Flickering when watching TV

[Sven]

MediaPortal Version: 0.2.2.0
MediaPortal Skin: BlueTwo
Windows Version: Vista Ultimate 32 Bit
CPU Type: Athlon X2 4200+
HDD: 2 * 250 GB
Memory: 2 GB DDR2 RAM
Motherboard: ASUS M2N-SLI Deluxe
Motherboard Chipset: nVidia 570 SLI
Motherboard Bios: 609
Video Card: ASUS EN7600 Silent (Geforce 7600GT)
Video Card Driver: ForceWare 158.24
Sound Card: SoundMax HD Audio (onboard)
Sound Card Driver: AnalogDevices, version 6.10.1.6110
1. TV Card: Hauppauge HVR-1300
1. TV Card Type: hybrid (DVB-T, analogue)
1. TV Card Driver: CD version 3.4a
MPEG2 Video Codec: DScaler Codec
MPEG2 Audio Codec: MPA Decoder Filter
Power Supply: 430W


Hi,

I have the following problem when using MediaPortal (which is, apart from this, really comfortable - thanks!):

After some time of watching TV the live TV playback begins to flicker, i.e. the screen alternates between the video and a black screen. Usually, this only concerns part of the picture, sometimes just about the upper third, sometimes almost the whole picture flickers. Mostly, it gets worse when I continue to watch TV anyway. Opening a window, such as the mini-EPG (press return), usually causes less of the picture to flicker as long as it stays open.

The black flicker is not rectangular but the bottom end (it always begins at the top most of the screen) looks somewhat "frayed" (in case this is important).

Usually this occurs after some time of watching but changing channels frequently seems to limit the time the picture is OK even more (I have the impression that the (original) aspect ratio of the TV video or the change of this also plays a role).

The same problem also occurs when watching video files (DivX) but I have only noticed it when pausing the video (so far).

I have attached the log of a "session" in which this problem occurs.


Thanks in advance,
Sven

[edit]Fixed typo in subject[/edit]

[Sven]

Hello,

now the problem also occurs sometimes while watching TV (without changing any channels) and disappears after some seconds/minutes. Usually this only concerns the upper part of the video. But eventually, the whole screen flickers without recovering on its own.

As a picture says more than a thousand words, I have attached a photo showing the effect. Maybe this could help. The height of the black area changes all the time and as I said above, it quickly alternates with the TV playback.
(The picture is only blurred because the scene happens to be a dream.)

While searching for a solution, I found MediaPortal bug 885 in Mantis. I'm not sure whether it describes my problem but I tried version 0.2.3.0 RC1 some days ago anyway and the problem still exists.

What else can I do to solve the problem?

Sven

[tourettes]

Have you tried enabling directx exclusive mode (config - vmr9) ?

[Sven]

Thanks for your help!

Originally Posted by tourettes

Have you tried enabling directx exclusive mode (config - vmr9) ?

Yes, i have just enabled "Use Exclusive DirectX mode - avoids tearing" but unfortunately, this does not really help. There is a difference, though: Up to now the TV playback has not yet flickered but now the windows (such as the mini-EPG) flicker instead (quickly alternating menu and TV playback, no black screen).

There is no option concerning VMR9, though (maybe this is because I reverted to MP 0.2.2.0 stable for the moment).

Any other suggestions?

Regards,
Sven

[Paranoid Delusion]

Try setting up MP as a profile in Nvidia advanced settings, and set the antialiasing to a different value (try them all).

It does sound more of a Graphics Card\driver problem.

VMR exclusive is in 0.2.2.0, under General settings.

[Sven]

I tried all available options for antialiasing but, unfortunately, this did not help.

By the way: Prior to installing ForceWare 158.24, I tested with the built-in Vista driver (same problem there). So if the driver is the culprit, both drivers must have this problem. Besides, I have not noticed the problem in any other TV/video software I tried (e.g. Windows Media Player and Windows Media Center).

Originally Posted by Paranoid Delusion

VMR exclusive is in 0.2.2.0, under General settings.

Is this the same as "Use Exclusive DirectX mode - avoids tearing"? Otherwise I must be blind, I cannot find "VMR" anywhere under "General settings."

[Sven]

Please, is there anything else I can try to solve the problem?

I have now (for the first time) noticed another strange issue: When watching TV, the video is cut off on the top and bottom side (about 5cm are missing on each side) This problem (in contrast to my first problem, which is still there, too) cannot be solved temporarily by restarting MP/rebooting.
It is a "clear" cut, if I didn't know there's something missing (e.g. when they show some text on TV), I couldn't tell by just seeing the picture.

I don't remember changing any setting concerning this. Is there an option I have to correct or is this an unknown issue? I'm not using the TV-out of my graphics card but my usual TFT monitor for watching TV (so it's not just the overscan of a TV monitor).


Concerning the flickering: I continued my search and found some posts mentioning log entries such as the following (my log file contains them as well):

2007-07-17 12:30:24.839596 [Info.][MPMain]: VMR9Helper: playing->repaint 50

Maybe this has something to do with my problem. If this is so, what can I do?

One more question: Does Bug 885: TV playback has strobe effect when viewing describe my problem (I'm not sure)?


Thanks,
Sven

[Sven]

Having googled furthermore, I suspected my dual-core processor (I did not find anything specific to my flickering problem though). But I found out the flickering is independent from that (I limited Windows to one core for testing - the problem remains).

Every time I checked, after the flickering there were several log entries such as the following (see my previous post):

2007-07-17 12:30:24.839596 [Info.][MPMain]: VMR9Helper: playing->repaint 50

What does this log entry mean?

I'd also like to know whether it works for other people with the same setup (mainly a Geforce 7600GT and Vista).


Thanks,
Sven

[Sven]

Hi,

yesterday, I finally found a solution for this problem while playing around with the new 0.2.3 RC2. In case someone else suffers from strange flickering, here is what works for me:

Enabled the Enhanced Video Renderer (EVR) seems to fix the strange flickering issue. Up to now, I could not reproduce it
(When using VMR, the problem still exists, though. But EVR seems to work quite well, so this is no problem for me.)


Sven

[kkendall]

...Hi Sven, If I read your post earlier, I could have told you enabling EVR is kind of a solution (...sorry for not noticing your post.) but sertainly not the final solution...unfortunately.

The main thing with EVR on is that MediaPortal randomly freezes up when watching recordings... The only thing you can do at that point is to restart MP.

So EVR improves videoquality (without EVR black colors aren't black anymore...And everything is less, ...say sparkling) and doesn't give flickering/flashing screens anymore but crashes MP when watching recordings and tv (this doesn't happen when watching videos).

There is a Vista EVR supportproblems thread on this forum to see the progress on this issue...