For a long while, I have been running my box using the kerneldeint,denoise3d filter options to remove interlacing artefacts. This looked quite good on my monitor while I was setting up my myth box, but now the box is in the lounge connected to my TV, so what looks good on a progressive scan monitor is no longer important. Football (Aussie Rules) season has just started here, and it wasnt until I started looking at sport that I realised how bad an idea de-interlacing is when using an interlaced display (I use the svideo out on my Geforce2 MX 400). (I also receive DVB so the input video quality is excellent if i can just get the playback working right) Fast motion is noticably choppy watching thru the myth box compared to watching normal telly.

This is of course because the deinterlaced video is only updating at 25 FPS (I live in PAL land). So I started investigating what I would need to get something better. There is a lot of conflicting information out there but I think I learnt that the geforce4 and later do proper interlaced outputs and support tv out resolutions matching broadcast resolutions (instead of just 800x600 and 640x480 which dont match the aussie dvb standard of 720x576).

I then read an excellent page on deinterlacing which talked about the bob method (among others). Bob is where you display one field for 1/50 sec and the next field in the next 1/50 of a sec to complete the frame. This would look flickery on a progressive display (like a monitor) but it is just the shot for displaying to a tv. Using the bob 2x deinterlace method, when I watch footy on myth box, the motion looks the same as normal telly.

This is why (I think) : When the svideo is outputting the first field, myth displays the first field full screen and when the svideo is outputting the second field, myth shows the second field full screen, resulting in (almost) the correct fields being presented to the telly and presto nice smooth motion . I say almost the correct fields because the PAL svideo tvout has to produce 576 lines from the 800x600 xwindow resolution, and myth displays the 720x576 source video at 800x600 resolution on the screen so the video is scaled twice resulting in some loss of resolution.

But in summary, I am much happier with the output to TV using bob.

So what you're saying is "bob is your uncle"?

BTW - Bob is my uncle (or at least one of them), and let me tell you, he's a character of the first water...

What settings do you recommend for LCD monitor display?

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Not sure about LCD. Probably not bob (although the slow refresh rate of an LCD may make bob viable too)

LCD's don't have a slow refresh rate per say (they're often at the same frequency as a tube/crt) but they have a slower pixel fill rate..

nothing can really compensate for motion bluring because of the slow pixel rate.

Yeah what byronm said. I was trying to say that the slow pixel fill rate may reduce some of the flicker that is evident when using bob on a monitor.

would I be able to use the bob filter for NTSC. Could you expect the same benefit?

It seems to make my NTSC playback look better...

Can you post the link?
Thanks

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My guess is that Greg is talking about this:

http://www.100fps.com/

I could not get this BOB to work, and I tried both 720x576, and 720x576i (but don't use interlace, the tv-out-chip will do that for you) in XF86Config. The result would only come out as a horrible ghosted picture whenever there was movement. To work around it, I too used kerneldeint to get a "progressive" 25fps image, which looked fine on ordinary shows but stuttering on fast movement like sport.

The problem was simple: nvidias flicker-filter!

I ran "nvidia-settings" on my tv and reduced the flicker-filter from 128 to 1 (0 seems to be buggy). Everything became sharper, and bob began to work. It is now fluid and next to impossible to tell the difference between real TV and myth-TV.

The odd and even field information is now truly separated on screen and not blurred together to reduce flicker. Works well at 800x600 too since the current field is scaled to fit the screen.

With my old box (Nforce2 IGP aka MX4 graphics) the MythTV GUI fluttered like a flag in the wind when I turned this down much below 90. It was enough to make my head and stomach hurt in short order... I'll have to try it again with the new card (FX5200) which seems much less sensitive to it...

Actually I am running NF2-integrated... but my TV is 100Hz

Yeah, the new box is better but there's still no way that pushing it down to 0 is going to pas the *URP!* test. Window borders shudder like a dog trying to pass a peach pit at anything below 32, although 63 looks pretty stable...

I feel left out. I have NO idea what this "flicker filter" is. My nvidia-settings does not show a control with that label. Perhaps it's because I'm using the VGA out connector?

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