Image Quality from HTPC

Forums › Home Theatre (including HTPC and EPG Collector) › Image Quality from HTPC

madad

75 posts

Master Geek

#60635 29-Apr-2010 12:36

Hi there, just a general question here regarding the quality of image coming from an HTPC:

I've hooked up the UHF feed to my shiny new plasma and the quality of the tv image from the tuner in the tellie is stunning.

I'm concerned that the quality of the image coming from my HTPC is not up to scratch. I'm still running a standard def signal into the tuners in the pc (yet to get a string enuf signal to push the DVB-T cards) but I'm not very comfortable with the fact that the computer is processing the signal before it goes out of the onboard HDMI connection to the TV.

If I'm playing a 1080p mkv from my htpc should I expect great quality, or should I consider a high quality graphics card for the pc? (I'm using onboard which according to the manufacturer is rated for full 1080p output via HDMI)

Hope that all makes sense..

Cheers!

elkano

160 posts

Master Geek

#324696 29-Apr-2010 13:33

madad:

If I'm playing a 1080p mkv from my htpc should I expect great quality, or should I consider a high quality graphics card for the pc? (I'm using onboard which according to the manufacturer is rated for full 1080p output via HDMI)

Hope that all makes sense..

Cheers!

Hi madad.
I've used DVB-T freeview through the computer and I can tell you it looked very nice indeed. Unfortunately I don't have a TV with an onboard Freeview decoder so I can't give you my impressions there.
I would expect most native TV decoders to do a decent job.

Can you post your system spec's so we have an idea about what hardware you're using?
Most of the new motherboard HDMI outputs do a good job with 1080P material, but interlaced (1080i like DVB-T freeview TV3) material can be a different story. Depending on what deinterlacing options are hardware assisted by your system you may see a difference.

Cheers

el_kano

Samsung

Shop now on Samsung phones, tablets, TVs and more (affiliate link).

Ragnor

8192 posts

Uber Geek

Trusted

#324700 29-Apr-2010 13:38

What make/model are the TV and onboard video on the htpc motherboard?

These sample clips / trailers might be useful to you for testing
http://www.h264info.com/clips.html

madad

75 posts

Master Geek

#326421 4-May-2010 12:36

Right, some specs..

The tv is a panansonic 50" plasma. I'm using onboard ATI HD3200 HDMI output to the tv. The HTPC is windwos 7 x86.

I'm really struggling with the black levels, everything seems to drop off to black very quickly and I feel like in a dark scene I can't see any detail. The problem is common to tv (freeview) as well as sources such as Bluray from the htpc. The whole picture tends to looked washed out.

I'm upgrading to version 10.4 of the catalyst drivers to see if that helps, I see there's a few people complaining about such issues on the net.

I played with the gamma setting last night which reduced the greyness of the picture, but also resulted in less detail in dark scenes.

Should I switch back to an Nvidia card perhaps?

Deev8

481 posts

Ultimate Geek

#326518 4-May-2010 15:39

madad: I'm really struggling with the black levels, everything seems to drop off to black very quickly and I feel like in a dark scene I can't see any detail. The problem is common to tv (freeview) as well as sources such as Bluray from the htpc. The whole picture tends to looked washed out.

Does live broadcast TV look much better?

richms

27955 posts

Uber Geek

Trusted

Lifetime subscriber

#326583 4-May-2010 19:01

blacklevels are a pain to deal with on a PC going to a TV since you either stretch it causing bad banding, or dont stretch it and hope that the tv will not show 16 as grey like most seem to.

adjusting the brightness/contrast controls was enough to get my sisters tv showing 16 as black, and there was no banding either like when the mpeg4 codec was doing it on the PC. Desktop etc looks pretty bad with the brightness and contrast set like that, but that is secondary to having black show as black.

Richard rich.ms

madad

75 posts

Master Geek

#326750 5-May-2010 09:39

Well interestingly (and after many hours of research - seems I'm not the only one struggling with this issue) I upgraded to the latest ATI drivers (10.4) yesterday and it made a huge difference to the quality of the picture. It's a lot darker but now seems to be accurate - the grey washed out look is gone. And that's for live tv as well as bluray content.

The picture is certainly darker than I'd like, so I'll continue to tweak brigh5tness and contrast but so long as I dont end up with the horrible greyed out mess I had before I'm happy..

madad

75 posts

Master Geek

#329669 13-May-2010 10:10

After watching a mate's Bluray player playing Avatar on the same panel as I have last night I have decided that perhaps a media pc is not a good way to go.

I am completely unable to get the TV to recognise a 24p signal from my htpc. Is there something I have to do to get that to work? I thought manually setting the display settings to 1080p 24hz would have done the trick? But I get none of the 24p options in the TV menu..

RustyGonad

495 posts

Ultimate Geek

Trusted

#329697 13-May-2010 11:07

The 3200's use shared onboard memory... This is slow...

There's a big difference in being able to display Bluray and tick the marketing boxes, and be able to display it well... All of the onboard's I have seen manage to tick the marketing boxes very well... When it comes to real performance they all seem to suck... that includes the 3200's (I turned my one into a WHS box, because it sucked so bad) and the 8200/8300's from NVidia. Sharing memory is cheap, but it isn't fast...

It could be that you've just found the limit of your onboard display chipset. It either can't display a 24p signal correctly, or its just running out of bandwidth to display a high bitrare Bluray such as Avatar.

There are certainly plently of graphics cards out there that can do a more than adequate job of displaying 1080p Bluray sources correctly, both from ATI and NVidia.

elkano

160 posts

Master Geek

#329707 13-May-2010 11:18

madad: After watching a mate's Bluray player playing Avatar on the same panel as I have last night I have decided that perhaps a media pc is not a good way to go.

I am completely unable to get the TV to recognise a 24p signal from my htpc. Is there something I have to do to get that to work? I thought manually setting the display settings to 1080p 24hz would have done the trick? But I get none of the 24p options in the TV menu..

I know previously (pre 2010) that to get 24P (which is actually 23.975) you had to use 23HZ and possibly reclock to sync. People have had it working correctly with 780g and 3200, but I'm not sure if there have been changes with the new drivers.

Check out this discussion:

http://www.avforums.com/forums/home-entertainment-pcs/1125692-does-ati-do-24p.html

1gkar

722 posts

Ultimate Geek

#329887 13-May-2010 17:59

madad: After watching a mate's Bluray player playing Avatar on the same panel as I have last night I have decided that perhaps a media pc is not a good way to go.

I am completely unable to get the TV to recognise a 24p signal from my htpc. Is there something I have to do to get that to work? I thought manually setting the display settings to 1080p 24hz would have done the trick? But I get none of the 24p options in the TV menu..

Seeing as how you don't state what your HTPC config is, I can't assist that much.

However, if you are looking at Reclock as a means of avoiding video stutter, look at this for a good beginning. If you are using MediaPortal, in the last area of 'MPConfig>General' there is a section titled Dynamic Refresh Changer (I think). If you enable this it will automatically change the refresh rate, & you can enable a notifier which shows what the vieo is being refreshed to.

I was unsure if this was good for my LCDTV @24p resolutions, however the good folks here have assured me that in modern digital TVs, if your TV can handle the resolution, it will display it. Here is the thread if you're interested. If my TV craps out, they will be getting the bill

Silverstone LC14 HTPC Case/Intel E4600 CPU/GA-EP35-DS3 MOBO/Asus EN9500GT graphics/2GB RAM/total 2TB HDD space/HVR-2200 & 2X 150MCE tuner cards/LG GGC-H20L BD Drive/MCE2005/Mediaportal/TVServer 1.1.0Final/LG 55"3D LED-TV/Denon AVR-1803 receiver/X1 projector

madad

75 posts

Master Geek

#330055 14-May-2010 11:25

Sorry I was light on details regarding the platform I'm using - I have an AMD Quad core running on a Gigabyte GA MA78GM S2H. I was using the onboard hdmi but have gone out this morning and purchased an XFX Geforce 240 in the hopes that I will get a better picture. Its not so much stuttering I'm trying to avoid - its more image clarity, colour balance and smoothness of motion. I was under the impression the TV supports 24p but I can never find it in the TV's menu, even when I'm running the pc at 24hz. So I'm a little confused.

elkano

160 posts

Master Geek

#330058 14-May-2010 11:35

What is the exact model of the TV? I imagine the TV will automatically adjust based on the input, but need to know model to check for sure.

richms

27955 posts

Uber Geek

Trusted

Lifetime subscriber

#330185 14-May-2010 16:38

When I have tried 24Hz on a PC it was VERY obvious on the mouse update rate being so low as being almost unusable. That should give you an indication if you have 24Hz or not.

Richard rich.ms

1gkar

722 posts

Ultimate Geek

#330200 14-May-2010 18:03

I recommend you run Monitor Asset Manager. Install this & it will give you your TV's capabilities; maybe. I ran it for my 32"Samsung & it stated the screen size was 7.25". But others seem to have no issues with it. Try it & see what vertical refresh rates your TV is capable of. I got the app from here.