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  1. When watching videos on my media player, how different keyframe setup would affect this experience?
    Not technically but in practical terms.
    Thanks in advance
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  2. Member
    Join Date
    Sep 2002
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    Georgetown, TX
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    I think when you hit Fast Forward or Rewind is when the keyframe setting kicks it. I'm a newbie, too, so please someone correct me if I'm wrong, but you know how when you FF or RR your player starts jumping from frame to frame real fast? It's jumping to the next keyframe.

    So, the higher your keyframe setting, the faster you will fast forward. You don't want to set it very high, though, because then it will be hard to FF or RR to a specific location. (i.e. you'd keep missing the part you wanted to skip to because the next keyframe isn't for another 30 seconds when you only want to jump, say, 10 secs.) Make sense?

    Like I said -- Somebody PLEASE correct my ignorance if I'm wrong. (It'd be nice to hear I'm right, too, if that's the case.) hehe

    -- Matt
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  3. Member
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    May 2001
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    United States
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    I am assuming that you are refering to "I" frames as your "keyframes". I frames are the least compressed of the I, P and B frames in a DVD GOP. Normal GOP structure is 3-4 or 3-5 (grouped in 3 four or five times). Or:

    IPBPBBPBBPBB
    IPBPBBPBBPBBPBB

    From a practical standpoint, there may be a slightly noticeable quality increase by really lowering the frames between your I frames, but at the cost of more required storage space. However, this increase is probably not noticeable to most people, so is not worth the storage space. I've not done any testing to verify this, so any experiments that you do, you need to keep us informed.
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  4. Guys, thanks for your reply.

    Cradix, for some reason my wmp doesn´t give fast forward or rewind. I just get drag-and-drop on it.
    In this light, could help me understand how the keyframes would afect that?

    SLK001, I'm capturing in MPEG, VCD or AVI. Not DVD. What's your opinion about what I mentioned above.
    Thanks
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  5. Member
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    Originally Posted by bfeitosa
    In this light, could help me understand how the keyframes would afect that?
    Thanks
    Well, after SLK001's post, I'm not so sure I really know what keyframes are, so no!

    Where is the option to change the "key frame" setting? I've glanced through Vdub & TMPGEnc without any luck. I vaguely remember seeing it in DivX last night, but I just got DivX last night and I've seen it before that.

    -- Matt
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