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Discussion Starter #1
One issue that I have experienced with CTV over the past couple of weeks is that there is a flickering on any film-like content. Regular 60Hz video is fine, however if a film clip is shown, the screen starts to flicker. So shows like "Big Bang Theory" and "Hot in Cleveland" are affected, but not, say, Dr. Oz. I'm using WMC 7 and recording using a HVR-2250. I have also tried playing the recordings on another HTPC with the same results. Also, similar film-like content recorded from other OTA stations displays normally with no flickering. Any ideas?
Cheers!
 

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I have the same problem with Win 7 MC as well. Just so you know Vista MC works fine, so does my TV Tuner. It's a Win 7 MC problem. As to what the answer is? Who Knows? All I can say is MC is like that sexy girlfriend that constantly needs maintenence.:rolleyes:
 

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Discussion Starter #3
The odd thing is that it has been working perfectly for months with no issues - then flickering. Very strange...
 

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Could it have to do with interlaced content? Some content is 720p, some is 1080i and I noticed some driver issues with ATI and Windows 7 that caused the display to completely stutter on any interlaced content.

Pete
 

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Could it have to do with interlaced content? Some content is 720p, some is 1080i and I noticed some driver issues with ATI and Windows 7 that caused the display to completely stutter on any interlaced content.

Pete
Well I do have an ATI card (5770) but.....
a:It only happens on CTV
b:It doesn't happen on Vista MC
c:The machine is dual boot
Mystery to me
 

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definitly sounds like a driver issue in windows 7. maybe try a newer/older driver. and see if it fixes it.
Well there is no newer driver and I'm not going to sacrifice performance in other apps for this one.
To be honest this HTPC experiment is just a pain IMHO.
 

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Lots of background info here. I suspect the driver is failing one of these tests due to a change by the broadcaster. I.E. Incorrect re-encoding.

http://www.hometheaterhifi.com/volu...uide-to-progressive-scan-shootout-1-2003.html

Test Name: 3-2 Cadence, Mixed Flags
What it Measures: Can the deinterlacer go into film mode and stay there, with NTSC film-source material which is changing back and forth from standard film-style flags to video-style flags.

Test Name: 3-2 Cadence, Video Flags
What it Measures: Can the deinterlacer go into film mode and stay there, with NTSC film-source material that was authored without any inverse telecine, and with no frame marked progressive (i.e., flagged as video).

Test Name: 3-2 Cadence, Alt. Flags
What it Measures: Can the deinterlacer go into film mode and stay there, with NTSC film-source material that was authored using an encoder that turns the progressive flag off every other frame.

Test Name: 3-2 Cadence, Film Flags
What it Measures: Can the deinterlacer go into film mode and stay there, with standard NTSC film-sourced material.
 

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I have an Nvidia 8500GT in my HTPC and the picture is stunning with no flickering. It does a better job in the 1080p conversion than my TV does (I can see shimmering caused by de-interlacing on my TV's tuner when watching live sports).

If you have an ATI card, you may want to consider updating the drivers or as a last resort, pick up a Geforce 210 (~$30-40).
 

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Discussion Starter #11 (Edited)
Thanks for all the comments. I emailed CTV Vancouver to inform them of what I was experiencing and I received the following message:

"A possible reason for the change on your DVR is that we are sending variable bit rate instead of constant bit rate. Variable bit rate will use less space on your DVR as the bit rate will change depending on the movement in the picture and how complex each scene is. Constant bit rate is always the same and can include "empty data" (null packets) to keep the data rate at the highest rate and therefore can require more hard drive space."

I did notice that in the past couple of weeks the recording size of the shows I mentioned in the first post are significantly smaller in size than before, when I had no problems with the flickering.

I was able to minimize the flickering by unchecking the "Enable Dynamic Contrast" in the catalyst drivers, however, the accompanying stuttering remains - the video seems to jump ahead intermittently with artifacts. I am using an ATI HD 5570 graphics card with Catalyst 10.7 drivers.
 

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You may want to reset all the CCC settings back to default. Also, uninstall any codec packs you may have added. I would also download Win7DSFilterTweaker (use google). It will let you check which Directshow codec has priority. In your case, you will want to look at MPEG-2 and make certain it is set to Microsoft. Good luck!
 

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Still a Mystery

Well we got some good news and some bad.
Good news is the stuttering in the windowed mode is gone.
The bad is the flickering is still there.
Again only one channel. (CTV)
Only some programs and commercials.
Some commercials partially, not the whole commercial.

GRRRRRRRRRRRRRRRRRRRRRRRRRRR!
This is not only a recording problem but regular TV as well.
The same Video card and the only drivers this OS has seen.
Rolling back is NOT an option!
 

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...
"A possible reason for the change on your DVR is that we are sending variable bit rate instead of constant bit rate."...
wow, that's the first I've heard of an OTA broadcaster going VBR, I didn't think it was allowed, and I don't think most set top boxes can handle it.
 

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Thanks Burnaby Boy

"I was able to minimize the flickering by unchecking the "Enable Dynamic Contrast" in the catalyst drivers"

That took care of the flickering for me, thanks for the tip.:)

Thanks to all for the help as well.
 
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