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DVB-T TV picture quality

Discussion in 'Microsoft Windows' started by Plobelle, Sep 14, 2005.

  1. Plobelle

    Plobelle
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    I have read vast amounts of useful and detailed information about picture quality on this and other forums but am still confused. What I am unclear about is what control one has over PQ when using MCE and DVB-T. For example I suspect the Hauppage tweak tools apply only to analogue/PVR solutions - is that right?

    I have an Elonex Artisan PC with MCE 2005, two Hauppage Nova-T tuners, ATI X300 grahics, latest (5.8) ATI drivers, connection via VGA into Panasonic TH42-PWD3. The screen is native 852x480 but I have the desktop set to 1280x720.

    The TV picture quality is tolerable but disappointing. Compared to my Sky+ (connected to screen via S-video) the PC picture is much less sharp, slightly blurred.

    The Hauppage tweak tools seem to have no effect. I can't find anything in ATI Catalyst or Powerstrip to affect sharpness.

    What are my options folks?
     
  2. chuckalicious

    chuckalicious
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    Not sure if this is it, but I recently discovered you can't really play with the picture quality settings too much when using digital terrestrial, because it's already encoded in MPEGII format, meaning MCe doesn't bother doing anything other than saving the feed as a file.

    I don't think comparing Sky to Freeview is really all that good a comparison. Freeview is for the time being using a small amount of over the air bandwidth, shared with analogue terrestrial, whereas Sky has it's own dedicated signal so the same channel may be getting broadcast at a higher or lower bitrate depending on what medium it's being broadcast on.

    I've noticed there is some digital artefacting on Freeview, both over set to boxes and my own Black Gold DVB-T card in my MCE machine.

    As far as I'm aware, there is very little you can do about it, because it's down to the way it's broadcast. Until they turn off analogue in 2007-2012 you won't get as great a picture as Sky I'd say.

    However in saying that, there is a registry entry somewhere on the green button forums, here: http://www.thegreenbutton.com/community/shwmessage.aspx?ForumID=42&MessageID=97920

    I tinkered with it a little and wasn't sure if I saw am improvement. Give it a shot, just change it back if you don't see any difference :)
     
  3. meansizzler

    meansizzler
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    Well freeview is broadcasted at low bitrates like 2mb-4mbs, whereas sky and other dvb sources use the 6-12mbps bitrate, I think, so poor quality video may look ok on sky but when you watch it on freeview it will look pretty crappy due to the low bit rate they use, try watching a music video on the Hits and you can tell....where as stuff that is shot at good quality like "Lost", looks ok on freeview even though it is being transmitted at a lower bitrate than sky...., and the end of the day freeview is never going to look that good, so it's really down the the way the show is shot, if more of them are shot in hi-def like "Lost", then the mpeg 2 transfers will look ok even on freeview but reruns of old shows are always going to look crappy....casue they were shot crappy....sucks doesn't it?...
     
  4. Plobelle

    Plobelle
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    Thanks for the replies. I tried increasing the DefAvgBitRate registry setting but couldn't detect any difference.

    Guess I'll just have to choose between better Sky PQ and paying Mr Murdoch lots of money each month (for Sky+ functionality even if not for premium channels) or lower PQ and money saved for future gadgets.
     
  5. nigelbb

    nigelbb
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    The bit rate of DVB-S isn't that much higher than DVB-T (Freeview). You can see this with the BBC & other FTA channels which you can play & record on a PC with a satellite card. In this case just like Freeview the MPEG2 stream is recorded directly to disk.

    I suspect that feeding a non-native resolution into the panel with downscaling is going to degrade the picture quality. Try recording a DVD of one of your recorded TV shows & then playing that back on a standalone DVD player to confirm whether it's Freeview or your TV-out.
     
  6. evolution400

    evolution400
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    And also means as your native res is 852*480 and your running 1280*720 the picture is obviously not going to be as good as if you were running native res try the native res or as close as possible then compare your picture quality.
     

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