How do I reduce the size of a huge MP4 video?

Question

I paid $59.95 for Vimeo Plus only to find that there is a 1 Gigabyte limit on video size.

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?

Answer 1

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.

Answer 2

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

Answer 3

I've done some more research on this and I think the best answer for a Windows user is to use a GUI around ffmpeg. The two best ones I have found so far are WinFF and Super.