Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.


View this topic in a long page with up to 500 replies per page Create new topic
1 | 2 


360 posts

Ultimate Geek
+1 received by user: 3


  Reply # 148135 15-Jul-2008 15:34
Send private message

the screen shot for FFDshow looks like lots of options are made available to the user, hopefuly one of them will help...

which one do you use? http://sourceforge.net/project/showfiles.php?group_id=53761
there are two separate dowloads available, one around 350K and the other over 2Mb...




mobo Intel DH55PJ, RAM: 4GB RAM, Nova-T 500 HD + Avermedia Trinity tuner card, Geforce 520 video, 120GB SSD Sandisk + 640 WD + 1000SG, Win7 Home Prem 64-bit, Media Portal 1.15.0; BTC 9019URF Cordless Keyboard, Panasonic 55" (HDMI cable), HTPC Case Silverstone Grandia GD05B.


222 posts

Master Geek
+1 received by user: 11


  Reply # 148236 15-Jul-2008 18:54
Send private message

Codecs are about compression and decoding, not video levels.

Look in the ATI video setup, I don't have access right now to my box, but look for "video levels".
I suspect you are outputing PC levels, not video levels.

To be clear, outputting at video levels(16~235) does not mean you are missing anything.
Currrently all western countries use video levels(16~235), except for Japan who use 1~254(the basis for xvColour).
It is a legacy thing from TV's early days when they had trouble transmitting levels accurately and so created head and foot room to make sure the whole signal was transmited.

It may be dropped one day, for now always use video levels.

xvColour, simply don't bother using it, although mostly acepted by the industry the change is not so easy as the whole industry is entrenched in the current system.

Too round up,
PC = 0~255
Video=16~235
xvcolour= 1~254 (only used by Japan)

You don't mention what display you are using?
High contrast levels, using vivid or so called super bright settings usually clip the top end.




Masterpiece Calibration Ltd, isf certified

 

www.mastercal.co.nz

 

 

"I'm not a robot!"

 
 
 
 


20279 posts

Uber Geek
+1 received by user: 3832

Trusted
Subscriber

  Reply # 148237 15-Jul-2008 18:58
Send private message

coreavc has an option to make it output the full 255 levels, without it the background and encoded letterbox bars are clearly grey when viewed on a PC. I have seen black level options in some other codec installed too.




Richard rich.ms

222 posts

Master Geek
+1 received by user: 11


  Reply # 148243 15-Jul-2008 19:16
Send private message

Viewing 16~235 material expanded to 0~255 only creates artifacts.

You should change the video card to display video levels.



The major one is a banding issue where you can see stages in a grey ramp, which is the basis of video with colour added.



One must be careful not to create a push pull effect by setting up things to expand and contract, you could cause clipping of the signal at either end.







Masterpiece Calibration Ltd, isf certified

 

www.mastercal.co.nz

 

 

"I'm not a robot!"



360 posts

Ultimate Geek
+1 received by user: 3


  Reply # 149748 21-Jul-2008 08:39
Send private message

Guys!
I think we are on the right track, some of the symptoms described here really apply to my system's behaviour!!

Quote: "Viewing 16~235 material expanded to 0~255 only creates artifacts."
Well, this is one of the issues bothering me the most, I never understood why the 720p signal (or the TV3 1080i) played on a 46" 1366x768 screen has to show sooooo many artifacts, no matter what codec I use !! This might be it! The video levels all of you told me about.

I have ffdshow installed and I looked through it but honestly, there are so many options there that I (nearly) got lost so I did not change anything for the moment.

Do I need to activate ffdshow at every start-up somehow, or you just launch the configuration screen, do the adjustments, close it and from now on, every codec you use will get the settings from there? Do I need a reboot after any adjustment made in ffdshow (does it make changes in the registries)?

Maybe the following will also confirm what you have been saying so far:
- when watching 4:3 signal from aerial or other source connected to the Tv, the black pillars are really black and the "boundaries" where the image starts and stops are very clearly defined (one pixel is on and the next one is completely off, nice perfect vertical lines both sides). No random contrast changes.

- when playing back HD (or not) material on my pc (BUT NOT RECORDED TV !!!)and the image is not exactly 14:9, the black bars (top/bottom or on the sides) are same as before, deep black and very well defined. No random contrast changes. Could be the video levels again, in the right range when playing hd clips from inside Media Portal ??

- LIVE TV: first of all, the contrast change is very annoying, we talked about this (it applies to the whole screen, including the black pillars if they exist). When the image is not "wide screen", the black pillars on the sides are not really black, and they are VERY blocky. The "boundary" betwen image and "pillars" is not very sharp and well defined anymore, looking closely I see the pixels "blending in", approx 2 pixels each side, making the vertical "separation line" more like a strip. Plus all the blocky artifacts inside the black bars and some other vertical lines inside the black bars, fairly light grey, running from top to bottom of the screen. They are visible when watching from fairly close (1-1.5m), I usually watch from 5m away.

I had the tv tuner replaced so far, and phoned Sony several times asking how to turn the dynamic contrast off for the PC inputs but they said they do not know how it can be done as it is not in the Manual !! Thank you for that, Sony, I have the manual myself and I think I read it before asking for help...

I identified an ".inf" file in the nVidia installation directory which contains a line something like "...DynamicContrast = 0x40000000", and I edited that value to 0x00000000 but this did not help (not sure right now about the number of zeroes, all I did was to change the "4" with a "0"). Maybe the file was used to create registry entries during installation and is not used after that. I searched for a registry entry to contain the words/entries/keys "dynamic" or "contrast" but I could not find any... A reboot did not bring any changes to the system. Maybe I should re-install after modifying the ".inf" file...


WHAT I JUST FOUND: http://www.avsforum.com/avs-vb/showthread.php?t=1049346  - DO YOU THINK THIS WILL SORT IT OUT FOR ME???? I WILL SEE LATER TODAY ........  BUT THE FEEDBACK FROM USERS IS REALLY GOOD !!!!!!!!!




mobo Intel DH55PJ, RAM: 4GB RAM, Nova-T 500 HD + Avermedia Trinity tuner card, Geforce 520 video, 120GB SSD Sandisk + 640 WD + 1000SG, Win7 Home Prem 64-bit, Media Portal 1.15.0; BTC 9019URF Cordless Keyboard, Panasonic 55" (HDMI cable), HTPC Case Silverstone Grandia GD05B.




360 posts

Ultimate Geek
+1 received by user: 3


  Reply # 156450 12-Aug-2008 22:52
Send private message

It is all sorted out.
A clean install solves any problem... good old "clean install"... I had no idea my TV set can deliver such nice picture... and there are no artifacts at all on TV1, 2 and 3.

Thank you all for the help and sharing your knowledge.
I will not continue this post.




mobo Intel DH55PJ, RAM: 4GB RAM, Nova-T 500 HD + Avermedia Trinity tuner card, Geforce 520 video, 120GB SSD Sandisk + 640 WD + 1000SG, Win7 Home Prem 64-bit, Media Portal 1.15.0; BTC 9019URF Cordless Keyboard, Panasonic 55" (HDMI cable), HTPC Case Silverstone Grandia GD05B.


1 | 2 
View this topic in a long page with up to 500 replies per page Create new topic



Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:



Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:



Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:





News »

Vocus New Zealand on the block as Aussies bail
Posted 23-Oct-2017 17:06


Vodafone TV — television in the cloud
Posted 17-Oct-2017 19:29


Nokia 8 review: Classy midrange pure Android phone
Posted 16-Oct-2017 07:27


Why carriers might want to embrace Commerce Commission study, MVNOs
Posted 13-Oct-2017 09:42


Fitbit launches Ionic, its health and fitness smartwatch
Posted 12-Oct-2017 15:52


Xero launches machine learning automation to improve coding accuracy for small businesses
Posted 12-Oct-2017 15:45


Bank of New Zealand uses Intel AI to detect financial crime
Posted 12-Oct-2017 15:39


Sony launches Xperia XZ1, a smartphone with real-time 3D capture
Posted 11-Oct-2017 10:26


Notes on Nokia’s phone comeback
Posted 10-Oct-2017 10:06


Air New Zealand begins Inflight Wi-Fi rollout
Posted 9-Oct-2017 20:16


The latest mobile phones in perspective
Posted 9-Oct-2017 18:34


Review: Acronis True Image 2018 — serious backup
Posted 8-Oct-2017 11:22


Lenovo launches ThinkPad Anniversary Edition 25
Posted 7-Oct-2017 23:16


Less fone, more tech as Vodafone gets brand make-over
Posted 6-Oct-2017 08:16


API Talent Achieves AWS MSP Partner Status
Posted 5-Oct-2017 21:20



Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.



Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.