from the same room as the channel one box. The thing is we want to be able to broadcast from another room, thus be able to get the signal from the camera to the box.
    • See if you can get a grant for funding.

      When they renovated my high school, they installed a closed-circuit TV system in the building. Every room had a cable drop and a ceiling-mounted TV, and in the administration building there was an equipment rack that contained a number of RF modulators so that the A/V people could transmit up to 4-5 different channels of custom content on any arbitrary channel they chose. One was used for live feeds (Assemblies in the auditorium, Friday-morning school newscasts), an
  • Huh? (Score:2, Insightful)

    So, let me get this straight:

    1: You use Windows Media Encoder/Player, and it works fine
    2: You come to Slashdot asking for a free (as in beer) alternative.

    Huh? You already have a free (beer) solution, so long as the server and client are running Windows (as they most likely already are). Now you want to find a free (beer) solution that's different? Why? Want better quality? Cross-platform support? Just hate Microsoft? These are important details overlooked in your post.

    BTW: With 802.11g, you can get aroun
  • Try VideoLAN [videolan.org]. Superior multiplatform support. They have two applications, VLS - Video Lan Server and VLC, Video Lan Client. Very nice and flexible.

    Open source and everything too :).

  • What's limiting you? (Score:4, Interesting)

    by Wonko42 ( 29194 ) <ryan+slashdot@wo[ ].com ['nko' in gap]> on Thursday September 04, 2003 @01:56AM (#6866540) Homepage
    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 [broadq.com] 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.

    • by Anonymous Coward
      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.
      • Still, 4Mbps is more than enough for high quality streaming video. Most people won't notice any difference between 2Mbps DivX/XviD video and DVD video unless they look really hard.
  • by curious.corn ( 167387 ) on Thursday September 04, 2003 @02:49AM (#6866718)
    ... 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.
  • by Zarf ( 5735 ) on Thursday September 04, 2003 @03:28AM (#6866821) Journal
    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.
  • by Yarn ( 75 )
    I've used ffmpeg [sf.net] so I can watch sports events at work. I record them at home and stream at realtime to my work machine over http.

    Just noticed their page is closed due to the patent thing. Try here [sourceforge.net]
  • Noone mentioned Mplayer [mp.dev.hu] and Video-4-Linux [exploits.org]
    You should find great helpon both the mailing lists and Mplayer is portable to windows so if your school mates are alarmed at the diffrence in Linux you can make them feel more at home.
  • Realvideo Helix Producer Basic is free for non-profit to a max of 1mbit.

    http://www.realnetworks.com/products/producer/ba si c.html
  • (Sort of related . .) It would be nice to have my cable TV come to the outside of my house, and then all the internal wiring (3 boxes for 3 sets) be replaced by wireless communication. Presumably this is possible now in various ways, but is it easy? Should I be pestering my cable service to offer it as an option?
  • There's this awesome way of broadcasting TV wirelessly - it's called "TV broadcasting".

    Seriously, by the time your get all the software set up, the players in place, everyone knowing how to click on the right thing, the bandwidth straightened out (you didn't actually think you'd get what the spec claimed it could max out at did you?) plus dealt with network congestion, codecs, encoding servers, weird antennae patterns, dead spots, hand-offs, enabling multicast... You'll be graduating.

    Buy a small TV tran

    • We have TV equipment. There is a box in the library to broadcast to a TV in every classroom over a closed circuit system. No one would be clicking on anything. It would go from a computer w/ a firewire camera on it at location A, to a computer in our studio. The computer connects to the broadcast box via RCA. DOne.
  • xhost +<ip_of_machine_with_cam>
    ssh <ip_of_machine_with_cam>
    export DISPLAY=<ip_of_machine_with_tv>
    xawtv

    As far as I know this is the only way to minimize the delay to something between 20ms and a whole second.

    You could try something like Helix from real but you will experience a delay anywhere between 10 and 30 seconds. Mainly because the player wants to have a buffer to buy time if the network craps out. Probably every streaming technology has this but maybe there's one who can cope

  • I'd like to clear up one thing.

    The purpose of this setup is to get the video from the camera to a transmitter we already have, courtesy of Channel One. The problem is you need to be directly connected to the box with RCA cables, so obviously we can't be running RCA cable all over the building. Therefore we would just use computers to relay the signal from a computer the camera is on to a computer with RCA output
  • I am assuming that your school has a CATV drop in every classroom, including the one you want to broadcast from, correct? If the splitters used to distribute the RF signal from the MDF (Main Distribution Frame, where the box with RCA's currently is) are hybrids (read: also combiners), all you have to do is connect the RF modulator to the CATV drop in the room you want to broadcast from, and you're set. If that isn't the case or, for some reason, you need to send the signal to the MDF room first (like for ef

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