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Television Media

DirecTV's 1st MPEG4 Satellite Launch Successful 291

tivoKlr writes "Looks like the 1st Spaceway satellite to provide "1500 channels of HD" has made it successfully into space. MPEG4 compression and local HD channels, something that the cable company can't offer in my area." Unfortunately the new satellite obsoletes the HD Tivo, and there's no word on when there will be a new one.
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DirecTV's 1st MPEG4 Satellite Launch Successful

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  • by Dios ( 83038 ) on Wednesday April 27, 2005 @09:48AM (#12358399) Homepage

    I believe the High Def Tivo uses MPEG2 for its data streams, won't be capable of decoding the MPEG4 streams.
  • by Anonymous Coward on Wednesday April 27, 2005 @09:49AM (#12358417)
    Note that comm satellites are just 'bent pipes'. This keeps them simple and independent of changing technology. So, there likely isn't any MPEG4 technology on board the satellite. Rather, the technology will be in the ground station. Therefore, DirecTV could have used an existing satellite in orbit, or even shared space with someone else on a satellite...
  • by gevmage ( 213603 ) * on Wednesday April 27, 2005 @09:54AM (#12358446) Homepage
    Digital TV has 18 different formats (resolutions), 6 of which are considered "HD". A couple of them are equivalent to NTSC resolution; 640x480 pixels. So NTSC stuff would presumably be broadcast in the standard appropriate digital format, taking up less bandwidth than one of the HD formats.
  • by skaeight ( 653904 ) on Wednesday April 27, 2005 @10:00AM (#12358511)
    I will confirm that a software update will not allow an HDTiVo to decode MPEG-4. TiVos are very low powered devices, and thus use hardware decoder chips, not software decoding. So they have an MPEG-2 decoder chip to complement a comparibly underpowered CPU. They can't simply push a new codec down to the TiVo to decode MPEG-4.

    HD DirecTiVos will be obsolete next year.
  • by jchapman16 ( 300859 ) on Wednesday April 27, 2005 @10:06AM (#12358558) Homepage
    Note that cable providers recompress the original MPEG2 streams themselves to reduce bandwidth used by HD channels.
  • by skaeight ( 653904 ) on Wednesday April 27, 2005 @10:07AM (#12358577)
    Actually, no they couldn't have. For one reason. Bandwidth. They are completely maxed out right now. They couldn't have added 1 more HD channel, let alone 1500 additional HD channels. Each HD channel is something like 15 SD channel.

    The only reason they are able to do this is because they are going to be transmitting using a different band - KA. The current DirecTV sattelites transmit in the KU band. So they'll be using their existing orbital slots 101, 110, & 119 to broadcast on a different wavelenght.

    Unfortunately this is going to be mean a larger dish will be required. Google dish network superdish for an idea of how big it is. Dish Network already does broadcast some local channels in KA band.
  • by flimflam ( 21332 ) on Wednesday April 27, 2005 @10:09AM (#12358594)
    Yes, though not at the specific data rates used for broadcast. In general MPEG4 is vastly superior to MPEG2, however. Also, an MPEG2 stream would never be recompressed as MPEG4, the broadcaster would feed the uncompressed signal into the MPEG4 compressor. All in all this is a move to increase quality at the same bandwidth.

  • Ka spot beams (Score:5, Informative)

    by TheSync ( 5291 ) on Wednesday April 27, 2005 @10:09AM (#12358595) Journal
    The "killer technology" on the Spaceway birds are their ability to form tight "spot beams" using Ka band (~20 Ghz) downlink signals.

    The spot beams are formed using a 1500 element phased array. The array can form as many as 780 downlink spot beams and 112 uplink spot beams across the US. Compare this with a typical Ku-band (~12 GHz) satellite which has a single beam over the entire US.

    Spaceway uses digital regenerative switching of up to 10 Gbps, as opposed to the analog transponders of most geosynchronous communications satellites (despite the fact that most of those transponders are used with digital services these days).

    Spaceway was originally supposed to provide satellite point-to-point and point-to-multipoint IP connectivity, but that was dropped in favor of providing massive localized HDTV capacity using spot beams.

    Unfortunately, Ka band is more sensitive to rain fade outages than Ku band.
  • Re:Full HDTV Finally (Score:2, Informative)

    by BraceletWinner ( 845950 ) on Wednesday April 27, 2005 @10:24AM (#12358740) Homepage
    Dish Network bought the Voom satellite, so you may be able to get those channels on Dish soon.
  • by Sc00ter ( 99550 ) on Wednesday April 27, 2005 @10:25AM (#12358754) Homepage
    DirecTV doesn't want to use TiVo anymore, they are developing their own "Home Media System" or something like that to replace the HDDirecTiVos. It is of course not released yet.

  • by TheSync ( 5291 ) on Wednesday April 27, 2005 @10:37AM (#12358900) Journal
    Spaceway uses digital regenerative switching, so it is not at all like typical geosync comm satellites. But you are right, there is nothing about MPEG-4 on the satellite, it could very well be switching MPEG-2 coded video or even IP (its original mission).

    The funny thing is that MPEG-4 streams are carried within the same 188-byte packet MPEG-2 transport stream that normal MPEG-2 live video streams use.
  • by TheSync ( 5291 ) on Wednesday April 27, 2005 @10:40AM (#12358940) Journal
    19 Mpbs is the standard (ATSC) for US digital terrestrial HD broadcasts. But trust me, HD looks a lot better at 270 Mbps (HDCAM) rates...
  • by Satan Dumpling ( 656239 ) on Wednesday April 27, 2005 @10:43AM (#12358987) Homepage
    Most of what they have was filmed in 4x3. The major networks are not going to suddenly limit themselves to only 16x9 and change their whole schedule. As more and more new episodes are filmed in 16x9 you'll see more.
    Comcast near Atlanta just added TNT in HD. For some reason they are stretching all 4x3 into 16x9. Now that's REALLY annoying.
  • Re:Full HDTV Finally (Score:3, Informative)

    by cdrudge ( 68377 ) * on Wednesday April 27, 2005 @11:10AM (#12359362) Homepage
    Dish is buying the satellite and the uplink facility. However the content and encoding equipment wasn't included in the deal (yet..stay tuned though ;) )
  • Re:Ka spot beams (Score:5, Informative)

    by Anonymous Coward on Wednesday April 27, 2005 @11:14AM (#12359415)
    Disclaimer, I work on the SPACEWAY project. The rain fade is mitigated by constant updates of weather data (we're talking Gigs per day of data transfer). This data is used to tell the satellite where to pump up the signal to get through the clouds. Areas of clear sky get the signal reduced. This helps deal with rain fade and also prolongs the life of the satellite since it keeps power consumtion low.
  • Watch the launch (Score:2, Informative)

    by Anonymous Coward on Wednesday April 27, 2005 @11:18AM (#12359483)
    The launch can be seen at the Sea Launch website www.sea-launch.com [sea-launch.com] This was the heaviest launch for Sea Launch to date.
  • Re:Full HDTV Finally (Score:3, Informative)

    by MindStalker ( 22827 ) <mindstalker@@@gmail...com> on Wednesday April 27, 2005 @11:29AM (#12359672) Journal
    DirecTV is offering a $200 rebate for voom customers looking to move to DTV.
    http://www.directv.com/voom/
  • by RzUpAnmsCwrds ( 262647 ) on Wednesday April 27, 2005 @12:44PM (#12360689)
    "Any "visualphile" will know that a decent analogue signal usually looks a lot better than it's digital equivalent (ref: I'm comparing Digital Terrestrial to Digital Satellite and Cable services available in the UK)."

    No, it doesn't. A clean analog signal looks better than an overcompressed digital signal, true. But a truly "clean" analog signal doesn't exist.

    Compare the quality of DVD to the much-vaunted Laserdisc. LD is about as close as you can get to a "clean" analog signal, and it still had a number of quality issues (mostly related to color-space compression).

    "They don't seem to be able to transmit TV in the current resolution without severely degrading the picture."

    Evidently your cable and satellite providers in the UK suck. They do here, too. DirecTV's picture is already overcompressed garbage.

    That's why we're so psyched about SPACEWAY - there's plenty of bandwidth to transmit every local channel in the US, in HD, with a decent bitrate.

    "My worry is that even with MPEG 4 (which will probably be recompressed MPEG 2 sources anyway for quite a while) they may not have enough bandwith to send me a 1080 line picture without artifacts..."

    There is plenty of bandwidth with SPACEWAY. Bandwidth will now be in the 10-12MBit range, up from 1-2MBit for DirecTV's current SD service. They're using MPEG-4, too, so that provides an additional quality increase.

    If you're worried about 1080i looking poor at 12MBPS, keep in mind that Microsoft's WMV-HD demos (at 1080p, no less) are in that range. Go download one and take a look for yourself.

    DirecTV also won't be re-encoding MPEG-2 boradcasts - they will get a clean signal that they can encode, just like they do today with MPEG-2.

    "Maybe with Fiber To The Home we might actually get enough bandwidth to watch the channels we want at the resolution we want, without thinking that it looks like your TV has gone though 4 copes of RealPlayer..."

    FTTP is completely unnecessary for the cable company. The coax they have in the ground right now is already capable of delivering 120+ HD channels at full broadcast bitrate (~20mbps). That's only counting the spectrum they are currrently using for analog channels.

    There's plenty of bandwidth with the current coax. There's no need for FTTP just to get decent HD services.
  • by Inebrius ( 715009 ) on Wednesday April 27, 2005 @01:02PM (#12360912)
    If I was a DirecTV customer, I would care, as do many others.

    I do not live in a major metropolitan area, so I do not get a very good signal (analog or digital) from the local stations. Many people also have issues due to terrain. With satellite, line of sight is much better (either you get it or you don't), and barring severe weather, the signal is much more dependable.

    I currently get my locals on Dish, just not in HDTV. And due to market rules, I do not qualify to receive the distant network HD feeds. So if they did add locals in HDTV, it would be an appreciated increase in service.
  • by Xesdeeni ( 308293 ) on Wednesday April 27, 2005 @01:10PM (#12361021)
    RawDigits: I would imagine an operation as large as DirecTV is probably not going to be re-encoding an MPEG2 signal, but using a more raw format for HD and compressing it from the 'master' copy just as they do when they convert to mpeg2 now ...

    mecro: The FCC only gave broadcasters a small chunk of the spectrum to broadcast, which means the MPEG2 signal is compressed somewhere between 49-55:1.. That's insane, and MPEG 4 will hopefully lessen the compression ratio.

    flimflam: Yes, though not at the specific data rates used for broadcast. In general MPEG4 is vastly superior to MPEG2, however. Also, an MPEG2 stream would never be recompressed as MPEG4, the broadcaster would feed the uncompressed signal into the MPEG4 compressor. All in all this is a move to increase quality at the same bandwidth.

    For OTA signals, DirectTV and Dish currently have an antenna in the city that receives the analog OTA signal, which they compress for transmission. They only have a direct connection to the national signals they provide to people too far from local affiliates (I believe from NY and LA). It's unlikely they will obtain a more direct connection for digital OTA signals. So it's almost certain that the video will be doubly compressed--MPEG-2 by the channels, MPEG-4 by DirectTV.

    Satellite channels (ESPN-HD, etc.) are currently pulled off of the high bitrate (MPEG-2) satellite feeds and compressed to low bitrate MPEG-2 by DirectTV and Dish. The encoder will likely be MPEG-4 for these types of sources.

    jchapman16: Note that cable providers recompress the original MPEG2 streams themselves to reduce bandwidth used by HD channels.

    I can't speak for every cable provider, but stream analysis done by those of us with FusionHDTV cards (capable of recording cable's QAM modulated HD streams) have shown that the video is not recompressed. It is re-wrapped, with much of the transport stream adjusted, but the data itself is not decompressed and re-compressed.

    Xesdeeni
  • by dcm1101 ( 71726 ) on Wednesday April 27, 2005 @01:46PM (#12361461)
    Well, there are web sites [satsig.net] that allow you to enter your latitude and longitude and the orbital slot of a satellite, and then they do the math for you to get the azimuth and elevation. Or if you're a math geek, you can do the math [bizhat.com] yourself. Then, if you had an extremely accurate compass/inclinometer [knowareland.com] you could try to aim the antenna that way. In actual practice, I doubt that would work reliably - hitting a target the size of a car from 22,000 miles away is a very touchy business. Most pros use a compass/inclinometer to get to the right portion of the sky, and then hook up a spectrum analyzer [sepatriot.com] to find the nearest satellite, and then 'stair step' across the arc until they find the bird they want. Being able to ID a satellite by its spectrum plot is a little bit of an art, but allows you to at least confirm that you're looking at a satellite. You can always hook up your IRD at that point to check of it's the right satellite. The problem with just tuning using your receiver on a digital signal, is that below a certain threshold the signal will not lock up, so be prepared to spend all day moving your dish 1/4 of a degree at a time, and waiting 30 seconds after each move to see if it locks up.

    Ironically, the smaller dishes are easier to aim, since their gain is so much lower. Remember, a satellite dish is simply a telescope that operates on microwave frequencies rather than visible light, so a more powerful antenna "sees" a much smaller portion of sky, and consequently gets a much better signal. Having aligned 1.6-meter dishes and 12-meter dishes, I can attest that the 12-meter gets a great signal, but is harder to aim.

  • clueless (Score:1, Informative)

    by Anonymous Coward on Wednesday April 27, 2005 @01:46PM (#12361469)
    The DVD standard is MPEG2 at either 720x480 (NTSC) or 720x576 (PAL). That's 480 or 576 lines, respectively. DirecTV is (currently) MPEG2 at 480x480.

    HDTV is 720 lines or more. DirecTV is converting to MPEG4 so it has the bandwidth to broadcast more channels at HD resolutions. At least initially, only HD channels will be broadcast with MPEG4.
  • by Snwbeast ( 21484 ) on Wednesday April 27, 2005 @02:22PM (#12361910)
    I've gotten to see a little bit of this, since my company (TandbergTV) is supplying the encoders. The bitrates on the mpeg-4 stream are going to vary from 4mbps to 20 mbps, which in mpeg-4 is pretty good looking. There's a load-balancing system that will adjust a channel's bitrate as it needs more (for say fast-panning scenes in sports). The encoders are installed now in two locations and running, but as with all projects this will take time.
  • Re:Let's see... (Score:3, Informative)

    by Keith Russell ( 4440 ) on Wednesday April 27, 2005 @03:54PM (#12363365) Journal

    Most of the issues you raise in point 1 deal with the transition from NTSC to digital in general. The monitor is still the largest single expense, so it doesn't matter if the transmission medium is OTA, DBS, or cable. And there should be exactly one encode at the uplink/headend, and one decode at the customer's tuner. If your provider of choice is recompressing mid-stream, they've screwed something up.

    These gaming and information services you speak of are already the norm. Perhaps you've heard of the Internet and XBox Live? Maybe if customers were demanding One True Set Top Box that has all these features, you'd have a point. More likely, these features are being crammed into STBs the way Microsoft would cram features into Office, just so they can brag that the "other guys" don't offer Esoteric Feature That Nobody Asked For #7.

    Do you honestly think that cable will have a better track record than DBS on DRM? Name-dropping Rupert Murdoch and Circuit City DiVX won't change the fact that DBS and cable providers will all answer to the Big Media content providers.

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