[mythtv-users] Is the pchdtv card looking good?

[Steele Price]

Jarod C. Wilson wrote:

> On Tuesday, Sep 16, 2003, at 21:31 US/Pacific, Brandon Beattie wrote:
> 
>> On Tue, Sep 16, 2003 at 08:11:27PM -0700, Jarod C. Wilson wrote:
>>
>>>> I don't think you misunderstood.  I have saved MANY HD streams and they
>>>> all included 2 resolutions, 720p and 480i (this probably changes from
>>>> station to station)
>>>
>>>
>>> 720p and 480i?!? Is that HD and NTSC on the same channel? From what I
>>> can tell, all I'm getting over cable is 1080i HD, and those channels
>>> are on different channels than normal TV (ex: 31 = ESPN, 173 = ESPN
>>> HD). But of course, I have no way to capture these streams, so I can't
>>> really be sure what the tuner (Motorola DCT5100; I've had it a week
>>> now) is receiving. From what I understand, most HDTVs do 720p either.
>>> Most are 1080i and 480p for HD and 480i for NTSC, while some do 720p,
>>> and almost none do both 1080i and 720p...
>>
>>
>> A HD display device is one of the following.  1440x720 (720P), 1920x540
>> (1080i), 960x540 (1080i).  I have yet to see a 1920x1080 (1080/p) HD
>> display _being sold_.
> 
> 
> So what is the deal with me not being able to use videogen to create a 
> 1920x540 custom modeline to output to my TV? 960x540 doesn't work 
> either. I've been having a miserable time with this Audio Authority 
> adapter, but I don't think the adapter is the problem...

It's not the adapter, I have the same one, it's flawless for me, in fact 
it is excellent in terms of quality, it look every bit as good as DVI on 
everything but 1080i.

TVs are really pathetically tuned, what brand/model are you dealing 
with?  I have a Sony 34XBR800, I had to go into service mode and make 
alot of "adjustments" just to get things to output correctly, overscan 
settings were terrible, upper right corner was warping, convergence was 
off in a couple modes, and some just needed a little tweaking.

Modelines took me at least 2 days to finally get right, but I wanted 6 
resolutions.  I'm pretty certain that mine is optimized for 720p, at 
least it is the most clear from VGA to Component out.  However there was 
a 30 pixel overscan and it was making me crazy, I got it down to about 
10 pixels, but a tad more tweaking and I think I can get rid of it 
completely.

Tearing is another big problem spot for me and I haven't quite figured 
this one out yet, when myth goes into certain alpha modes it sends my 
display crazy with moire patterns, I am trying to find a service mode to 
fix that without trashing the tube.  Service mode can fix pretty much 
everything, but it can also send you tv into oblivion, so extreme 
caution is needed when using it.

> 
>> HD streams (ATSC) are 80% 1080i (1920x1080i), 15% 720p, 80% 480P
>> (720x480p or 640x480P).  Yes, this is more than 100% but this comes
>> because you have subchannels and 480p is often used while using a 1080i
>> or 720p stream.
>>
>> There will be a lot of you thinking this doesn't make sense, or it's
>> wrong.
> 
> 
> Makes sense to me (mostly ;).
> 
>> What you need to know is the DTV spec has about 16
>> "resolutions & frame rates" in it.  Your HD display will do _one_ of
>> them optimally and the others it will scale and modify to fit your
>> native HD resolution.
> 
> 
> I thought it was 18 different ones. At least that's how many I'm 
> counting at atsc.org right now... (well, okay, actually 16 claim to be 
> standards, one a proposed standard and one a candidate standard).
> 
>> Which is better?  Depends on your viewing habbits.  If you're a sports
>> fan, almost all sports are recorded in 720p because motion looks better.

the best resolution is going to be matching what is broadcast, that is 
if you tv can handle it.  Not all tvs are created equal and they usually 
don't support all resolutions.  Upscaling is always going to look bad. 
if you are watching a broadcast in 720p then viewing it at 1080i is 
going to be a drop in quality. Likewise for downscaling, however 1080i 
to 720 actually isn't too bad, much better than the other way around.

> 
> 
> Though the vast majority of HDTVs can't do 720p... Damn. I'm a sports fan.
> 
>> 1080i is better for overall "quality and sharpness".  Current 1080i HD
>> displays cheat and alternate vertical frames (ie, 1920x1080i showing on a
>> 1080x540(p) display.  You don't loose quality and the switching actually
>> makes the image loko sharper.  But yes, 1920x1080p (1920x1080) HD would
>> be the best video quality, but it is not in the standard.  (SO you know,
>> I plan to buy a 1080p (1920x1080 resolution) DLP projector in 5 years
>> and then de-interlace the 1080i image for "the best" image.  Until then
>> I use a 1024x576 DLP projector)
> 
> 
> Out of curiosity, where did the 1080p discussion come in? I didn't ever 
> mention it, as I haven't even heard of 1080p displays being sold yet (as 
> you said in your other message in this thread).
> 
> So what rez should I be trying to feed from my GF4MX through an Audio 
> Authority VGA->Component converter to a TV that supports 1080i and 480p? 
> I think I tried every single line in your HTPC doc, and nothing worked...
> 
>> All HD display units convert any signal (1080i, 720p, 540p 540i 480p
>> 480i, etc) into the displays native resolution.
>
> 
> Is it the display that does the conversion, or can that be done by the 
> HD receiver? I can actually set my Motorola DCT5100 to output in just 
> about any of the standards, so I thought it was probably the component 
> doing the conversions.
> 
>> As for SD (480i/p) on a HD display it can look terrible.
> 

If you adjust your modeline refresh rates to match the input signal you 
really improve this tremendously.  Turn most of your combfilters and 
deinterlacers in the tv off and you will achieve better results as well.

Everything I have learned about hd signal has come from scouring 
AVSForum and following most of the external links to the items (like 
service modes, modelines, etc.)

> 
> I'll second that.
> 
>> It depends on
>> how the upscaling is being done, and where.  480i tv shows upscaled by
>> the tv stations often is the worst thing I've seen being done.

480i is terrible anyway you look at it.  Matching refresh to exactly 
59.97 and using 1080i is tollerable.

> 
> 
> Yeah, those look pretty crappy when compared to true HD content. Still 
> slightly better than NTSC, but not by much.
> 
>> However,
>> re-recording from film still doesn't get the clarity that exists on the
>> film.  a 4000x3000 stream taken from the original film will start to
>> look as good, but that is 20-30 years off.  (And why people shoudn't
>> wait to see some movies on DVD and should spend the money in the
>> theaters..
> 
> 
> Well, I still like the comfort of my own home, but I see what you mean. 
> :) Sound is another matter though.
> 
>>>> I have only capped streams in Phoenix on ABC and NBC
>>>> and both where the same, however, on NBC... The West Wing still looked
>>>> like crap... Why is one of the highest nielsen numbers shows broadcast
>>>> at
>>>> the worst possible quality (here in Phoenix)
>>>
>>>
>>> Is it possible it is broadcast in an HD format your TV doesn't like?
>>>  From what I understand, a 720p broadcast would have to be scaled by my
>>> tuner to display on my TV (I have a 1080i and 480p capable one; no
>>> 720p)... I'd expect the picture would still be pretty good though. Are
>>> all NBC HD shows that way? Perhaps the NBC affiliate in Phoenix just
>>> doesn't have all the right equipment yet...
>>
>>
>> If your HD display is one of the first, yes, some are dumb and will only
>> take 1 to x signals,  You'll have to buy a tuner that does the scaling
>> in it.  (Sorry)
> 
> 
> Ah, so the tuner does do the scaling in some cases. I believe that is 
> the case with my DCT5100...
> 
>> Most new HD displays accept all/most.
> 
> 
> April 2001 mfg date on mine...
> 
>> Make sure it
>> supports 720p, 1080i, 480i and 480p as a minimum.
> 
> 
> And has an easier way to get video to it from a computer than mine...
> 
>>> I got to watch my first Mariners game broadcast in full-out HD
>>> yesterday. Un-freakin'-believable.
>>
>>
>> :)  That's just your start..
> 
> 
> No doubt. I MIGHT just have to ante up and get HBO and/or Showtime, both 
> of which Comcast is carrying in HD here...
> 
>> ever seen a HD DVD?
> 
> 
> Not yet.
> 
>> X-Men in HD is incredible.  Oh, and as a side note, when you watch 
>> movies on
>> HD/broadcast ATSC, it's over twice as good of quality as that on a dvd.
> 
> 
> Yeah, I've been blown away by how much better the outright HD channels 
> look than DVDs on this same display.
> 
>> It makes it hard to just say, "Oh, I have that on dvd and don't need to
>> wyatch it now:.
> 
> 
> Well, I usually say "I have that on my computer", but... ;p
> 
> I think you have convinced me. I'm going to look into getting HBO and/or 
> Showtime (gotta look a costs a bit...).
> 
> Hey, you wouldn't happen to know why my pcHDTV card that was supposed to 
> ship in 2 days when I ordered it a week and a half ago hasn't shown up 
> yet, would you? :)
> 
> --Jarod
> 
> 
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