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  1. Hi, I have some large .AVI's of a show. I want to reduce the size w/o losing much quality. This will be stored on hard drive so I was wondering if XVID/DiVX is still the preferred codec or are newer codecs like MP4/H264 or whatever are better for what I'm trying to do?

    The AVI files are 342mb each with a runtime of 24 minutes and 22 seconds.

    It's 25fps and a real life show, not a cartoon (if that matters, i dunno).

    Resolution is 640x480, audio is encoded with Mp3 at 128kbps (48000hz).

    I opened the files in VirtualDub and viewed the File Information, and it says it has 1835kbps data rate for Video so I'm assuming that's the bitrate.

    20 episodes:
    342mb
    24:22 minutes (real-life show, not cartoon)
    25fps
    640x480 res
    1835kbps bitrate?
    48000Hz 128kbps

    Also, I need to mass convert them/run it in batch mode. I'd like to get the file sizes down to around 180-200mb. Tthe quality of these video files are already noisy/blocky...I've tried using filters in VirtualDub and it helps, but it makes the whole encoding process significantly slower (5fps encoding).

    What encoder and codec would you suggest for reducing the size of these files and storing them on hard drive?

    Also, could you please include the optimal settings I should use for the codec (for instance, Xvid, what should I set the quantitizer/bitrate or whatever to).

    Thanks a lot guys.
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  2. Member mats.hogberg's Avatar
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    I'm afraid, halve the size, halve the quality. Seems like it's already some rather efficient codec as it is, so further shrinking will take its toll of quality.

    /Mats
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  3. Originally Posted by mats.hogberg
    I'm afraid, halve the size, halve the quality. Seems like it's already some rather efficient codec as it is, so further shrinking will take its toll of quality.

    /Mats
    Really? How are some movies good quality and only 700mb? Why does a 24minute episode have to be half the size of a 1-2 hour movie (700mb)?

    Also, the quality of these videos aren't great to begin with. They look like vhs transfers, and they have some noise.

    Thanks for the quick reply.
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  4. Always Watching guns1inger's Avatar
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    Most movies that are 700mb aren't 640 x 480. They are widescreen, with a width of 600 or less, and a height in the 300's. That's a big saving right there. Those that do have higher resolutions look like crap.
    Read my blog here.
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  5. Originally Posted by guns1inger
    Most movies that are 700mb aren't 640 x 480. They are widescreen, with a width of 600 or less, and a height in the 300's. That's a big saving right there. Those that do have higher resolutions look like crap.
    I don't mind reducing resolution if needed as long as it's not too noticable.

    Edit:

    Also, I have another show that was already encoded (not by me).

    199mb
    24:24 minutes
    25fps (real life, not cartoon)
    720x544 res
    1007kbps bitrate?
    MP3 128kbps (48000hz)
    The above show is good quality and probably had a better source, but it has the same runtime and i think even greater resolution or at least equal to 640x480?

    Thanks.
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  6. If you really want the smallest file size, especially with noisy video, use an MPEG 4 part 10 codec like x.264.
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  7. Member mats.hogberg's Avatar
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    Originally Posted by chroniX
    They look like vhs transfers, and they have some noise.
    That's something that really eats bitrate. It's not an indication of that a lower bitrate will do nicely.

    /Mats
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  8. Originally Posted by mats.hogberg
    Originally Posted by chroniX
    They look like vhs transfers, and they have some noise.
    That's something that really eats bitrate. It's not an indication of that a lower bitrate will do nicely.

    /Mats
    Well, I might have been exaggerating on the VHS transfer part. I think these were just badly encoded or something. If you want, I could post a 10 second sample or something and maybe you could take a look at it?

    Thanks.
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  9. Member mats.hogberg's Avatar
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    What I'm trying to get across is: The worse the source (noise, flicker & cetera) the higher bitrate you need. So much is wasted on keeping up with random pixels changing between frames, there's not enough left to cater for the real changes.
    Also keep in mind that each reencoding takes some quality away, even if you go up in bitrate.

    /Mats
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