View unanswered posts    View active topics

All times are UTC - 6 hours





Post new topic Reply to topic  [ 21 posts ] 
Go to page 1, 2  Next

Print view Previous topic   Next topic  
Author Message
Search for:
PostPosted: Mon Feb 05, 2007 9:38 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
This is where I'm a bit confused.

If I use MythTV to connect (via DVI on the Nvidia card) to the HDMI input on the TV (via a DVI to HDMI converter), to a Widescreen Toshiba Plasma, do I need to manually adjust the modelines?

If so, is there no way to get MythTV to do an "auto" or passthrough for the format?

Meaning, SOME of our stations are 720p and some are 1080i. With my cable box or direct QAM tuning on the TV itself, it will "sense" the native resolution of the signal (going QAM to the TV) or I can enable "pass through" on the cable box (rather than making the cable box use its crappy internal scaler to 1080i for everything). The reason I ask is that most of the action shows are 720p (I think that's what CBS and FOX use?) But I think ABC uses 1080i where I'm at.

I've gotten the VGA output to work okay by using the remote to cycle to 16:9 but it doesn't fill the whole screen (and I don't mean the black bars, I mean it's like it thinks it's a 32" TV instead of a 42" or something). My guess is that I have to adjust the output resolution to "fill" the screen.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Feb 05, 2007 10:22 pm 
Offline
Joined: Wed Feb 08, 2006 6:13 pm
Posts: 480
Location: IN
You will need to determine what the native resulution for your plasma TV is (check your manual or look for your model number online). You will then want to generate a modline to output that resulution to your TV. There is plenty of information on the internet about generating mode lines so I'm not going to go into that here.

It is always best to output the native resulution to a plasma or LCD TV otherwise you will get aliasing. Besides a computer will almost always do a far better job of scaling than any settop box or TV! Just use the 'w' key in Myth to change aspect ratios if you need to.

Sorry for being a little lite on details but I hope this can point you in the right direction.

Best of luck,

Martian

_________________
ABIT NF-M2 nView | Athlon 64 X2 3800+ | 2GB DDR2 800 | HDHomerun | GeForce 6150 (onboard) | WD 640 GB SATA HD | DVD-RW (sata) | StreamZap IR receiver with Logitech Harmony remote

Vizio 37" LCD HDTV (1080p)


Top
 Profile  
 
PostPosted: Tue Feb 06, 2007 6:35 am 
Offline
Joined: Fri Apr 02, 2004 10:08 am
Posts: 1637
Location: Virginia, USA
hurnik wrote:
The reason I ask is that most of the action shows are 720p (I think that's what CBS and FOX use?) But I think ABC uses 1080i where I'm at.


I am pretty sure that ABC and FOX are 720p and CBS is 1080i nationwide. I don't believe that local affiliates have the ability or the permission to convert that signal.

http://en.wikipedia.org/wiki/High-defin ... iderations

(check last paragraph for listing of channels and what they're broadcasting)


Top
 Profile  
 
 Post subject:
PostPosted: Tue Feb 06, 2007 8:34 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Martian wrote:
You will need to determine what the native resulution for your plasma TV is (check your manual or look for your model number online). You will then want to generate a modline to output that resulution to your TV. There is plenty of information on the internet about generating mode lines so I'm not going to go into that here.

It is always best to output the native resulution to a plasma or LCD TV otherwise you will get aliasing. Besides a computer will almost always do a far better job of scaling than any settop box or TV! Just use the 'w' key in Myth to change aspect ratios if you need to.

Sorry for being a little lite on details but I hope this can point you in the right direction.

Best of luck,

Martian


that's okay. I'm fairly "comfortable" with the modeline settings.

i was more curious as to whether MythTV would auto-adjust the resolution based upon the input on the QAM stream. (ie, if it's getting passed 480i, does it "auto" switch to 480i and then when it detects a 720p does it auto-switch)?

Or am I forced to do this manually or forced to up-convert everything?


Top
 Profile  
 
PostPosted: Tue Feb 06, 2007 8:36 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
ceenvee703 wrote:
hurnik wrote:
The reason I ask is that most of the action shows are 720p (I think that's what CBS and FOX use?) But I think ABC uses 1080i where I'm at.


I am pretty sure that ABC and FOX are 720p and CBS is 1080i nationwide. I don't believe that local affiliates have the ability or the permission to convert that signal.

http://en.wikipedia.org/wiki/High-defin ... iderations

(check last paragraph for listing of channels and what they're broadcasting)


Yes, now thatyou mention it, that is correct. But again, does Myth auto sense and adjust accordingly? Or do you have to hard-set it to whatever you want it to be? By default my SA 8300 HD DVR from Time Warner is set to up-convert everything to 1080i (and it does a sucky job). I enabled pass thru and let the TV do the converting for me and it works much better. But I don't know (nor could I find anywhere) if MythTV has the ability to sense the incoming signal and output accordingly (not even sure if this is software or totally dependant upon the DVB tuner card?)


Top
 Profile  
 
 Post subject:
PostPosted: Tue Feb 06, 2007 9:18 pm 
Offline
Joined: Wed Feb 08, 2006 6:13 pm
Posts: 480
Location: IN
I guess I wasn't as clear as I could have been. MythTV will automatically scale / convert everything to the resolution you define with your modeline. For example in my case since my LCD panel is 1366x768 native Myth converts everything to 1366x768 (it's actually 1368x768 for technical reasons). No matter what the source be it analog, 480i, 480p (DVD), 720p, 1080i it all gets sent to my panel at 1368x768. This is a very good thing as computer hardware does an excellent job of scaling. I think you will find that your Myth box does a better job of scaling than your set-top box or your TV.

I hope I did a good job of explaining it this time.

Martian

_________________
ABIT NF-M2 nView | Athlon 64 X2 3800+ | 2GB DDR2 800 | HDHomerun | GeForce 6150 (onboard) | WD 640 GB SATA HD | DVD-RW (sata) | StreamZap IR receiver with Logitech Harmony remote

Vizio 37" LCD HDTV (1080p)


Top
 Profile  
 
 Post subject:
PostPosted: Tue Feb 06, 2007 9:33 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Okay, so I think I'm understanding now.

So as long as you DEFINE the modeline (ie, 720p) you can pretty much specify whatever resolution you need it to be.

Gotcha. Makes sense.

I just wasn't sure if it "saw" the signal coming in (you don't get a detailed manual with the DVB card).

Sounds great, thank you VERY much for the help. Now I'm off to blow up my TV (haha).

Can you believe how much they charge for a DVI to HDMI cable? Good grief, like $100.00


Top
 Profile  
 
 Post subject:
PostPosted: Wed Feb 07, 2007 5:37 am 
Offline
Joined: Fri Apr 02, 2004 10:08 am
Posts: 1637
Location: Virginia, USA
hurnik wrote:
Can you believe how much they charge for a DVI to HDMI cable? Good grief, like $100.00


Go to monoprice.com instead, they have DVI to HDMI adapters or cables for under $10. I found out about them on the HDTV podcast.

Also, on your original topic, there are ways of having MythTV change resolutions depending on what it is playing back, so you could get it to drop to 480 for SD shows, then to 720 or 1080 depending on the HD recording. I've never wanted to mess with it though, because as Martian said, the computer does an excellent job of scaling up or down to your output resolution.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Feb 07, 2007 12:34 pm 
Offline
Joined: Wed Feb 08, 2006 6:13 pm
Posts: 480
Location: IN
ceenvee703 is correct that there are ways of having MythTV or really Xorg change output resolutions, and with a CRT based TV there are situation where that could even be beneficial however with an LCD or Plasma (as in the case of this thread) there is absolutely no reason to output anything other than the native resolution of the display!

Martian

_________________
ABIT NF-M2 nView | Athlon 64 X2 3800+ | 2GB DDR2 800 | HDHomerun | GeForce 6150 (onboard) | WD 640 GB SATA HD | DVD-RW (sata) | StreamZap IR receiver with Logitech Harmony remote

Vizio 37" LCD HDTV (1080p)


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 11:18 am 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Well, went through the manual and it says nothing about native resolutions anywhere.

The ONLY time it mentions resolutions is if you use the "pc" input (ie: VGA). for HDMI it only mentions 480i, 480p, 720p, 1080i

Toshiba 42HP95

I guess I'll have to google and see if I get lucky.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 11:38 am 
Offline
Joined: Fri Apr 02, 2004 10:08 am
Posts: 1637
Location: Virginia, USA
hurnik wrote:
Toshiba 42HP95


I googled it and it appears to be a 720p plasma screen, which usually means native resolution is 1024x768 (particularly in the 42" screen size).

Yup, here's the Toshiba page, the spec sheet says 1024x768

http://www.tacp.toshiba.com/televisions ... del=42hp95


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 12:08 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Thanks, that's what I found too. Although there seems to be on the AVS Forums that it's actually 1366x768, so I guess I'll try the 1024x768 first.

Can I ask a dumb followup?

If the native resolution is 1024x768, and Myth (actually the Nvidia drivers in xorg) show that it's "doing" 1024x768, is there a special option to get it to fill the entire screen?

Currently (playing around with the "W" key), I can get it to do 16:9 for HDTV, and while it shows "letterboxed" it's not filling the entire screen. And I don't mean the black bars on the top/bottom. There's like a 4" black border around the entire video (almost like it thinks I've got a smaller TV or something).

Now, this could be due to the fact I'm using the VGA input on the TV currently (waiting for my DVI to HDMI cable to arrive), but I don't know for sure.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 3:21 pm 
Offline
Joined: Fri Apr 02, 2004 10:08 am
Posts: 1637
Location: Virginia, USA
I wish I had a plasma, hopefully someone here who does, and whose runs at 1024x768, can answer more knowledgably.

There is a setting that should be in your x.org called DisplaySize. That is where you'd specify the dimensions of your monitor. Even though the 1024x768 resolution is a 4:3 aspect ratio with square pixels (like a computer monitor), by configuring DisplaySize with the measurements of your monitor, you'll tell X that your monitor is actually 16:9 and that the pixels should be rectangular, not square.

http://xinehq.de/index.php/faq#ASPECTRATIO


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 3:40 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Thanks! That points me in the right spot to look at.

(wow, in millimeters??)


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 11, 2007 4:14 pm 
Offline
Joined: Wed Dec 27, 2006 4:13 pm
Posts: 116
Well, I guess I must be doing something wrong (or it just plain doesn't work in the VGA port of the TV).

I've set it to DisplaySize 1100 778 (which according to the manual is the physical size in mm)

no difference.

I get 16:9 on HD content, just that it's got nice 4-5" black bars all around it.

The modeline section of xorg.conf is VERY long.

But I'll keep playing (it may just be that the VGA connector cannot do 'widescreen' or anything to fill the entire screen) on the TV.


Top
 Profile  
 

Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 21 posts ] 
Go to page 1, 2  Next



All times are UTC - 6 hours




Who is online

Users browsing this forum: Bing [Bot], Seo-Ul-Nah and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group

Theme Created By ceyhansuyu