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  1. Is there a frame size calculator for Mac that gives an optimal resolution to use when the video length, target size, audio bitrate, etc are input?

    I'm looking for something just like this: http://www.videohelp.com/tools/Aspect_2
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  2. Member
    Join Date: Jun 2003
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    How about just using ffmpegX or MPEG Streamclip? They will tell you the resulting size (MB) of the file when the other info is set.
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  3. I don't a program to tell me the file size. I have a preset value based on the media I plan to use in mind. What I'm looking for is optimal resolution dimensions based on file size (and hence video bitrate based on video duration) and audio bitrate I plan on using.
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  4. Member gadgetguy's Avatar
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    So you're looking for something to tell you information like this website? Click Here
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  5. Member edDV's Avatar
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    Originally Posted by headless chicken
    I don't a program to tell me the file size. I have a preset value based on the media I plan to use in mind. What I'm looking for is optimal resolution dimensions based on file size (and hence video bitrate based on video duration) and audio bitrate I plan on using.
    Resolution and bitrate are separate issues. Picture quality depends on the optimal combination of resolution and bitrate. You can have higher resolution with crap quality or lower resolution at higher quality for a given bit rate.

    DVD and other media fix resolution (e.g. 720x480 or 352x480) so the variable to play with is bitrate. Bitrate divides into constant or variable.

    If you don't care about DVD standard, you can use whatever resolution you want.
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  6. Originally Posted by edDV

    If you don't care about DVD standard, you can use whatever resolution you want.
    I'm looking for the best possible resolution for a 700MB file. D-Vision has a setting that calculates a resolution for you based on the file size/video bitrate and movie length, but I'm not sure if that's an optimal setting. It seems to be on the small side. I know larger resolutions at lower bitrates will lead to excessive macroblocking and other undesirable image artifacts.
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    Use ffmpegX, plug in the values you know, and click the "Best" button. This will provide you with the size of the resulting file. Reduce the frame size until clicking the "Best" button gives you your 700MB file size.
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  8. Member gadgetguy's Avatar
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    The filesize has almost nothing to do with what screen resolution you should use. The only concern for resolution is bitrate and codec. In general, a lower resolution allows for lower bitrates for any given codec. But some codecs give better results than others at any given bitrate. Using 700MB as the given information to determine a resolution is impossible without knowing the duration so you can calculate the bitrate.
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  9. Originally Posted by rumplestiltskin
    Use ffmpegX, plug in the values you know, and click the "Best" button. This will provide you with the size of the resulting file. Reduce the frame size until clicking the "Best" button gives you your 700MB file size.
    Thanks, I'll try this method. I usually steer clear of ffmpegx because I'll either receive several errors before or during encoding which begins the process to an abrupt halt, or the predicted file sizes are way off.
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  10. Member edDV's Avatar
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    Bit rate and file size are directly related. Both are independent of frame size.

    If any "calculator" is relating the two for a given codec, it is using a subjective relationship.
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  11. Originally Posted by headless chicken View Post
    I'm looking for the best possible resolution for a 700MB file. D-Vision has a setting that calculates a resolution for you based on the file size/video bitrate and movie length, but I'm not sure if that's an optimal setting.
    A program can't accurately determine that unless it examines the video and tests it for compressibility with the codec you plan to use. Some videos compress much more easily than others. Look at the three videos in this post:

    http://forum.videohelp.com/threads/295672-A-problem-for-video-experts?p=1811057&viewfu...=1#post1811057

    The one with the lowest bitrate (the smallest file) looks best.
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