Anything Wrong With This WTV File?

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CyberSimian

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Anything Wrong With This WTV File?

#1

Post by CyberSimian » Wed Aug 01, 2012 11:34 am

I have an annoying problem with reception of high-definition channels (DVB-T2) on my system, and I am trying to narrow-down the possible causes. Strangely, the standard-definition channels do not exhibit this problem. If you satisfy the following conditions:

(1) Live in a country that has 50Hz mains frequency (== 50Hz TV frame rate),
(2) Use Windows 7 Media Center,
(3) Have a broadband connection,
(4) Have 5 minutes to spare,

may I ask you to download the WTV file specified below, view it on your system, and let me know whether you think that there is anything wrong with it? If you notice the same problem that I have noticed, it indicates that the problem is present in the WTV file, and hence my problem resides in the record chain (from tuner to disk; a problem with the tuner card, perhaps). On the other hand, if you do not notice any problem, it indicates that my problem resides in the replay chain (from disk to screen; a problem with the graphics card, perhaps). This is the WTV file; it is a 14 second clip, and is circa 11MB in size:

http://www.xenscape.com/anon/olympic_archery.wtv

So as not to prejudice your assessment, I will not in this post specify the defect that I have noticed. Many thanks.

-- from CyberSimian in the UK

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holidayboy

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#2

Post by holidayboy » Wed Aug 01, 2012 12:31 pm

I'll have a squint at it later :)
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#3

Post by bobbob » Wed Aug 01, 2012 3:42 pm

looks fine to me, don't see anything wrong

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holidayboy

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#4

Post by holidayboy » Wed Aug 01, 2012 3:55 pm

I see a weird flicker (I counted 5). It almost looks like the 29/59 USA thingy?

It happens in MC, whether in full screen or windowed mode.

In WMP, I see very small glitches at the point of the flickers in MC, but it's much less visible - just a small flicker in the on screen score graphics graphics.

I just did a quick test recording on 304 and see the same results, I see it when just watching Live TV on 304 also, it seems to only happen for me when the score graphics are on screen.

I've only tested two machines so far (both GT430/GT440 GPU). Maybe Intel / ATI will give different results?
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#5

Post by bobbob » Wed Aug 01, 2012 4:08 pm

intel here

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CyberSimian

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#6

Post by CyberSimian » Wed Aug 01, 2012 10:49 pm

holidayboy wrote:I see a weird flicker (I counted 5).
Yes, that is exactly what I see.
holidayboy wrote:I just did a quick test recording on 304 and see the same results, I see it when just watching Live TV on 304 also, it seems to only happen for me when the score graphics are on screen.
When I first noticed this problem, I checked all 5 high-definition channels. They all seemed to show the problem, although the severity seems to differ from day to day, and from channel to channel. I found that a good programme to check was "Deal or No Deal", which has copious amounts of the wonderful Noel "Tidybeard" Edmonds silhouetted against the barely-illuminated audience. The flashing is much more noticeable when there are large dark areas on the screen.

I see from your HTPC specs that you have a TBS 6280 tuner; I am using a TBS 6284 tuner. That may (or may not) be significant.

There is one other datum that I will recount, but which I do not know how to interpret. TBS provide their own application for watching and recording TV, called TBSviewer (actually a modified version of DVBviewer). So I installed that and tried it on live TV. I was surprised to find that it does not exhibit the flashing problem. I think that I set TBSviewer to use the Media Center codecs, so that ought to be common (but TBSviewer is so arcane that it is difficult to be certain of anything!). TBSviewer records high-definition TV to a TS file (not a WTV file), so I don' t think that it is possible to view the "olympic_archery.wtv" file in TBSviewer (but I will try this tomorrow, to check).
holidayboy wrote:I've only tested two machines so far (both GT430/GT440 GPU). Maybe Intel / ATI will give different results?
My other specs are: Dell motherboard, Intel Q6600 processor, Nvidia 8400GS graphics card. So our systems are similar in the significant aspects (TBS tuners, Nvidia graphics). It would be useful to have more respondents (I note that BobBob did not notice any defect).

-- from CyberSimian in the UK

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#7

Post by CyberSimian » Wed Aug 01, 2012 10:58 pm

bobbob wrote:looks fine to me, don't see anything wrong
bobbob wrote:intel here
Can you give us more details of your hardware? Is it an Intel motherboard/chipset with integrated Intel graphics, or are you using a separate graphics card? If the latter, is it Nvidia or ATI?

I remember from our previous discussion about refresh rates that you did not notice any difference between 50Hz and 60Hz. I wonder if your TV is doing some clever processing that results in the flashing problem not being visible?

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CyberSimian

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#8

Post by CyberSimian » Thu Aug 02, 2012 9:00 am

CyberSimian wrote:TBSviewer records high-definition TV to a TS file (not a WTV file), so I don' t think that it is possible to view the "olympic_archery.wtv" file in TBSviewer (but I will try this tomorrow, to check).
On neither of the "recordings list" panels does TBSviewer list WTV files, and I could not find anywhere to configure the file types that it would show, so I think that TBSviewer does not support the WTV file type.

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#9

Post by mark1234 » Thu Aug 02, 2012 9:04 am

CyberSimian wrote:TBSviewer does not support the WTV file type.
Don't worry, nothing does.

I was at the cricket last night watching Notts lose, but will try this file for you tonight. I have ATI graphics in my desktops.
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#10

Post by bobbob » Thu Aug 02, 2012 9:15 am

yes integrated intel graphics on a gigabyte motherboard. this one http://www.gigabyte.com/products/produc ... id=3772#ov i don't think its that special a tv 3 or 4 years old now. its a samsung and i'm just using the PC mode 1920 @ 60Hz

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#11

Post by bobbob » Thu Aug 02, 2012 9:18 am

also this weekend i am planning to replace my 4 hauppauge dvbs2 tuners with the TBS one, 6984 is it? so my findings from that may inform a little

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#12

Post by mbasker » Thu Aug 02, 2012 9:30 am

Intel HD3000 here, looks fine to me.

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CyberSimian

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#13

Post by CyberSimian » Thu Aug 02, 2012 10:33 am

holidayboy wrote:I see a weird flicker (I counted 5). It almost looks like the 29/59 USA thingy?
I had another think about this, and looked at this post from Newfiend:

http://www.thegreenbutton.tv/forums/vie ... 1a7#p21588

In the last paragraph he states that using version 304.79 of the Nvidia drivers (a beta version) cures the problem with the flickering in his test file. When I recorded "olympic_archery", I was using the most-recent WHQL-certified drivers, namely 301.42. So I downloaded and installed version 304.79, and it seems to have fixed the problem! There is no flickering on live TV, and my "olympic_archery" test file replays without flickering too! It needs more extensive TV viewing to be 100% sure, but so far it is looking good.

This problem looks to be a quirk of certain versions of the Nvidia drivers. I suggest installing 304.79 and seeing if it solves the problem for you. This also explains why those using Intel integrated graphics (bobbob and mbasker) do not encounter the problem.

My thanks to all those who contributed -- it lead to the solution. :thumbup:

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#14

Post by holidayboy » Fri Aug 03, 2012 1:44 pm

:)
Rob.

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