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?
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
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.
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.
I've stumbled upon this question, and then stumbled upon the following online service that solves the problem:
Very nice, no need to actually upload the file, the conversion is done locally.