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  1. Member
    Join Date: Sep 2006
    Location: Denmark
    I've got to deliver a video for a 3 projector setup and the specification I got was to compress a 2875 x 768 .mpg or .wmv og .avi file. With no more than 3000 kbps and a file size no more than 250 mb.

    With sorenson squeeze or FFMPEG I'm not able to hit those specifications. Either because mpg dosn't allow uneven sizes or avi in sorenson don't go beyond 1920 px width or that 2875 px is not divideable by 16 in FFMPEG.

    What to do?

    I tried to project a wmv file with the closest width dividable by 16 - 2880 - but it looks quite blurred..

    Now I'm on to do a 2880x768 .avi but FFMPEG calculate a bitrate of 12000 or so?!
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  2. I'm a MEGA Super Moderator Baldrick's Avatar
    Join Date: Aug 2000
    Location: Sweden
    One similar post is enough. http://forum.videohelp.com/topic370216.html

    edit: Or I guess this is a ffmpegx specific question. Unlocking.
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  3. Explorer Case's Avatar
    Join Date: Feb 2004
    Location: Middle Earth
    2880x768 has an aspect ratio of 3:75:1, which is quite unusual.
    A picture with much detail may need 6200 kbps or more for that resolution, even with the superb compression of H.264. I can't imagine doing it with only half that bitrate.

    I recently saw a show that had a screen on stage that must have been close to 5:1. It featured very fine details at times. I still wonder how they did that.
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  4. Member
    Join Date: Aug 2005
    Location: Palo Alto, California USA
    Originally Posted by pisosse
    What to do?

    I tried to project a wmv file with the closest width dividable by 16 - 2880 - but it looks quite blurred..

    Now I'm on to do a 2880x768 .avi but FFMPEG calculate a bitrate of 12000 or so?!

    That calculation is an indication of your problem -- you want both high quality AND low bitrate (as all of us do!). These two goals are incompatible, however, and you will have to accept the tradeoffs that necessarily occur. If the 3000bps bitrate is truly an absolute maximum spec, then the quality you get is what you get (and it will not be very good). If the quality is unacceptable, then the bitrate must be increased for any typical video.

    As Case implied, H.264 is your best bet, but even so, you will need to increase the bitrate.
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