Simplify OBS .flv video conversion to .mp4

If you use OBS to make your desktop recordings on your Mac, you’ll notice it creates .flv files by default. But .flv files aren’t playable in QuickTime.

There are ways to change the settings to create .mp4 files, but there are really good reasons to use .flv.

A better approach is to record in .flv and convert to .mp4 afterward using ffmpeg and a little shell script to make the commands easier.

By: phsymyst

Why record in .flv?
The real reason is, chances are your videos are going to be long and .flv can create a usable file even if an error occurs 2 hours into your recording. Other formats will be unusable. You don’t want to lose all that awesome recorded gameplay, do you?

To convert your .flv files, you’ll need ffmpeg to do video format conversion.

Install ffmpeg and make it executable from anywhere
I have a complete tutorial to install ffmpeg and make it executable on your system.

If you haven’t done so, follow these steps to install ffmeg on your Mac.

run ffmpeg to convert from .flv to .mp4
The command to run ffmpeg to convert your OBS output is ugly, but it works well.
ffmpeg -i filename.flv -c copy -copyts filename.mp4

Having used it, I wanted something simpler, so I created a short script called convertmp4. This script run the command for me and create a .mp4 in same directory alongside the .flv file.

To use convermp4, I run …
convertmp4 /path/to/filename.flv

And I get a new .mp4 file, like, /path/to/filename.mp4.

install convertmp4
You can download convertmp4 here: convertmp4.

Extract the file and move it to your /usr/local/bin, as superuser, and make it executable.

sudo mv convertmp4 /usr/local/bin
sudo chmod +x /usr/local/bin/convertmp4

If you try running it, you should see something like this (where “$” is your command line prompt):
$ convertmp4
Illegal number of arguments
usage: convertmp4 infile.flv

That means it’s working.

The contents of the script are like this gist on GitHub:

Here is the link for the script Gist on GitHub,

More information:

Author: eric

Eric Holsinger is a software professional and photography enthusiast in Southern Maine.