Video Compression: FFMPEG

There are a number of ways you can compress a video file. Adobe, Apple, Black Magic, and pretty much every other media development company out there has a tool that enables you to deal with your footage. In truth, many of them are interfaces wrapped around a core set of coding tools called FFmpeg. This is largely specific to Mac, although it would be very similar for Linux systems, but not really worth it for Windows.

This is a very simple guide on how to install FFmpeg command line tools, and what commands might come in handy. If you're looking to do more complicated things like making custom gifs, processing audio from video, or programmatically processing data from video, you can find the documentation on those moves here

Installing FFmpeg

To start you off, you'll want to install these tools.

At this point, you have a fully functioning compression program installed on your computer. Below, you'll find a number of commands that will assist in processing video files into smaller, more mobile codecs.

Transcoding Large Files

If you're new to command line tools, it is good to note that path/to/input.ext will always mean the directory path to the video file you're looking to process. You can manually type this, if you know it, or you can drag the file into your Terminal window and it'll autofill.

It is also important to note that with FFmpeg commands, the path/to/input.ext is the path to the existing file, but path/to/output.ext is a path to the file you'll be creating and doesn't yet exist.

ffmpeg -i path/to/input.ext -crf 23 -pix_fmt yuv420p -c:v libx264 path/to/

The command above should work right off the bat, all you need to do is replace your path/to/in-and-outputs and you should end up with a file that plays nicely with Quicktime and is small enough to send over Slack or Google Drive easily.

Turning this into a readily accessible tool

It's a little bit cumbersome to constantly be typing out the path/to/your/file. This is coding, after all, we should be able to make this quite a bit easier. Below, you'll find just a little bit more code that will make it so you can simply write makeitsmall and drag your file over, and it'll work for you!

Start off by opening Terminal and enter:

cd ~/Development

This will move you into your Development directory, if you don't have one, you can just write cd ~

Next enter: mkdir makeItSmall

cd makeItSmall

nano makeitsmall This is going to move you into your new makeItSmall directory and open a new shell script named makeitsmall Next up, paste this:


NEW_PATH="$(dirname $1)/$(basename $1 | cut -d. -f1)"

ffmpeg -i $VIDEOFILE -crf 23 -pix_fmt yuv420p -c:v libx264 $NEW_PATH

Exit using Control + X and save your file. Next we need to make this file executable

chmod 755 makeitsmall

And finally, we need to add this to the $PATH, which is essentially the directory of files that the command line looks for when given a new command. Type:

export PATH=$PATH:./makeitsmall

Now, I know this was a lot of steps! But it's a small investment on a relatively powerful return!

Whenever you have a large video file now, all you need to do is type makeitsmall and drag your video file into Terminal, what it will spit out is a light, moveable file!

Breaking down the options(100% optional, what you need is likely above)

If you're looking to understand the code, it breaks down pretty simply into a number of tags.