vmix

Trims and concatenates multiple video files together, using ffmpeg and an easy to use config file. Tested on Windows so far only.

• Why I built this
• Background
• Prerequisites
• Installation and Usage
• .vmix Config File
• Requirements: ffmpeg

Why I built this

I have a lot of .mp4 and .mov files from a lot of devices: Android, iOS, GoPro, DJI Mavic, Osmo, etc stored on my hard drive. They take up a lot of space, and also contain a lot of un-usable footage.

I wanted a single utility that achieves the following:

• Transcodes video to h.264 on the command line w/o having to go into Premier
• At the same time, have the ability to cut clips out of files, and re-stitch them back together to form a single output.

This allows me to preserve the parts of videos that I like, and significantly reduce file size easily via configuration from the command line without having to touch Adobe Premier. I take this "first pass", and then put it into Adobe Premier for further editing if needed.

Background

Here is an example of an ffmpeg command that takes an input file, chops it up, and re-stitches the segments together, taken from

https://superuser.com/questions/1229945/ffmpeg-split-video-and-merge-back

ffmpeg -i DJI_0069.mp4 -filter_complex ^"^
[0:v]trim=0:10,setpts=PTS-STARTPTS[v0]; ^
[0:a]atrim=0:10,asetpts=PTS-STARTPTS[a0]; ^
[0:v]trim=15:20,setpts=PTS-STARTPTS[v1]; ^
[0:a]atrim=15:20,asetpts=PTS-STARTPTS[a1]; ^
[0:v]trim=25:30,setpts=PTS-STARTPTS[v2]; ^
[0:a]atrim=25:30,asetpts=PTS-STARTPTS[a2]; ^
[v0][a0][v1][a1][v2][a2] concat=n=3:v=1:a=1[outv][outa]^" ^
-map "[outv]" -map "[outa]" output.mp4

This is for splitting and concatenating multiple files

ffmpeg -i edv_g24_2.mp4 -i short-video.mp4 -filter_complex "\
[0:v]trim=0:10,setpts=PTS-STARTPTS[v0]; \
[0:a]atrim=0:10,asetpts=PTS-STARTPTS[a0]; \
[1:v]trim=0:5,setpts=PTS-STARTPTS[v1]; \
[1:a]atrim=0:5,asetpts=PTS-STARTPTS[v1]; \
[0:v]trim=15:30,setpts=PTS-STARTPTS[v2]; \
[0:a]atrim=15:30,asetpts=PTS-STARTPTS[a2]; \
[v0][a0][v1][a1][v2][a2]concat=n=3:v=1:a=1[outv][outa]" \
-map "[outv]" -map "[outa]" output.mp4

This utility simply generates the above syntax, from a simple configuration file format

Prerequisites

Make sure you install ffmpeg and exiftool:

• https://www.ffmpeg.org/download.html - executable "ffmpeg" should work from the command line.
• https://exiftool.org/ - executable "exiftool" should work from the command line. This is used to restore the EXIF created date of the media file upon conversion

Installation and Usage

$ npm install -g vid-mixer
$ cd /into-folder-with-mp4-files/

$ vmix --init
creates **.vmix** config file in the working folder
use text editor to edit file

$ vmix
Cuts and concatenates video files based on the .vmix config (see below)

.vmix Config File

Here is an example of the .vmix file used as a configuration, for chopping and re-stitching videos

:timecodes
1 ; DJI_0111.MP4 ; 0:00,0:00 ; 0:00,0:00 ; 0:00,0:00
1 ; DJI_0112.MP4 ; 0:00,0:00 ; 0:00,0:00 ; 0:00,0:00
// the "1" is a group key, which groups both files to a single output

2 ; DJI_0113.MP4 ; 0:00,0:00 ; 0:00,0:00 ; 0:00,0:00

:groupFilenames
1 ; My custom filename
2 ; [delete me to override with your own filename (including brackets)]

:timecodes

• The first column is a GROUP KEY. Videos w/ the same index will be combined to generate a single output file
• The second column is the input filename, relative to the current path
• The 3rd and subsequent columns are trim timeframes in minutes : seconds

:groupFilenames

• Set custom filename output for each group.

Requirements: ffmpeg

This package assumes you have access to ffmpeg from your commmand line.

Type ffmpeg -h from a terminal, and make sure it exists. Otherwise, follow instructions to install ffmpeg from google