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I have a 4 GB MP4 video file that I shot with the HD Flip Mino. How do I reduce it to no more than 1 GIG without losing too much quality?

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You can try using something such as ffmpeg or mencoder to reencode it with a lower bitrate, e.g.:

Calculate the bitrate you need by dividing 1 GB by the video length in seconds. So, for a video of length 16:40 (1000 seconds), use a bitrate of 1000000 bytes/sec:

ffmpeg -i input.mp4 -b 1000000 output.mp4

Additional options that might be worth considering is setting the Constant Rate Factor, which lowers the average bit rate, but retains better quality. Vary the CRF between around 18 and 24 — the lower, the higher the bitrate.

ffmpeg -i input.mp4 -vcodec libx264 -crf 20 output.mp4
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    1000k is better than 1000000 in "ffmpeg -i input.mp4 -b 1000000 output.mp4" – iwill May 7 '13 at 8:47
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    -b takes the bit rate not the byte rate. If the video must be 1GB and the length is 1000 (one thousand) seconds, then the desired bit rate is approximately 1e9/1000*8 = 8e6 (8,000,000) bits per second (bps). – Jason Jun 4 '14 at 16:12
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    getting....The encoder 'aac' is experimental but experimental codecs are not enabled, add '-strict -2' if you want to use it. – Narendra Singh Jul 10 '15 at 9:09
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    @Jason I am pretty sure you mean (1e9 * 8)/1000. In other word (the desired video size in byte * 8) / (length of the video in seconds). – Dante Oct 30 '16 at 4:48
  • @Dante, the order of operations makes your equations and mine calculate to the same number. Though I see that it may be a bit confusing to put the "*8" after the division. It still calculates to the correct result. Well... unless you're thinking about rounding errors and machine math... then it is possible they will calculate to a slightly different result. – Jason Oct 30 '16 at 13:56
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You can non-destructively edit the file to clip out portions you don't want (take 1m off the beginning, 30s off the middle, 4m off the end).

Other than that, you're going to have to re-encode the mp4 as a smaller file. Try Handbrake.

  • Decrease the resolution from the Mino's native 1280x720 to something smaller, just preserve the aspect ratio.
  • Decrease the bitrate from the Mino's 9.0Mbps average bitrate down to something smaller

In either case you're losing quality. Try fiddling with either option (or both) and compare the results. Pick whatever looks best and has the right filesize.

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    H.264 FTW! – bgw Jul 16 '09 at 1:08
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Use "HandBrake". Import the file. Select "High Profile" and then click on "Start". It can compress 100 MB file to 27 MB or more. (Input file must not be in a already compressed state). If you use Handbrake version 0.9.5 then there is a setting to input File Size you want to compress in. (Upper version of HB does not have this feature).

Sorenson Squeeze is another professional Level tool for this kind of job.

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I've stumbled upon this question, and then stumbled upon the following online service that solves the problem:

https://clipchamp.com/

Very nice, no need to actually upload the file, the conversion is done locally.

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