Bitrate on SD programming?

Discussion in 'DISH™ High Definition Discussion' started by IDRick, Apr 23, 2008.

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  1. IDRick

    IDRick Godfather

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    In one of today's threads, a poster stated that SD programming typically averages a 0.5 to 2 bitrate (Mpeg 2 file). Yikes, is this really true? I've not seen Dish SD but I do know that my results from my DVD recorder are horrendous at that bitrate. My normal recordings are typically have a bit rate of 4.5 to 6.0. If the posted bit rate is correct, then SD must be really bad on a large screen.
     
  2. LinkNuc

    LinkNuc Legend

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    It's certainly not the best, I have a 60" screen and itts by far the worst SD PQ I have ever seen (I have had D*, Comcast and TW)
     
  3. ICBM99

    ICBM99 Mentor

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    I've got a 60" screen and don't think SD looks too bad. Sure its soft and "fuzzy" sometimes. My locals are the worst, but I think its the broadcasters not E*.

    Keep in mind that all I've ever had has been Dish, so I have nothing to compare to. YMMV
     
  4. Mr.72

    Mr.72 Icon

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    well, if DVDs are "SD", then the "SD" we get on dish is abysmal compared with the quality of "SD" on a DVD.

    it's different for different channels. The RSNs are among the worst. Many channels just look so bad on dish I cannot even tolerate watching them. They look sort of OK on our old direct-view 25" SDTV and my kids watch them without complaining but they are really horrible on our main TV.
     
  5. mattfast1

    mattfast1 Legend

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    Hmmm... since DVDs are 720p, and SD TV is 480i, I would say a DVD would be a little better than SD, wouldn't you?
     
  6. IDRick

    IDRick Godfather

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    Hmm, aren't dvd's 480i? My dvd recordings are 720 by 480 and my DVD player displays them with 480p. Newer dvd players with HDMI outputs upscale to near HD but I'm not sure of their specs. Also, I use Video Redo to downconvert 1080i clear QAM recordings down to 480i and then burn to DVD for archival purposes.
     
  7. tnsprin

    tnsprin Hall Of Fame

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    In some cases the source material is 480P (or higher), although encoded on DVD's as 480i. A simple process can than return it to 480P. Others, particularly those done with SD Video, are truly 480i.

    Note that for 480P material it is possible for DISH to do better encoding and reduce the bit rate if they actually send it out as 480P. I Don't think they have started to do this yet for MPEG2, but they probably will be doing it for MPEG4.
     
  8. IDRick

    IDRick Godfather

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    Yikes! One of my primary motivations for considering a switch to dish is the potential to watch more college hockey on FSN North and BTN. PQ from my cableco on this SD material is above average (compared to other SD programming). If the PQ is poor on RSN's, then I really need to stay with cable. I don't want to sign up for a two year commitment and then lose the ability to watch college hockey due to low PQ....

    As an aside, this winter I went over to CC and happened to stop by the D* display. I was able to try out the D* HD DVR and check out searches, etc. I found a college hockey game in progress on a midwestern RSN. Yikes, horrible quality. In fairness to D*, I need to point out that the SD was stretched to fill a 32" widescreen and it wasn't a name brand TV. But, HBO HD looked awesome on this same tv...
     
  9. IDRick

    IDRick Godfather

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    Feb 15, 2007
    Thanks for info tnsprin! I must admit that I'm leery about making a change. On one hand, I like the potential programming that is available from Dish but I don't have first hand experience with evaluating Dish's PQ on both HD and SD. Any suggestions on how I could do a comparison? One of my hunting buddies has a basic dish package and the 625 DVR. Would SD PQ be the same with a 625 versus a 722 DVR?
     
  10. Bichon

    Bichon Godfather

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    Yes, DVDs are 480i, 60 interlaced fields per second. If the original material was shot at 24 frames per second, a progressive scan player can use 3:2 pulldown to de-interlace it to 480p with no artifacts or loss of quality.

    But that's not the end of the "trickery" use to get better quality. Many widescreen films are put on DVD in anamorphic mode. That means that rather than wasting some of the 720x480 frame for the black bars above and below the picture, the content is stretched vertically to fill the entire 4:3 frame. Upon playback, the TV vertically squashes the picture back to the correct aspect ratio, but with much higher vertical resolution than it would have had if it were broadcast without the anamorphic process.
     
  11. P Smith

    P Smith Mr. FixAnything

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    Nowadays SD channels came from sat providers in 480x480 or 504x480 format ( numbers taken from real stream ).
     
  12. HDlover

    HDlover Godfather

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    I really doubt the bit rate is that low. The SD on my 73" isn't DVD quality but isn't "That" bad. Definitly watchable and much better than analog.
     
  13. P Smith

    P Smith Mr. FixAnything

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    Give me sat/tpn/ch# and I'll tell you the rates.
     
  14. tvjay

    tvjay Godfather

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    How do you get them?
     
  15. TP715

    TP715 Mentor

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    There are ways to read the data stream which I'm sure P Smith will explain.

    However, if you have an external hard drive you can easily estimate the bit rate of any show you record (and move to the HD) as it shows the MBytes the show uses up. Here are some random examples from my hard drive (in mega bits per second):

    HD Jeopardy about 6 Mbps
    HD Movies from various channels: about 5.0 to 8.3 Mbps
    SD Movies and TV shows, about 1.7 to 2.0 MBps
    SD show from second tier NPR station, 1.4 Mbps

    As you can see even the HD usually doesn't surpass what an SD DVD is encoded at and the SD is far, far below that rate.

    Doing these calculations gave a nice quantitative background to what I already saw with my eyes: the SD quality from Dish stinks and the HD quality is about that of good SD.

    (I'm sure someone is going to chime in that Mpeg 4 is much better at compression than Mpeg 2. Perhaps. Image quality still looks stinky to me though.)
     
  16. P Smith

    P Smith Mr. FixAnything

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    It's named as 'HD-Lite' :(.
     
  17. HDlover

    HDlover Godfather

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    2mbs, hmm, however these are converts of analog quality shows- stinks to begin with. Not convert of film like on DVD. It makes a big difference. I, myself, subscripe to the HD only package. All SD looks not very good in comparison and I avoid it as much as possible. Directv may be better, I don't know but it is still SD so who cares. This is the HD thread isn't it?

    I've had Comcast. Their analog is worse and their SD digital is worse than that. Now they are overcompressing their HD so they have nothing going for them.

    OP are you thinking of going to Dish? What do you have now? What size is your TY and is it HD?
     
  18. LinkNuc

    LinkNuc Legend

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    HD-Lite is really just the sats sending out 1440x1080i or 1280x1080i..then upconverted at the box which is the major reason cable (although they are starting too compress as well) FiOS and OTA have a better PQ...altough like I said Companies that offer the most HD like Comcast(On-demand etc) are starting to compress as well...
     
  19. P Smith

    P Smith Mr. FixAnything

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    HD-Lite doesn't limit a distortion of original source just by cropping , but by reducing bandwidth, overcompessing, etc.
     
  20. Slipshod

    Slipshod Cool Member

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    One thing to keep in mind is that the encoders used by the Satellite providers are *very* good at squeezing the highest possible picture quality out of the lowest possible bitrate. While it's fair to say SD PQ sucks, it is not fair to compare the bitrates they use against consumer-grade encoders you are used to. The PQ will be different at any given bitrate.

    Dish uses 544x480i (not 504) for most SD channels, but some of the locals are only 480x480i. Most of the shows I record seem to be about 2 Mbps (1 gigabyte for 1 hour), the exception being the 480x480i local PBS channels which are less.

    For HD, Dish sends it at 1440x1080 resolution for both MPEG4 and MPEG2 channels. They are flagged as progressive for the MPEG4 channels, but I haven't actually examined the video stream to verify it. For MPEG4 they seem to be in the neighborhood of 6-7Mbps for movies on MAX and Showtime, including the audio stream. I haven't checked MPEG2 as there isn't a whole lot left. I think HDNet Movies is still MPEG2.

    I've heard that DirectTV uses 480x480i for all SD, and 1280x1080 for HD. I don't know what bitrates it would be at, or if this is even correct as I don't subscribe to them.

    Cheers,
    Slipshod
     
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