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  1. Member
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    Jan 2009
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    Australia
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    Sorry posted in wrong section, I fixed it now


    The 720p HDTV I record is 50fps, and I would like to encode it at 25fps. At the moment I have been decimating by 2 in Virtualdub, but I have been told this is not correct for the dvb source as it has a "unique pattern change". I'll provide a link to the source, and my encoded version so people can see how its not quite right.

    http://www.savefile.com/files/1977027

    http://www.savefile.com/files/1977046

    I'm not sure what the usual procedure is for progressive video, as everything I've dealt with in the past was 1080i. Advice specific to Virtual dub would be preferred as I have experience with it, but any advice is appreciated!
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  2. Member
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    I can't download the source here at work, but if it's 50fps progressive and there's motion on every frame decimating the video to 25fps will look jerky.
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  3. I think what you did is fine if you want to cut the frame rate in half. But you should have provided a clip from the main body of the video. Intro's like that often have odd properties. Most of your clip sas 25 fps converted to 50 fps by duplicating frames. But there were several slow motion sequences (4 duplicate frames in a row), some true 50 fps material, and too much temporal filtering. I suspect it was originally 1080i25 and was converted to 720p50 by bobbing.
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  4. Originally Posted by jagabo
    I suspect it was originally 1080i25 and was converted to 720p50 by bobbing.
    Which, if true, means it can be reinterlaced easily enough, although maybe not using VDub exclusively.
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  5. I'm assuming he wants to make MPEG4 AVI files so he doesn't want interlaced frames.
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  6. Oh yeah, you're right. I didn't get the samples, but clicking on the link to the reencoded version I see it's an AVI (which I probably should have figured out anyway, since he's using VDub). Thanks for the correction. I don't see how he can do any better than selecting every other frame. Not if using only VDub, anyway.
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  7. Mod Neophyte Super Moderator redwudz's Avatar
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    maggas, in the future, ask a Mod to move your post, don't make a duplicate post. Duplicate removed.

    Moderator redwudz
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