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HDTV and the Propeller — Parallax Forums

HDTV and the Propeller

LoopyBytelooseLoopyByteloose Posts: 12,537
edited 2010-09-29 08:54 in Propeller 1
I am a bit confused about the future of TV and how it affects my Propeller video projects.

With the Propeller, we have NTSC/PAL video which is 7 times slower than VGA and allows a lot more headroom for nifty code than VGA video.

And of course we have VGA video that is probably the easiest to comprehend for study.

But the future seems to belong to HDTV and digital transmission. I've been trying to figure out if I can purchase a new TV for both viewing and NTSC/PAL video projects. I realize this may seem a bit of a stupid question, but living in Taiwan means that I don't get technical answers from salesmen - their eyes glaze over and they just keep asking if I want to buy this or that.

BTW, I can buy a nice VGA monitor for about 50% of what a similar sized flat panel TV costs these days. Of course I could by a huge color tube TV for the same price as the flat panel VGA, but I want a small footprint, less clutter.

Comments

  • Peter KG6LSEPeter KG6LSE Posts: 1,383
    edited 2010-09-27 09:23
    99% of TVs will support NTSC CCIR 601 for years to come .

    as long as there is composite input jacks there will be support :)
    The video is just scailed in a ASIC in the TV.
  • RaymanRayman Posts: 14,889
    edited 2010-09-27 10:16
    There's chip TFP410 that can convert VGA to DVI/HDMI...

    I started looking into this a while ago, but didn't find time to get higher resolution VGA working:

    http://forums.parallax.com/showthread.php?t=117342&highlight=tfp410
  • Invent-O-DocInvent-O-Doc Posts: 768
    edited 2010-09-27 14:29
    As long as you have composite input, you will be ok with NTSC or PAL. Other than that VGA works pretty well and you can use the Prop I for some handy hi-resolution text displays.

    If you want to do some modest HDTV graphics, you will like the Propeller II.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-09-28 00:51
    Thanks, I will take a good look at the plug-ins on anything I do buy. It is about time that I have a larger screen for NTSC/PAL projects.
  • Cluso99Cluso99 Posts: 18,069
    edited 2010-09-28 01:45
    I agree we will see composite input for some considerable years to come. A lot of TVs also come with VGA these days too.

    Or, as you said, a cheap VGA LCD just for the prop is cheap too.

    Beware of the hype for HDTV. SD transmission will also stay as there are less HD channels than SD channels and more SD channels are being added regularly. That does not mean I would buy an SD TV now, but it does mean that you will regularly viewing SD shows.

    So, in summary, the prop will have plenty of devices to display its data on for years to come.
  • RaymanRayman Posts: 14,889
    edited 2010-09-28 05:54
    I'd also guess that TVs will have analog input and computer monitors will have regular VGA input for a while...

    I would really like to get a HDMI/DVI output working, nevertheless...
    The picture is razor sharp, the color fidelity perfect, and there's no need to adjust the screen.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-09-28 07:28
    This all begs the question of whether the Propeller will ever do HDTV and other digital TV formats.
  • wjsteelewjsteele Posts: 697
    edited 2010-09-28 08:20
    The Prop II is designed for HD. ;-) If I said that it was impossible for the Prop I to do HDTV, someone will turn around and do it. It's happend with several other impossible technologies in the past.

    So... IT IS IMPOSSIBLE FOR THE PROP I TO DO HDTV!!!

    Bill
  • RaymanRayman Posts: 14,889
    edited 2010-09-28 10:56
    I think it's not too hard, depending on what you want to call HD...

    As I recall, somebody converted the 1280x1024 VGA driver to 1280x720.
    You could call this 720p.

    Splice in the TFP410 and then you have it with digital transmission.

    I talked to Chip briefly about the Prop2 and HDMI and it seems that the data rate is too high even for the Prop2 to do native digital transmission.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-09-29 07:08
    Excellent, time to really commit to comprehending video on the Propeller. Now if I could just find where I put my Hydra board I'd be in great shape.

    I have gotten PAL and NTSC color bar tests working with my video box that feeds TV to one of my VGAs. But I do want to get a real TV.

    NOW I am very curious what the Propeller TWO will actually do. Digital video is finally heating up again as a technological leading edge.
  • ericballericball Posts: 774
    edited 2010-09-29 08:54
    wjsteele wrote: »
    The Prop II is designed for HD. ;-) If I said that it was impossible for the Prop I to do HDTV, someone will turn around and do it. It's happend with several other impossible technologies in the past. So... IT IS IMPOSSIBLE FOR THE PROP I TO DO HDTV!!!
    The spirit is willing but the flesh is weak.

    Broadcast HDTV in North America uses 8-VSB modulation with a 10.76MHz symbol rate (8 levels/3 bits per symbol). This actually lines up nicely with the typical Propeller baseband video DAC. (It might even be possible to use broadcast mode to perform the necessary AM modulation.) So each WAITVID would output 4 symbols (as luma only, no chroma) for a pixel frequency of 2.69MHz. At 80MHz that gives the Propeller 29.74 cycles per WAITVID. That gives just enough cycles to execute RDLONG+WAITVID, but not enough to add any JMP/loop.

    This is also just the output stage and it assumes the rest of the signal processing has been done, including: MPEG video & audio compression & MPEG-2 transport stream creation (187 byte packets at 19.39Mbps), data randomization, Reed-Solomon Error Encoding (20 bytes per packet), data interleaving (time diversity), trellis encoding (2 to 3 bit encoding) and sync insertion (1 field sync packet per 312 packets & 4 symbol segment sync per packet).

    Of course, this is only one method of generating HDTV output.
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