why is there a delay between sound and image?

Discussion in 'iPod touch' started by yael8, Nov 9, 2008.

  1. yael8

    yael8 New Member

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    i put a few movies on my ipod touch and in all of theme the sound comes after or before the image!!!
    why is that , and how can i fix it?
  2. Teslanaut

    Teslanaut Well-Known Member

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    My guess, you encoded/convert it improperly or used a shatty app to do so. Or you got it from a source that as I stated. My advice? Redo it. Check my sig for details.
  3. Meikura

    Meikura Super Moderator Staff Member

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    Try re-encoding the file and making sure the audio is synced to the video?
    Use a higher quality program?
  4. simonrichards150

    simonrichards150 New Member

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    If the sync is off and the video stutters too you have encoded with a bitrate or resolution that is too high.
  5. Abcmsaj

    Abcmsaj Retired Moderator

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    Light travels faster than sound.

    So if I stand at one end of a football pitch, with you on the other, and clap my hands, you'd find that you saw me do it BEFORE you heard the clap.
  6. Teslanaut

    Teslanaut Well-Known Member

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    Um... A Clap does not produce visible light. Your theory is null. Better to say, if I turned a flash light on, would you see the light first, or hear it turn on first.
  7. Abcmsaj

    Abcmsaj Retired Moderator

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    The distance you'd need to prove that light travels faster than sound would mean I wouldn't be able to hear the flashlight being turned on unless you had 17 megaphones consecutively on top of each other.

    A clap produces a moving image which is light being reflected into your eyes.
  8. simonrichards150

    simonrichards150 New Member

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    For one thing, you wouldn't hear a torch turn on across a field.

    And as you clearly don't know how light or vision works, I will gladly educate you.

    Light is constantly rebounding from objects, at different wavelengths, and in all directions. Meaning that your hands, while not producing light themselves, are effectively emitting the light rebounding from the actual light source, whether it is the sun, or a lightbulb, etc. So then this light that has rebounded from the hands travels at light speed into your eyes, and you see it before you hear the clap.
  9. Teslanaut

    Teslanaut Well-Known Member

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    How about in a Dark room? With no light then? If you were in a football field distance, depending on how hard you clap, the sound might not have the energy to travel the length of the football field.
  10. simonrichards150

    simonrichards150 New Member

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    How about a field, the actual subject of conversation?

    Why would someone try to demonstrate this in a dark room?

    1. It would be too small
    2. It would be dark...duh

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