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Video Data Rate

  1. Aug 25, 2006 #1
    Hey,

    Is there a way to alter the data rate of a avi video.


    The problem is when i watch a video on my tv it has a slight lag to it, some videos do and some dont. i compared all the info of the videos and the ones that laged had a video data rate of 93kb/s.

    thanks
     
  2. jcsd
  3. Aug 25, 2006 #2

    chroot

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    You can use video editing software like Adobe Premiere to re-encode ("transcode") a video file from one data rate to another.

    However, I don't think your "lag" problem has anything to do the data rate of the video -- it is probably just a poorly-made video in the first place. 93 kbps is actually an incredibly low data rate for video.

    Note that increasing the data rate of a poor movie isn't going to make it any better -- that would require the creation of new information, which the computer cannot magically do.

    - Waren
     
  4. Aug 26, 2006 #3

    rcgldr

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    Where did you find a video source that had a 93kbps rate? As mentioned its very low. For 640x480 videos I use about 2000kbs just for the video, which may bit of overkill, but file sizes are reasonable for 1 to 10 minute videos. DVD's range about 3000kbs to 9800kbs. HDTV (1080i) is 19.25mbps. BluRay DVD's (1080p) are even faster, 36mbps (1x) and 72mbps (2x), they need 54mpbs (1.5x) to get full quality transfer.
     
  5. Aug 26, 2006 #4

    mezarashi

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    Video lag has absolutely nothing to do with data rate.

    Video "lag" usually happens when either your CPU cannot decode the video fast enough, you have installed incorrect codecs or splitters, or there is a problem with the video's frame rate.

    How are you playing your videos on TV? Is it directly connected to your computer? If so, are you saying that this lag does not exist on your computer screen?
     
  6. Aug 26, 2006 #5
    Well i have a D-link media connecter thing (some bull**** name) where it will play movies from my computer wirelessly.

    ive downloaded a bunch of movies and most of them run great, but some have a little lag, when i watch them on my computer they are fine but not on my tv.

    if u want any screen shots of n e thing that will help let me know.


    Thanks!
     
  7. Aug 27, 2006 #6

    mezarashi

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    In that case, the lag can be caused by the data rate. It could be that the data rate at some scenes are too high for the wireless connection.

    I'd like to bring up two points for your own information however:
    - It is very common for video to look okay on TV and "laggy" on the computer, due to a bad deinterlacing scheme. The computer uses a progressive display while TVs are interlaced. DVDs come interlaced.

    - MOST codecs encode using variable bit rate. This includes MPEG-2 (default DVD codec) and MPEG-4 (default Blu-ray/HD-DVD codec). This means that the data rate is not constant. You cannot simply say this video is 93kbit/s. The bit rate changes depending on how much action there is in that particular scene.
     
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