Dismiss Notice
Attention AVForums app / Tapatalk users
Sadly GDPR means that, from 25th, we can no longer offer access to AVForums via the branded app or Tapatalk.
Click here for more information.

720p 1080i switching (hardware/Sky)

Discussion in 'General TV Discussions Forum' started by wilno, Aug 19, 2005.

  1. wilno

    wilno
    Standard Member

    Joined:
    Feb 14, 2005
    Messages:
    18
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    1
    Ratings:
    +0
    I currently own a sharp xvz2000 PJ (720p/native) which I have hooked up to:

    Sky+ and my home computer (using Theatertek)

    Sky via component and the PC via a really long DVI cable (which works flawlessly by the way, so never be put off) :cool:

    At the present I get my HDTV stuff from (somewhere else) but with Sky finally getting round to it maybe that will change. ;)

    To view the 1080i files I find the best method is to reset the PC from 1600x1200 to 1280x720 and let the PC do the scalling to the PJ. Otherwise (say using VLC) the PJ downscales from 1080 to 540p then upscales to 720 (p?).

    Both look great don't get me wrong, but the scalling from the PC Is better.

    Two Questions

    Will Sky offer this scalling? - American hardware I belive has this switching ability :confused:

    Will I be able/ is it going to be possible to feed Sky through a Home PC to achive a similar result if not?


    Thanks (hope some of that made sense)!

    ATB

    Wilno - not to be confused with my brother Wino :devil:
     
  2. Joe Fernand

    Joe Fernand
    Distinguished Member AVForums Sponsor

    Joined:
    Jan 20, 2002
    Messages:
    26,765
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    The Borders
    Ratings:
    +3,088
    Hello Wilno

    I believe SKY will simply offer the option for each channel broadcaster to transmit 1280x720P or 1920x1080i and whatever format they chose is the one the box will output - if you want to convert 1080i content to 720P ahead of your Display device you will require a Video Processor that can undertake that conversion.

    Best regards

    Joe
     
  3. Stephen Neal

    Stephen Neal
    Well-known Member

    Joined:
    Mar 29, 2003
    Messages:
    6,371
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    133
    Ratings:
    +820
    You may be right - however if the Sky boxes behave as US DSat boxes do you may also find that you can run your box at a fixed output resolution (say 1080i or 720p) and have the receiver scale. Given that the chipsets for UK HD boxes are likely to be closely related to those used in the US (DirecTV in the US is going MPEG4 as well) it may be they offer the same facilities. In the US it is more common to find 1080i/480p/480i only displays - with no 720p capabilities, so I wouldn't be surprised.

    Don't forget the box has 3 resolutions to cope with - 576/50i, 1080/50i and 720/50p - as it will be standard def capable as well.

    If the box can run at a fixed resolution output there are major ergonomic advantages - as channel surfing between channels of differing formats may be quicker if your display doesn't have to keep altering to a different input format (probably accompanied by lovely on-screen graphics)
     
  4. richard plumb

    richard plumb
    Well-known Member

    Joined:
    Jan 27, 2002
    Messages:
    14,477
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    133
    Location:
    Windsor
    Ratings:
    +1,046
    I certainly hope so, as my screen only takes 1080i.

    If they could guarantee HD Ready sets only, then they could switch the outputs (and save on some scaling hardware), but they have to deal with normal TVs (so at least a basic scaler is needed) and component HD.

    I want to tell it I have a 1080i only set, and therefore I only want 1080i out of it.


    BTW what will happen with SD content? my screen doesn't take 480 or 576i, so would the box upscale SD to 1080i as well? (me slowly realising I'm most likely stuffed)
     
  5. Stephen Neal

    Stephen Neal
    Well-known Member

    Joined:
    Mar 29, 2003
    Messages:
    6,371
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    133
    Ratings:
    +820
    I suspect the SD output on Sky boxes will be independent of the HD output (so that SD is present irrespective of the HD output, to allow VCRs and DVD recorders to record shows still) - so any downconversion scaler will be separate to any cross/up conversion one.

    I wouldn't be at all surprised if basic cross/up conversion and simultaneous down conversion was standard in the MPEG2 (and MPEG2/4) decoder/output chips in use in set top boxes. It is so common in the US I would be surprised if it required lots of extra processing to be added internally to the box.

    However the de-interlacing from 50i to 50p may not be the highest quality - and external scalers may be better at this.
     
  6. wilno

    wilno
    Standard Member

    Joined:
    Feb 14, 2005
    Messages:
    18
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    1
    Ratings:
    +0
    Thanks for replying,

    Here's hoping the box will be all singing and dancing offering the consumer a never seen before array of features. Yeah right :lease:

    Seriously though, if the cheaper option for them is to base the new box on American hardware already out and proven (with reciever scalling) this must surely be a better deal for all.

    Regards

    Wilno
     
  7. nicke20

    nicke20
    Member

    Joined:
    Oct 11, 2003
    Messages:
    885
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    21
    Ratings:
    +13
    didnt I hear that thompson where making the boxes ?
     
  8. Stephen Neal

    Stephen Neal
    Well-known Member

    Joined:
    Mar 29, 2003
    Messages:
    6,371
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    133
    Ratings:
    +820
    Yep - though I suspect the chipsets used will be the same for MPEG4 boxes sold in Europe and the US (where MPEG4 is also being adopted). They could easily be developments of HD MPEG2 chipsets and offer similar functionality.

    Whilst Thomson is a French company - I believe they also own RCA in the US - who manufacture(d) ATSC receivers for the US HD market?
     

Share This Page

Loading...
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice