I suppose this could be any one of the several issues that has been discussed here time and again regarding news tickers. I'd say the news ticker problem is generally just an interlacing/deinterlacing issue. TV is interlaced, 60 fields per second. You might as well think of it as 60 frames per second though, because more or less that's what it really is. Each field only makes up half of the frame, because each field is either the odd lines or the even lines. But you have to remember, each field really is a seperate moment in time. It is not two halves of the same picture. It is two seperate pictures, that only contain 1/2 the resolution you think they do. This is why news tickers look funky after you deinterlace the picture, because you're combining two seperate moments in time into one picture. This is also why sports seems jerky, you're taking a 60fps stream of data and crunching it down into a 30fps stream of data. If you're watching the recorded mpeg, and not a showsqueeze copy that's been deinterlaced, you can actually watch it without deinterlacing provided you use overlay rather than the 3D renderer. And if you do so the picture will look every bit as good as the actual TV picture does, because you're not ruining it by deinterlacing it. Of course, you also have to match your video card's output to the actual video signal, which means maxing out overscan and using 640x480 so that your 480 line signal is matching up with your 480 line picture. This works insanely well with my geforce3 card, using TVTool to overscan properly. This also works with the gffx5200 cards I've setup for other people, with the overscan setting in the drivers maxed out as far as it will go, and the deflicker setting cranked all the way down to the bottom, and then moving it up exactly one notch with the cursor key. Probably works just fine with newer geforce cards too, but I haven't tried it. <fanboy>And I'd never touch an ATI card. </fanboy>
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Originally Posted by grandpaken
How do you tell the actual frame rate we're capturing at? Is the jerkiness of scrolling news banners due to dropped frames or delayed frames...meaning if you're getting 30 fps but they come in spurts of 5 frames then a slight delay then the next 5 frames how can we measure it? Are there any free tools to test the frame rate in BTV?
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